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Tidoms. A preon builds particles, a tidom is a preon. A tidom is a one dimension fixed LENGTH and discrete TIME, not two different things, one thing, a tidom. Neither exist without the other and both only in this form. The length can’t be subdivided. There is no half length unit, there is no half time unit. If you are at some "point" on the length, you are at all the points on the length. The length and time are Planck's length and Planck's time. This tidom is the L unit. Everything in this universe is built from these tidoms and only tidoms. Thus tidoms in different forms are time, energy, mass, momentum, particles and even think, as you do. Everything means the only thing. Tidoms built elementary particles, then elementary particles build systems of particles and we are at a proton and neutron and bigger, a factor of R (10**20) in length. The physics changes greatly between elementary particles and systems of particles. Tidoms have these properties. Tidoms only exist in a state of three. That is why we are in a 3 dimensional universe. They have one "point" in common, the reason for both is that Time must start, or change values. To do this, 3 tidoms are needed. Time is used up to start time each tick of a tidom. This is a very small amount, about 1/R**3 (10**-60) of the amount of time changed. The time used in the change of time starts "down" the tidom towards the other end, then moves at right angles having started the time change. At right angles can be any perpendicular direction. There must now be a tidom there, and again starts time in that tidom moving one unit down its length and then at right angles. And third, there must again be a tidom there where again it moves one unit starting the third tidom and then moving at right angles. This new "place" is the start of the first motion of time and can only happen with at least 3 dimensions and be a minimum energy. Just as important is the fact that the 3 tidoms are not starting at the same moment, but in order. 1,2,3. This holds the tidoms together and as a unit of 3. It also explains that the 3 tidoms are either a right handed (1,2,3) or left handed (1,3,2) system. The difference is that the particle is either matter or antimatter for every elementary particle. To summarize, (1) Tidoms are discrete length and time. You can not subdivide either, nor have one without the other. (2) They are always in groups of three and each group is a particle. Only particles exist in nature. (3) They have one "point" in common. (4) They are either matter or antimatter as they are either right or left handed systems. (5) They use up time on each tick and they tick at their own rate, or a single particle has three different times. Next; we need to know that there are 3 different lengths and times for tidoms, L for low frequency, H for high and E for extreme. The ratios in the lengths are a factor of R in each case. The factor in the ratios of time is also R, so that the ratio of length to time is C in all three cases. The difference between L in length and the width of the proton is also R. There are 10 tables of particles, (LLL) thru (EEE). Three of these tables exist but are very unstable and particles only existed for about 10**-35 of a second at the time of our BB. We will not deal with these; (LLE), (LHE). (LEE) now. These are tables with both an L and E tidom. The table (LLH) is the Fermion table, and (LHH) the Boson. The table (LLL) are space particles, Spocks. The table (HHH) contains the unit mass, Mu; (EEE) contains supermass, Sm; and (HHE) the first particle, Eu at the time of the BB. (HEE) is the unit force, all other forces are a fixed number of these combined. We start with the properties of charge and color. Our charge is different than we think of charge now. We think of the electromagnetic force now. The electro and magnetic forces are two different forces. But the magnet force is always caused by two bosons (magons) being emitted at the same time any chargon is emitted. These two magons are at right angles and in opposite directions. Thus we can’t tell the difference between this and what we think is happening as an electromagnetic particle. The results always look like the electromagnetic force. The charge property comes from the tidom being shifted 180 degrees. That is, that the one point in common is at the middle of a tidom rather than at the end. This is true for both L and H tidoms. Thus any tidom shifted will contribute 1/3 charge to any particle with a 180 degree shifted tidom. The H may be shifted by multiple 45%s and have the property of color (3). Remember a shift of 180 degrees or greater changes the particle from right handed to left or to anti matter. Tidoms are independent of each other, and any or all may be shifted with respect to the other two. Each tidom has a mass state, determined by the starting point of all three tidoms. Thus every particle has three mass states, a zero mass is an acceptable state. So that the amount of mass is determined by the mass in the previous state as we change from one state to the next. To summarize. (6) There are 3 different frequencies for tidoms, L,H and E. We only see the E tidom at the time of the BB. (7) Every particle has 3 tidoms so these can be arranged in 10 different configurations or 10 tables of particles. (8) The property of charge or color is a shift of the tidom with respect to the starting point. L only shifts to the midpoint or charge and that now is an antiparticle. H can shift multiple 45 degrees for color and has 3 colors, at 180 or more it shifts to anti particle, (180 is charge only). (9) There are always three mass states for each basic particle, one or more may be zero and these states depend on the shifts of the 3 tidoms. Here are the 12 states for Fermions. Let the notations for the shifts be 0 if no shift, 2 if a half shift for charge, 1 if the shift is 45,90 or 135 degrees for the three colors and 3 if both charge and one of the colors, these last two apply only to H. Thus the allowed particles are (000) meaning the (LLH) is; first L not shifted, 2nd the same and the H is non shifted either. Next are (001), (002), and (003) for the three other H conditions. Also (020), (021), (022) and (023) if the 2nd L is charged shifted. and last we have (220), (221), (222) and (223). Thus there are 12 possible lowest energy, mass independent state particles. We know that there are only 4 in the standard model; Neutrino, Electron and two Quarks, one each with plus and minus charge. All 4 have three different mass states for 12 all together. The neutrino is the state (000), the electron is (222), and the two quarks are (221) plus and (003) negative. The charge in these (2) cases causes a right left handed condition twice for (221) and three times for the (222) and one for (003), thus one is plus and the other negative. 8 of the 12 are ruled out because the H preon needs more time to start a system if the common point is not the end point since Time must start in two directions and if the system changes handedness. The H preon rules out Bosons for the same reason. For the space particles the states are (000), (002), (022) and (222). None of these are ruled out. Therefore there are 4 Spocks each with 3 mass states, or 12 space particles. We only see one, the (000). We will find the other 11, all with mass, (very much) in the center of a galaxy. They cause the Fermi Bubble and form a stable system because the force of gravity is balanced by the electro charge produced by these particles. The rule for which states exist and why is not clear. But we need at least 2 states for the (LLL). The Bosons have 20 states; (LHH) has two possible values for L and 10 for the two HHs. The Standard Model is not correct with respect to bosons. The 4 (LLH) states all have a different value for H, namely 0,1,2,3. The bosons never have 2 color shifted Hs. This is because the H preon requires more time to start if the H preon starts at any place other than the end. Knowing the exact bosons would really help. But I will go with this theory before anything else, so here they are. The ones that exist are; (000) the real photon, (001) gluon, (002) the spon, (222) virtual charge photon, (022) virtual magnetic photon, these will now be called the charon and magon. The state (HHH), (000) is the unit mass, (Mu) exactly the mass of the neutrino. (EEE) supermass (Sm), (HHE) first particle (Eu), and (HEE) Unit force (Fu) and currently thought of as the graviton. Let us start at the Big Bang and see these last particles. All particles are built from three tidoms. All tidoms have common properties, therefore all particles have these common properties. For the L Tidom some of these are: 1) They are the lowest frequency, that is time has the largest change in value from one tick to the next. 2) There are always three tidoms to every particle. 3) They all are at right angles to each other. 4) They have one point in common always. 5) An L tidom is always aligned in the direction of motion first. The space particle, "Spock", for space block is the only particle in this table. 6) All tidoms may carry mass, thus there are always exactly three mass states for any particle. At least one state, normally the most stable may be massless. Tidoms are a function of time and distance, understand that energy is a form of time and energy moving over a distance is momentum, then a tidom is momentum. There are 10**105 spocks per cubic meter. Space and the concept of a mathematical volume are two different things. A volume may have from none, no space to at least 10 time more space than volume. The space block, spock, normally sits in Zu. The spock is surrounded by Zu. But multiple spocks may overlap in space. In our universe, vibrating time, we only "see" the spocks. There is no distance between spocks. An example to help understand this is a photon moving thru space. The photon moves from spock to spock each and every time cycle of the L tidom. The distance traveled is the length of the tidom and the time necessary is one tick. That velocity is exactly C and this is why the value is C and everywhere C. The value is C if there is only one spock per cubic meter or 10 time 10**105 spocks per cubic meter. This difference in the density of spocks or space per unit volume is how space expands or contracts. Normally space is about 50% of the volume. The bosons called a "spon" is the "force" necessary for the movement of spocks in Zu. (see LHH). Spocks are created from the decay of mass. This occurs within a star and in general causes space to move out and away from a star in all directions rather evenly. Space, a spock does have two special properties. One, but still in common with all other particles is an interaction between any two particles. All particles have a life cycle. If they do not interact with another particle within their life cycle their energy returns to Zu. This is the same action as borrow energy. The reason the spock is so involved is that it is the only particle around most of the time for most of the interactions. Even two spocks must interact in this way. That is done by the "spon" boson. The second property is called an energy chain. A particle never sees the future, it only knows now and the past, whatever just happened. In the case of the spock, since all three tidoms are L, the past is a long time for particles and given that most of the time just two spocks are interacting they are extremely well in sync. A virtual particle passing thru space will leave every spock it passes thru in prefect timing such that a chain some R (10**20) spocks long is in complete sync. This is an energy chain. Real photons will not do this. Let us start with the movement of mass in a spock. Mass, like any other particle is a particle. The spock is R times larger in volume than a fermion, fermions are R times larger than boson and bosons are R times larger than the unit mass. R**3 (10**60) unit masses fit into a single spock, never more. For the unit mass to pass thru one spock it must pass thru every possible location in the spock. The spon is responsible for the movement of particles, including the unit mass from spock to spock and all move on the same and only one tick. Therefore, the minimum velocity a unit mass may have is one change of position in every tick of the spock, or the L tidom. If the mass does not move, and the two particles do not interact with still another particle, both will return to Zu. Since the number of movements is an integer, the change in velocity is one unit of momentum. The masses only change momentum by this unit. All forces are from, a form of a single unit forces.

We start with DEFINITIONS. Nothing; nothing is exactly that, nothing; no time, no distance, no space, no rate of change, no quantum flux, no probability, no negative energy, no anything. Nothing may be a point or infinite, but not a space because we would have jumped right over 1 and 2 dimensional nothings. Nothing can’t create anything. If nothing exists, nothing can’t then not exist. Nothing can not change with respect to anything. time; (small t), a one dimensional parameter used in math and physics that extends to infinity and beyond in both directions. time is continuous. Its value is determined by the difference between two time events. It has no rates of change with respect to any other variable. No rate of change of the rates and its rate is 1 with respect to itself at all times. It is not a particle and has no energy. time can’t have started or stopped or it would not be continuous at that point or the next. All other variables have 1st, 2nd, 3rd, etc. rates of change with respect to time. Point; points are considered to be continuous. Points may be different from each other or may be the same. Points in 0,1,2,3 or 4 dimensional space are all different. There are no points next to the one in a 0 dimensional space. And only two next to any in a 1 dimensional space. In a cube, we may add any number of line segments or planes, each full of points (1D, 2D), and the cube is still empty. But we can’t add one more 3 dimensional point. We may pour an infinite number of points into a cube and they all end up at the same point (all 3D). For points to fill the cube they NEED a line segment. That segment is the distance between any one point and any reference point. Without the 3 dimensional line segment with each point, we can’t fill the space. So points in any space, except zero, do not exist without a line segment. BOTH are needed. Space; space is undefined. It may be finite, infinite, here before timed started, start from nothing, curved, able to double, move matter or not, create matter with negative energy, limit speeds, full of universes, even multiple spaces, etc. etc. Space is completely undefined. These are not my definitions for nothing, time, point or space. They are what I assume other people will understand if I use these words. You may change them any way you like. I assume the first three "things" do not exist, and space has NO listed properties from above. Now my definitions. We will use a general rule to help us stay on track as we start. Nature is simple. If we must make a choice between options, we will choose the simplest and continue. Since I assume; nothing, time and points do not exist and space is a question, as defined above, what does exist ? If these have a property in common, that property must be wrong. One property is that they are all continuous. If length and time are not continuous, then all the math in the physics one now knows is wrong, some good approximations, but wrong. If nothing does not exist, what can the next "bigger" thing to nothing be ? Assume nothing can accumulate something; Time, which is not changing or unused Time. A nothing which can accumulate unused Time, the Time isn’t changing and the amount of that accumulation is zero, is pretty close to nothing. TIME(T) is only passing in terms of small t (time). We will call this nothing a Zero dimensional degree of freedom universe or Zu. A zero degree of freedom universe does not mean there is not a length, it means there are not lengths. Zu has a length, a discrete, single length and all points on that length are the same point. One can not have time without length, neither exist without the other. A place where unused Time accumulations and keeps getting bigger and bigger. In terms of places we already know, think of it as the place where borrow energy comes from and returns to and is always here. TIME (T) is discrete. Here are two examples to help understand discrete Time. One: consider a movie. Here each frame has stopped time. Nothing is in motion, yet the movie seems real. If we use a high speed camera, we can study things we would never see without one. Now think of a super high speed camera. Let each frame capture a photon. The photon is moving Planck’s length, 1.6x10**-35 m between each frame. The time between frames is Planck’s time, 5.4x10**-44 s. This is nature, this is how Time ticks and photons move when the photon stands still in each frame. If we could take frames 10 times faster, the photon will not move for 9 of them and then "jump" to the next frame. This is why C exist and is the value, C. C is not a maximum velocity; it is for real photons only. Two: assume time is continuous. Construct a small unit of time, a tenth of a nanosecond, (10**-10 sec.). Now fill the universe with zeros and place all behind the zero in the exponent. This is a "FLICK". What must happen in a flick ? Every particle must move "properly". To do that each particle must be paired with all others in the universe and each must "fit" all the laws of nature. That is a very little amount of time to do that and it must be done very many times per second in a flick. One may say nature does that. Take all the zeros in the exponent and copy them in place of the zero in the base, this is a "small flick". Now nature must figure out how each pair moves again, and if there are multiverses, how all those pairs move too. All that in LESS TIME AND MORE TIMES PER SECOND. One may still say nature can do that. Next step, double all the zeros. Inflation doubles space 100 times, we are only doubling zeros, much easier. Double 100 times, that is a "VERY SMALL FLICK”. The problem is much worse, and we haven't even started doubling zeros. If one assumes nature does not use time to figure out how a particle moves then one would know the outcome of the Big Bang before it even started. The end result of this logic is that particles do not see into the future, they ONLY KNOW NOW. Bye, bye Quantum Mechanics. The second mode of Time is used Time, a Tidom. A tidom is a preon which builds elementary particles. All elementary particles are built from three tidoms and only tidoms, even mass and space, all exist within Zu. Mass is a form of energy, energy is a form of time. A tidom is time, changing over a distance, momentum. Momentum is more fundamental than time or distance, one does not exist without the other. Think of time at point P=A and T=1, it then jumps, changes to P=B at T=2 and back again to P=A at T=3; this is a tidom. It is a Time cycle. The length (L) is the distance between A and B. The time passed is the difference between T=1 and 2 or 2 and 3. The Time did not move between A and B, and there are no values of Time between T=1 and 2 or 2 and 3. The length L is discrete, it is not subdivided. There are no values of x within L. The length is in 1 dimension and time is a property of that length. Nature is simple, tidoms are simple. A second look at a Tidom: If a POINT does not exist, what is the next "bigger" thing that does exist. This will build the universe and everything in it. It is a preon, that which builds all elementary particles. Start with a point, in math, (x,y,z,t) as used in Special Relativity. However, we see that If two references are moving the value of time (t) is determined from the dimension in motion, which implies that if x, the property, t for y, z and x are not independent of each other. So the point we will start with is (x,y,z) with times (tx,ty and tz), or three independent times. This isn’t hard, as later one may assume the three are just one time. Now we need something "bigger". If the value of x in a point is a single value, then to be bigger we need x to be a line segment, (Lx) with its own time (Tx). This is a Tidom, a time degree of freedom. The tidom is the line segment with its own time. Both the line segment and time are discrete, (L,T)x. For now, Planck's length and time. We CAN NOT have one without the other. We saw that points need a line segment. Time and Length are two different properties of the same thing, of a Tidom, both are ALWAYS together. We need to start again at 3 different places. When Time first started, because we need to know what was here before any Big Bang (BB). When Time started at this BB, because it will help to understand first particles. And what are the properties of a Tidom, because they build particles which then build systems of particles which we see. These 3 are related and thus necessary to each other, we will cover a little of each first. Hopefully ending with a follow up explanation later. Start with small t, time in both directions. At some time in the past there was no Time in Zu. There was a Zu. Now unused Time starts to accumulate. No Time is passing so this period of Time is zero, but not necessarily from t's point of view. And the amount of unused Time accumulated may be very different from the amount of time (t) that passes. On the far side of this start time; using t, only Time could have existed. This cycle of unused Time starting and ending with zero unused time could have repeated may times. But none of the cycles are infinite, because if one can’t get from here back an infinite time, then time from there CAN’T get here. There is a reason for Time starting, so that Time can stop. Remember if time is the only thing in this universe and you think, then time thinks. That's as much as I may say at this time about Time starting. We now have unused Time accumulating in Zu. The unused Time is one of two modes of Time, the other is used Time or vibrating Time, or Time that changes values. As unused Time accumulates, it reaches an amount which will change states to the other mode, used Time, or vibrating Time. This creates a particle in Zu. When all the accumulated Time changes modes, the unused accumulated amount is zero and the vibrating Time is now a particle in Zu. The first Big Bang was very small compared to ours. At some time later all the vibrating Time will stop vibrating and all that stopped Time is now unused Time in Zu again. It is still later, more unused Time is in Zu than at the time of the first Bang, because there is another period of unused Time accumulating. Some of the used Time was "lost" to make Time tick, but the total is more and we have a second bigger BB. The physics between the two Bangs is different. The reason is that we started with nothing, added the start of Time and the reason for doing that. If you have nothing, add Time, the only reason possibility is to stop time. To do that all vibrating Time must return as unused Time and in Zu. However that does not stop Time, it only keeps it from changing. To have no Time you need to use up both modes of Time completely. Since the first BB did not do this, the laws of physics change. The evolution of the laws is like any evolution. The laws optimize over some parameter, in this case, either or both R and C. The optimization is to have ALL amounts of Time used up at the same moment. Thus, we would see a universe that keep going longer and longer as we have BB after BB, each lasting longer. The reason for that is that as Time vibrates it uses itself up. That Time is not conserved, it's gone. Real Photons are a clear and easy example of this. Photons use up energy as their time passes, this is seen by their redshift. The Time in our universe is all from previous unused time that accumulated. All the time our universe existed, the current Time was accumulating in Zu. Thus, the particles must use more time than is accumulating for all of it to be used up at one moment. Now let’s jump to Tidoms and start physics.

This is brought to you by www.talkingorigins.org So forgive the copy and paste here. They simply put this more clearly and scientifically then i possibly could. So enjoy. This is part of what convinced me that evolution was indeed sound science 1. “Where is the missing link/ transitional fossils?” First of all, it should be noted that fossils are not easily found. They are rare, as general conditions do not always favor the formation of fossils. This being said, we actually have a HUGE number of transitional fossils and links between species. While it’s true that we won’t be able to find every single fossil for every single species that has ever existed, we have more than enough to accept the fossil record as extremely important evidence. An analogy would be this: ABCD_FGHIJK_MNO_QRST_VW_YZ. We have some blanks, but we can pretty much figure out which letters (or in evolution’s case, species containing certain traits) fit into these holes. Keep in mind that not having a perfectly complete fossil record is NOT evidence against evolution. It simply implies that there’s still room for improvement, and we still continue to fill in the blanks with new fossil finds. Here is a great reference with an enormous listing of different fossils and links: http://www.talkorigins.org/faqs/faq-transitional.htmland here’s another: http://darwiniana.org/transitionals.htmand ::gasp:: here’s ANOTHER: http://www.holysmoke.org/tran-icr.htm2. “My grandfather is not a monkey!"It’s a common misconception to think that we directly came from monkeys. In reality, we actually share a common ancestor with apes (kind of like a family tree that branches off). To defend the claim that we share a common ancestor with apes, we have many evidences (such as the fossil record), but we have recently discovered two newer, amazing pieces of evidence. The first is that our chromosome pair #2 is consistent with the fusion of two ape chromosomes, and the second is a series of perfect matches between our endogenous retroviruses. The latter essentially proves ape common ancestry beyond all reasonable doubt. You may not understand these two genetic terms, but these two videos do a very good job of explaining just how important these are for evolutionary theory: http://www.youtube.com/watch?v=8FGYzZOZxMw&feature=related and http://www.youtube.com/watch?v=TUxLR9hdorI3. “Evolution is *just* a theory!”Evolution is a scientific theory. It is labeled as such for two reasons. The first reason is that it has accumulated so much scientific evidence defending the claim, that it has gone from being an unjustified hypothesis to a justifiable theory. A “scientific theory” is not the same as a “guess” or “hypothesis” (or a regular “theory” in layman’s terms). It is the official scientific explanation for a huge set of facts and evidence. Secondly, it is called a scientific theory because, by definition, it is possible for it to be falsified. If a piece of evidence were to contradict evolutionary theory, the current theory would be dismissed and discarded. This has never, ever happened. Ever. This should show just how powerful this scientific theory really is. It should be noted that other scientific theories that are just as widely accepted in the scientific community include gravity, cell theory, plate tectonics, the big bang theory, and the atomic theory. These are all scientific theories. Yes, gravity is on par with evolution. Too many people think that a scientific theory could potentially be raised to a higher level (*if only there were enough evidence *). There is NO higher level. For instance, a scientific theory does not have the potential to become a scientific law, because they are completely separate things. A scientific law is not above a scientific theory. A law is a principle or guideline to keep in mind (such as the laws of thermodynamics), whereas a theory is the best current explanation for a set of facts. A scientific theory is the highest possible achievement of science. Evolution is not *JUST* a theory… it is TRIUMPHANTLY a theory (http://notjustatheory.com/)This site also gives very good explanations: http://wilstar.com/theories.htm4. “Evolution can’t be proven!”I redirect you to my third misconception; theories, by definition, can’t be proven due to the fact that they are hypothetically falsifiable. For instance, if I held an apple in mid-air, and let go of it… and it didn’t fall, but just floated there… then I would have just falsified the theory of gravity. Similarly, if a scientist found that, on a genetic level, humans have more in common with oak trees than monkeys, it would falsify our nested hierarchies and evolutionary chain. These things have never happened.5. “Evolution is wrong because the fossils indicate a young earth.”The young earth argument basically says that if the earth is 10,000 years old (or less), then evolution simply would not have had enough time to run its course (which is true). However, an old earth (billions of years old) is accepted due to radiometric dating (not just carbon dating) and is mathematically and scientifically sound. Many people who say, “well this organism was dated to be two million years old when in reality it was only fifty years old” don’t realize that certain isotopes can only accurately date certain eras (based on their half-lives). For instance, carbon dating is very accurate for things that have been around for the past 10,000 years, but not to date things millions of years old (and so scientists use other isotopes for the older stuff). Here’s a site about which isotopes are used to date back to which eras (and more general information about radiometric dating): http://www.asa3.org/aSA/resources/Wiens.html#page%2019We can also check these dates against other dating methods, which include varve counting, pollen analysis, ice core dating, tree ring dating (dendrochronology), coral dating, fluorine testing, thermoremanent magnetism, thermoluminescence, electron spin resonance, cosmic-ray exposure tests, and more. We have more than enough ways to date fossils AND eliminate any large inaccuracies. Whether a fossil is 37 million years old or 39 million years old is hardly something to lose sleep over. Most dating methods give ranges, anyway.6. “Evolution is wrong because fossils are consistent with a global flood.”This argument from ignorance actually amazes me. All fossils found in the same era are found in the same layer of earth. Older fossils are found in lower strata, while newer fossils are found closer to the surface. It’s as simple (and logical) as that. The only initially-puzzling special case is when we find older fossils on mountain tops… however, this is because of how those specific mountains were formed (two earth plates pushing against one another for millions of years caused the mountains to form; the earth used to be flatter way back in the day). For a global flood to be correct, ALL fossils from ALL species of living things would need to be found in the same layer of earth (whenever the global flood occurred); that means that you should be able to find a human’s skeleton next to a dinosaur’s. This has never been the case. Ever. Furthermore, here is a video that explains a logical alternative to the “global flood” myth, which is often created due to the Biblical flood story: http://www.youtube.com/watch?v=cq0dBFqJZc07. “What about Noah’s Ark?”This is similar to number six. This is also where it gets ugly, when people try to mix religion with science. You simply can’t do that. Religion is faith-based, whereas science is evidence-based. There is no proof that the Ark was real, or that there ever was a global flood. Since this is such a weak argument against evolution (there are actually many ways to disprove the global flood myth from a scientific standpoint, including the facts that the food/waste for/from every animal could not also fit onto the ark, plus carnivorous animals would eat the other animals, plus all of the plants on earth would die of drowning, plus all of the saltwater fish would have died due to the freshwater rain changing the ocean’s salinity, plus the fact that the animals would have had to carry all of the viruses and bacteria, plus apparently rabbits decided not to “screw like rabbits” for a whole year, plus the fossil record disproves it… but I digress), I’m just going to cut to the chase and post a video that shows one example of irrefutable scientific evidence (the bottlenecking of the cheetah) against the Noah’s Ark/global flood claim: http://www.youtube.com/watch?v=rIlWKp44T508. “I believe in Intelligent Design.”Quite frankly, you shouldn’t believe in Intelligent Design (the umbrella hypothesis that includes Creationism). That’s the problem right there. It is unfortunate for those who like the idea of ID, because not a single shred of evidence has been presented to defend this hypothesis. The foundation of ID is Irreducible Complexity, and every supposed “example” of this has been found out to not apply. Exactly what things ID and IC claim are explained in the following video. Here is an example of the main argument for IC (and it’s debunking), the Bacterial Flagellum: http://www.youtube.com/watch?v=K_HVrjKcvrUID doesn’t impress the scientific community (the people who matter when it comes to facts and evidence) because there is no logical reason to believe in it.9. “Evolution contradicts God’s existence… and… therefore, science is wrong."Besides being a clearly illogical argument, I’d like to say: Nope. It does not. Evolution (and science, in general) says NOTHING about the existence of God. Evolution and the rest of science are SECULARIST, not ATHEISTIC. It may disagree with the Creation story in the Bible’s Genesis chapter, but it does not, in any way, falsify or contradict the concept of a general deity. It is possible for God to exist with the intent of creating the universe in such a way that this scientific process of evolution could have run its course (I recommend looking up the very smart and *safe* religion of Deism). Therefore, God and evolution can both exist. Of course, it should be noted that possibility is very different than probability. Quite frankly, Christians should be relieved that science is incapable of disproving God, or else evolution would be proof that their deity can’t exist (based on Biblical claims)10. “There’s evidence for micro-evolution, but not macro-evolution.”This is actually just plain false, but allow me to first explain the terms. Many people choose only to note the tiny steps (a mutation here, a new function there) and thus believe that only micro-evolution occurs and not macro-evolution. Micro-evolution and macro-evolution are terms used by IDers to try to weasel their way around the truth of evolution. Micro-evolution is supposed to be changes within a species, while macro-evolution means changes that connect one species to another. In reality, scientists decide when enough small changes have been generated (usually through multiple generations) to label a new organism as a new species. Evolution is evolution, period. Skeptics need to take a step back and look at the bigger picture. We all know that micro-evolution is observable and testable. A very simple and common example of this is the fact that every few years we need brand new flu vaccines; viruses and bacteria often evolve rapidly and overcome our current treatments. You USUALLY won’t witness a macro-evolutionary step in your lifetime, because a macro-evolutionary step could take tens of thousands of years to occur. However, one macro-evolutionary step could be the same as a hundred micro-evolutionary steps, and a few of those we CAN see in our lifetime. Looking back on our fossil records, we see all of the tiny steps (through our transitional fossils) and then choose to label a certain group of them as a single macro-evolutionary step. Here’s an analogy:AARDVARK (original word)AASDVARK (one micro-mutation, changing one letter)AASDVARL (one micro-mutation, changing one letter)AASDBARL (one micro-mutation, changing one letter)AASEBARL (one micro-mutation, changing one letter)AASEBALL (one micro-mutation, changing one letter)BASEBALL (one micro-mutation, changing one letter; new word )To go from AARDVARK to BASEBALL, six micro-steps took place in between the two real words. However, the first six “words” could be labeled as A-species, while the last word could be labeled as a new B-species (based off of the first letter of each “word”). Therefore, A-species to B-species could be considered a macro-evolutionary step, while the little “in-between” steps are micro-evolutionary.Another very simple word analogy is this: Accepting micro-evolution but not macro-evolution is like accepting that seconds exist but not whole minutes.***It should be noted that macro-evolution HAS been observed. Unique polyploidy generations result in speciation (which is the same as macro-evolution) due to there being more than the expected two homologous sets of chromosomes. This occurs more frequently in plants than animals. Here’s a reference regarding examples of unique polyploidy types and hybridization (as well as other examples): http://www.talkorigins.org/faqs/faq-speciation.html#part5The REASON this is an example of macro-evolution is because there are certain unique and beneficial capabilities that polyploidy organisms have over organisms with only two homologous sets of chromosomes. This is why they are classified differently. However, we have found that sometimes the latter organisms can produce offspring that (through mutations) have the polyploidy characteristic. Therefore, we have witnessed macro-evolution.Allow me to give some examples and references to back up my claim (as it is ALWAYS important when discussing science):"Ultrafrequent establishment of poly- ploidy in the homosporous Pteridophy- ta appears to be necessary to create and maintain genetic variation in the face of the homozygotizing effects of habitual self-fertilization in the monoe- cious gametophytes of these plants."~http://www.sciencemag.org/cgi/content/abstract/153/3733/305"Somatic polyploidy, defined as genome multiplication, was found in all differentiated mammalian tissues. The highest level of such a polyploidy was found in the myocardium. This phenomenon was shown to be associated with changes in the pattern of gene expression. Hence, polyploidization may create cells with new physiology. ... Thus, we suppose that additional genomes may serve for cardiomyocyte protection from oxidative damage in the hearts."~http://www.tsitologiya.cytspb.rssi.ru/46_2/anatskaya_en.htmCheck out this abstract as well (I can’t copy/paste this one, sorry guys): http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.es.07.110176.001233?cookieSet=1&journalCode=ecolsys.1If anyone ever says that macro-evolution has never been observed, you can safely correct them.***11. “Evolution doesn’t explain how the very first living thing came about.”It’s not supposed to. Evolution is the study of how living organisms have changed throughout history. Evolutionary theory does NOT deal with how the first living organism came from non-life. This is a separate scientific field of study, know as Abiogenesis. Evolution and Abiogenesis do not rely on one another. Whether the first living organism came from self-replicating RNA or proteins or amino acids or Zeus or Thor or the Christian God does NOT affect the fact that we have substantial evidence for evolution. Abiogenesis contains hypotheses, but is currently not up to “scientific theory” status. However, it should be noted that we HAVE created life from non-life. We know that Abiogenesis is an absolute possibility (though we’re not 100% positive if this first experiment is the correct one, which is why it is not yet a scientific theory): http://www.dailygalaxy.com/my_weblog/2008/06/harvard-team-cr.html12. “You can’t prove that God simply didn’t set up everything to fool us!”This is true. God could have planted every single fossil correctly, decided (unimaginatively) that all living things should be connected genetically, and every other fact we have for evidence could have been a front for a designer. Most people believe in some sort of God; however, most of them do NOT believe in a deceitful one. Based on facts, evidence, observations, experiments, logic, and common sense, there is no reason to believe that evolution is incorrect, or a trick devised by a deceptive deity. Genetics can tell us who our mum is just like genetics can tell us who our grandparents are and (if we go back far enough, which doesn’t make it any less accurate) we can also find out other ancestors (species-wise). In the Creationist line of thinking (doubt EVERYTHING in light of obvious evidence), one couldn't even prove that you're related to your mum! Even when she was pregnant with you, the fact that you look like your mum and have her DNA and genetic make-up CLEARLY only says that God implanted an intelligently designed fetus inside of her to make you APPEAR to be related Come on now. This isn’t logical or scientific, and it shows that some people are simply grasping at straws.13. “All of the alternatives should be taught in the classroom anyway. Everyone has a right to speak their minds. Let the children decide for themselves. It’s only FAIR.”This obviously is not even an argument against evolution, but an argument to try and convince an audience that science is subjective. This argument, however, presents the dangerous fact that some people want unscientific hypotheses (or possibly even religion) taught in science class. This is terrible, and must be stopped at all costs. There is no scientific alternative to evolution. There is no controversy. Intelligent Design/Creationism does not impress the scientific community, because it is a religious belief system and it has no evidence behind it. Teaching science in schools is not about freedom of speech or ideas. It’s about teaching what we know is correct. In fact, there are many instances where education is simply NOT open for interpretation. Should a math teacher say, “If you WANT, you can believe that a triangle has four sides?” NO. Should an English teacher say, “If you WANT, you can say ‘I brang my lunch to school,’ instead of ‘brought’?” NO. Should parents say to small children, I want you to go to bed at nine o'clock and always do your homework... but it's up to YOU to make the final decision on those things ? NO. Using this faulty argument, we should also teach that since gravity is also *just a theory*, we should encourage children to jump off cliffs so that they can make their OWN decisions on whether or not to accept it as truth. Remember, evolution is on par with gravity (they’re both at the status of “scientific theory”… neither have ever been disproven, and both properly explain all of the facts). It's NOT up to the children to decide. It's up to the experts. It's up to the scientists and the teachers. Parents and other adults need to set a good example for children. Teaching ignorant alternatives is not healthy, and it will, quite frankly, screw up the next generation. The concept of fairness may seem appealing, but this extremely short video will explain how teaching ID (or other unscientific alternatives) in classrooms is anything BUT fair: http://www.youtube.com/watch?v=aO5us0qHcwc14. “A butterfly is a butterfly is a butterfly.”This is the argument that a butterfly will only give birth to a butterfly (or that a dog will never give birth to a “non-dog”). Popularized by Kent Hovind, this argument against evolution actually defies the very definitions of evolution, speciation, and macro-evolution. I will use the butterfly scenario. An animal is considered a butterfly if it falls into Kingdom Animalia + Phylum Arthropoda + Class Insecta + Order Lepidoptera + any number of Families ( http://en.wikipedia.org/wiki/Butterfly ).This being said, there are still smaller classifications (Genus and Species), ALL of which are still considered butterflies . This means that a butterfly parent could hypothetically even have an offspring in a different GENUS (not just Species) and it STILL wouldn't fall under the ridiculous ID goalpost-moving fallacy (http://en.wikipedia.org/wiki/Moving_the_goalpost ).You might as well move the goalposts all the way back from the get-go and say evolution hasn't occurred because animals only give birth to animals .15. "Evolution violates the second law of thermodynamics.""This shows more a misconception about thermodynamics than about evolution. The second law of thermodynamics says, No process is possible in which the sole result is the transfer of energy from a cooler to a hotter body. [Atkins, 1984, The Second Law, pg. 25] Now you may be scratching your head wondering what this has to do with evolution. The confusion arises when the second law is phrased in another equivalent way, The entropy of a closed system cannot decrease. Entropy is an indication of unusable energy and often (but not always ) corresponds to intuitive notions of disorder or randomness. Creationists thus misinterpret the second law to say that things invariably progress from order to disorder. However, they neglect the fact that life is not a closed system. The sun provides more than enough energy to drive things. If a mature tomato plant can have more usable energy than the seed it grew from, why should anyone expect that the next generation of tomatoes can't have more usable energy still? Creationists sometimes try to get around this by claiming that the information carried by living things lets them create order. However, not only is life irrelevant to the second law, but order from disorder is common in nonliving systems, too. Snowflakes, sand dunes, tornadoes, stalactites, graded river beds, and lightning are just a few examples of order coming from disorder in nature; none require an intelligent program to achieve that order. In any nontrivial system with lots of energy flowing through it, you are almost certain to find order arising somewhere in the system. If order from disorder is supposed to violate the second law of thermodynamics, why is it ubiquitous in nature?"~http://www.talkorigins.org/faqs/faq-misconceptions.html16. “Darwin recanted his belief in his own evolutionary theory when he was on his deathbed.”This is a misconception taken grossly out of context. The backstory here is that a woman named Elizabeth Cotton (also known as Lady Hope) visited Darwin when he was nearing the end of his life. The following is taken from a website that is famous for its ANTI-evolutionary and pro-Biblical literalist opinions:“Further, it is fascinating what Lady Hope’s story does not say. It does not say that Darwin renounced evolution. It merely says that Darwin speculated over the outcome of his ideas. He never backed away from evolution. Nor does the Lady Hope story say that Darwin actually became a Christian.”~http://www.answersingenesis.org/articles/2009/03/31/darwins-deathbed-conversion-legendAnd, of course, pro-evolution websites explain the same thing (such as http://www.talkorigins.org/indexcc/CG/CG001.html). Lady Hope actually visited Darwin months before he died, and she wasn’t even with him when he was on his deathbed. Most importantly, even if this whole fairy tale were true, it would not make evolutionary theory any less valid If Newton had renounced his scientific views on his deathbed, he wouldn’t have flown into the ceiling.17. “Mutations never provide *new* genetic information.”This is a very common misconception, and probably one of the funniest arguments ever; EVERY mutation technically provides new information.If a base pair is inserted, then that's the addition of new information.If a base pair is removed, then the resulting shift from the rest of the bases in the sequence causes new information.If base pairs are switched, then that's new information also.In every single mutation, new triples emerge. Therefore, there is always new information.Let's say we start with: ...-ATA-CGC-ATA-CGC-...Insertion of C between first T and second A: ...-ATC-ACG-CAT-ACG-C...Deletion of first G: ...-ATA-CCA-TAC-GC...Switching second A with first C: ...-ATC-AGC-ATA-CGC-...As you can see, regardless of what mutation occurs, new triples form. This means that new information is being processed. To say that no new information ever occurs due to mutations could not be more wrong; new information ALWAYS forms due to mutations.Finally, here is a huge reference defending the entire scientific theory of evolution: http://www.talkorigins.org/faqs/comdesc/Only 2% of scientists even consider Intelligent Design as a HYPOTHESIS (not even close to a scientific theory), which is about the same percentage of geologists who consider the possibility of a flat earth (check out the Flat Earth Society if you want a few good laughs). There will ALWAYS be a small group of people who refuse to accept facts that may go against personal belief. It's called denial. The other 98% of the scientific community recognize evolutionary theory (and, in the analogy, a round earth) as truth. If the experts accept evolution as the prominent, unifying biological theory, why should the less-educated disagree? It’s always good to be initially skeptical and ask questions (this is how science progesses), but it should be painfully obvious that scientific theories have already gone through rigorous processes (make sure you watched the short video at the end of misconception thirteen). There is an abundance of evidence for evolution; there is none against it (or for any alternative). There is no controversy. It’s vital that we silence the myths and correct the misconceptions. Personally, I’d like to stick twenty Creationists in a room with twenty tigers and show them that survival of the fittest really DOES work… but as for right now, I’ll stick to the Facebook debates.18. “Evolution is wrong because of the Piltdown Man, Haeckel’s Embryos, or any other famous scientific hoax!”Like other areas of science, evolutionary theory has had its fair share of greedy scientists who fabricate finds and make up data in poor attempts to gain a quick path to fame and fortune. However, it has always been the case that, through peer review, OTHER scientists have discovered the occasional forgery and refuted it. Science is, after all, self-checking. The rare fake does NOT discredit the hundreds of thousands of other genetic, geological, and biological facts that all agree with one another and validate evolutionary theory. Besides, there have been plenty of fake religious propaganda and forgeries as well (Paluxy tracks, Peter Popoff, Shroud of Turin, Kinderhook plates, etc.); you wouldn’t want us saying that your entire religion is false just because some religious fundamentalists fabricated “evidence” to further THEIR own agendas, now would you?

What's up with it? Is it true?

I saw this interesting question--what is the speed of dark-if it even has a speed?

Human evolution is the lengthy process of change by which people originated from apelike ancestors. Scientific evidence shows that the physical and behavioral traits shared by all people originated from apelike ancestors and evolved over a period of at least 5 million years. One of the earliest defining human traits, bipedalism -- the ability to walk on two legs -- evolved over 4 million years ago. Other important human characteristics -- such as a large and complex brain, the ability to make and use tools, and the capacity for language -- developed more recently. Many advanced traits -- including complex symbolic expression, art, and elaborate cultural diversity -- emerged mainly during the past 100,000 years. Humans are primates. Physical and genetic similarities show that the modern human species, Homo sapiens, has a very close relationship to another group of primate species, the apes. Humans and the great apes (large apes) of Africa -- chimpanzees (including bonobos, or so-called “pygmy chimpanzees”) and gorillas -- share a common ancestor that lived between 5 and 8 million years ago. Humans first evolved in Africa, and much of human evolution occurred on that continent. The fossils of early humans who lived between 2 and 5 million years ago come entirely from Africa. Most scientists currently recognize some 10 to 15 different species of early humans. Scientists do not all agree, however, about how these species are related or which ones simply died out. Many early human species -- certainly the majority of them -- left no living descendants. Scientists also debate over how to identify and classify particular species of early humans, and about what factors influenced the evolution and extinction of each species. Early humans first migrated out of Africa into Asia probably between 1.6 million and 2 million years ago. They entered Europe somewhat later, generally within the past million years. Species of modern humans populated many parts of the world much later. For instance, people first came to Australia probably within the past 60,000 years and to the Americas within the past 30,000 years or so. The beginnings of agriculture and the rise of the first civilizations occurred within the past 10,000 years. Paleoanthropology Paleoanthropology is the scientific study of human evolution. Paleoanthropology is a subfield of anthropology, the study of human culture, society, and biology. The field involves an understanding of the similarities and differences between humans and other species in their genes, body form, physiology, and behavior. Paleoanthropologists search for the roots of human physical traits and behavior. They seek to discover how evolution has shaped the potentials, tendencies, and limitations of all people. For many people, paleoanthropology is an exciting scientific field because it investigates the origin, over millions of years, of the universal and defining traits of our species. However, some people find the concept of human evolution troubling because it can seem not to fit with religious and other traditional beliefs about how people, other living things, and the world came to be. Nevertheless, many people have come to reconcile their beliefs with the scientific evidence. Early human fossils and archeological remains offer the most important clues about this ancient past. These remains include bones, tools and any other evidence (such as footprints or butchery marks on animal bones) left by earlier people. Usually, the remains were buried and preserved naturally. They are then found either on the surface (exposed by rain, rivers, and wind erosion) or by digging in the ground. By studying fossilized bones, scientists learn about the physical appearance of earlier humans and how it changed. Bone size, shape, and markings left by muscles tell us how those predecessors moved around, held tools, and how the size of their brains changed over a long time. Archeological evidence refers to the things earlier people made and the places where scientists find them. By studying this type of evidence, archeologists can understand how early humans made and used tools and lived in their environments The Process of Evolution The process of evolution involves a series of natural changes that cause species (populations of different organisms) to arise, adapt to the environment, and become extinct. All species or organisms have originated through the process of biological evolution. In animals that reproduce sexually, including humans, the term species refers to a group whose adult members regularly interbreed, resulting in fertile offspring -- that is, offspring themselves capable of reproducing. Scientists classify each species with a unique, two-part scientific name. In this system, modern humans are classified as Homo sapiens. Evolution occurs when there is change in the genes (the chemical molecule, DNA) inherited from the parents and especially in the proportions of different genes in a population. The information contained in genes can change by a process known as mutation. The way particular genes are expressed – that is, how they influence the body or behavior of an organism -- can also change. Genes affect how the body and behavior of an organism develop during its life, and this is why genetically inherited characteristics can influence the likelihood of an organism’s survival and reproduction. Evolution does not change any single individual. Instead, it changes the inherited means of growth and development that typify a population (a group of individuals of the same species living in a particular habitat). Parents pass adaptive genetic changes to their offspring, and ultimately these changes become common throughout a population. As a result, the offspring inherit those genetic characteristics that enhance their chances of survival and ability to give birth, which may work well until the environment changes. Over time, genetic change can alter a species' overall way of life, such as what it eats, how it grows, and where it can live. Human evolution took place as new genetic variations in early ancestor populations favored new abilities to adapt to environmental change and so altered the human way of life. Primates Human beings belong to the mammalian group known as Primates -- the scientific category that contains over 230 species of lemurs, lorises, tarsiers, monkeys of the Old and New World, and apes. Modern humans, early humans, and other primate species all share many similarities and have some important differences. Knowledge of these similarities and differences helps scientists to understand the roots of many human traits and the significance of each development in human evolution. All primates, including humans, share at least part of a set of common characteristics that distinguish them from other mammals. Many of these characteristics evolved as adaptations for life in the trees, an environment in which the earliest primates evolved. These characteristics include more reliance on sight than smell; overlapping fields of vision, allowing stereoscopic (three-dimensional) sight; limbs and hands adapted for clinging on, leaping from and swinging in the trees; the ability to grasp and manipulate small objects (using fingers with nails instead of claws); large brains in relation to body size; and complex social lives. The scientific classification of primates reflects evolutionary relationships among individual species and groups of species. Strepsirhine (meaning "wet nosed") primates -- of which the living representatives include lemurs, lorises, and other groups of species -- are all commonly known as prosimians. Strepsirhines are the most primitive of living primates. They share all of the basic characteristics of primates, although their brains are neither particularly large nor complex and they have a more elaborate and sensitive olfactory system (involved in the sense of smell) then do other primates. The earliest monkeys and apes evolved from ancestral haplorhine (meaning "dry nosed") primates, of which the most primitive living representative is the tarsier. Tarsiers were previously grouped with prosimians, but many scientists now recognize that tarsiers, monkeys, and apes share some distinctive traits, and group the three together. Monkeys, apes, and humans -- who share many traits not found in other primates -- together make up the suborder Anthropoidea. Anthropoid primates are divided into New World (South America, Central America, and the Caribbean Islands) and Old World (Africa and Eurasia) groups. The platyrrhine (broad-nosed) monkeys represent the first, and the second is the catarrhine (downward-nosed) monkeys and apes. Humans belong to this second group. Apes and humans together make up the superfamily Hominoidea, a grouping that emphasizes the close relationship among these species. Scientists do not all agree about the appropriate classification of the families within this superfamily. Living hominoids are grouped into either two or three families: Hylobatidae, Hominidae, and sometimes Pongidae. Hylobatidae consists of the small or so-called lesser apes of Southeast Asia, commonly known as gibbons and siamangs. The Hominidae (hominids) include humans and, according to some scientists, the great apes. For those who include only humans among the Hominidae, all of the great apes, including the orangutans of Southeast Asia, belong to the family Pongidae. Traditionally, the term "hominid" has referred to species of humans that evolved after the split between early humans and other ape lineages. But genetic evidence, which shows chimps and humans to be more closely related genetically (and evolutionarily) to each other than to any other ape, supports placing all of the great apes and humans together in the family Hominidae. According to this reasoning, the evolutionary branch of Asian apes leading to orangutans, which separated from the other hominid branches by about 13 million years ago, belongs to the subfamily Ponginae. The African apes (gorillas, chimpanzees, and humans) are then classified in the subfamily called Homininae (or hominines). And finally, the line of early and modern humans belongs to the tribe (classificatory level above genus) Hominini, or hominins. This classification would be true to the genetic evidence. But it tends to be confusing when learning about the subject, as many similar names (hominoid, hominid, hominine, and hominin) would apply to the different aspects of ape and human evolution. In this article the term "early human" refers to all species of the human family tree since the divergence from a common ancestor with the African apes. Popular writing often still uses the word "hominid" to mean the same thing. Humans as Primates About 98 percent of the genes in people and chimpanzees are identical, making chimps the closest living biological relatives of humans. This does not mean that humans evolved from chimpanzees, but it does indicate that both species evolved from a common ape ancestor. Orangutans, the great apes of Southeast Asia, differ genetically from humans to a greater extent, indicating a more distant evolutionary relationship. Modern humans have a number of physical characteristics indicative of an ape ancestry. For instance, people have shoulders with a wide range of movement and fingers capable of strong grasping. In apes, these characteristics are highly developed as adaptations for brachiation (swinging from branch to branch in trees). Although humans do not brachiate, the general anatomy of that earlier adaptation still remains. Both people and apes also have larger brains and greater cognitive abilities than do most other mammals. Human social life, too, shares similarities with that of African apes and other primates -- such as baboons and rhesus monkeys -- that live in large and complex social groups. Group behavior among chimpanzees, in particular, strongly resembles that of humans. For instance, chimps form long-lasting attachments with each other; participate in social bonding activities, such as grooming, feeding, and hunting; and form strategic coalitions with each other in order to increase their status and power. Early humans also probably had this kind of elaborate social life. However, modern humans fundamentally differ from apes in many significant ways. For example, as intelligent as apes are, people's brains are much larger and more complex, and people have a unique intellectual capacity and elaborate forms of culture and communication. In addition, only people habitually walk upright, can precisely manipulate very small objects, and have a throat structure that makes speech possible. The Fossil Primates The origin of the mammalian group primates is traced back to Plesiadapiformes, the last common ancestors of strepsirhines and other mammals. Plesiadapiformes evolved at least 65 million years ago. They were creatures similar to the modern tree shrews. The earliest primates evolved by about 55 million years ago. The first strepsirhine primates, fossil species similar to lemurs and tarsiers, evolved during the Eocene epoch (about 56 to 34 million years ago). The oldest lineages of catarrhine primates, from which monkeys and apes evolved, are known between 50 and 33 million years ago. A primate known as Propliopithecus (one lineage sometimes called Aegyptopithecus), from the Fayum fossil sites of Egypt, is an archaic-looking catarrhine, and is thought to be what the common ancestor of all later Old World monkeys and apes looked like. So Propliopithecus may be considered an ancestor, or closely related to a direct ancestor, of humans. Hominoids, or members of the superfamily Hominoidea, evolved during the Miocene epoch (24 million to 5 million years ago). Large ape species had originated in Africa by 23 or 22 million years ago. Among the oldest known hominoids is a group of apes known by its genus name, Proconsul. Species of Proconsul had features that suggest a close link to the common ancestor of apes and humans. The ape species Proconsul heseloni lived in dense forests of eastern Africa about 20 million years ago. It was agile in the trees, with a flexible backbone and narrow chest of a monkey, yet capable of wide movement of the hip and thumb as in apes. Early in their evolution, the large apes underwent several radiations, periods when species originated and became more diverse. After Proconsul had thrived for several million years, a group of apes from Africa and Arabia known as the afropithecines evolved around 18 million years ago and diversified into several species. By 15 million years ago, apes had migrated to Asia and Europe over a land bridge formed between the Africa-Arabian and Eurasian continents, which had previously been separated. Around this time, two other groups of apes had evolved – namely, the kenyapithecines of Africa and western Asia (first known about 15 million years ago) and the dryopithecines of Europe (first known about 12 million years ago). It is not yet clear, however, which of these groups of ape species may have given rise to the common ancestor of African apes and humans. The First Humans: The Early Australopiths By at least 4.4 million years ago in Africa, an apelike species had evolved that had two important traits, which distinguished it from other apes: (1) small canine (eye) teeth (next to the incisors, or front teeth) and (2) bipedalism--that is the ability to walk on two legs. Scientists commonly refer to these earliest human species as australopithecines, or australopiths for short. The earliest australopith species known today belongs to the genus Ardipithecus. Other species belong to the genus Australopithecus and, by some classifications, Paranthropus. The name australopithecine translates literally as "southern ape," in reference to South Africa, where the first known australopith fossils were found. Countries in which scientists have found australopith fossils include Ethiopia, Tanzania, Kenya, South Africa, and Chad. Thus, australopiths ranged widely over the African continent. The Great Rift Valley of eastern Africa, in particular has become famous for its australopith finds because past movements in Earth's crust in this region were favorable to environments in which bones are easily preserved and, later, to exposure of ancient deposits of fossilized bones. There are many ideas about why the early australopiths split off from the apes, initiating the course of human evolution. Virtually all hypotheses invoke environmental change as an important factor, specifically in influencing the evolution of bipedalism. Some well-established ideas about why humans first evolved include (1) the savanna hypothesis, (2) the woodland-mosaic hypothesis, and (3) the variability hypothesis. The savanna hypothesis argues that the Miocene forests of Africa became sparse and broken up between 5 and 8 million years ago due to a cooler and drier global climate. This drying trend led to the separation of an ape population in eastern Africa from other populations of apes in the more heavily forested areas of western Africa. The eastern population had to adapt to drier, open savanna environments, which favored the evolution of terrestrial living. Terrestrial apes might have formed large social groups in order to improve their ability to find and collect food and to fend off predators. The challenges of savanna life might also have promoted the rise of tool use, for purposes such as scavenging meat from the kills of predators. These important evolutionary changes would have depended on increased mental abilities and, therefore, may have correlated with the development of larger brains in early humans. Critics of the savanna hypothesis argue against it on several grounds, but particularly for two reasons. First, an early australopith jaw similar to A. afarensis has been found in Chad in west-central Africa, 2500 kilometers west of the African rift valley. This find suggests that australopiths ranged widely over the African continent and that East Africa may not have been fully separated from environments further west. Second, there is growing evidence that open savannas were not prominent in Africa until sometime after 2 million years ago. Criticism of the savanna hypothesis has spawned alternative ideas about early human evolution. The woodland-mosaic hypothesis proposes that the early australopiths evolved in a mosaic of woodland and grassland that offered opportunities for feeding both on the ground and in the trees. Ground feeding then favored regular bipedal activity and, eventually, the evolution of anatomical features of the hip, leg, and foot that assisted this form of locomotion. The variability hypothesis suggests that early australopiths experienced many changes in environment and ended up living in a range of habitats, including forests, open-canopy woodlands, and savannas. In response, their populations became adapted to a variety of surroundings. Evidence from early australopith sites, in fact, shows this range of habitats. So the unique appearance of their skeletons may have allowed them the versatility of living in habitats with many or few trees. From Ape to Human Fossils from several different early australopith species that lived between 4 million and 2 million years ago show a variety of adaptations that mark the transition from ape to human. The very early period of this transition, prior to 4 million years ago, remains poorly documented in the fossil record, but those fossils that do exist show the most primitive combinations of ape and human features. Fossils reveal much about the physical build and activities of early australopiths, but little is known about surface physical features, such as the color and texture of skin and hair, or about certain behaviors, such as methods of obtaining food or patterns of social interaction. For these reasons, scientists study the living great apes -- particularly the African apes -- to better understand how early australopiths might have looked and behaved. The study of living apes, therefore, sheds light on how the transition from ape to human might have occurred. For example, australopiths probably resembled the great apes in characteristics such as the shape of the face and the amount of hair on the body. Australopiths also had brains and body sizes in the same range exhibited by the great apes, leading scientists to believe that the australopiths had similar mental capabilities and possibly even social structures. Australopith Characteristics Most of the distinctly human physical qualities in australopiths related to their bipedal stance. Before australopiths, no mammal had ever evolved an anatomy for habitual upright walking. African apes move around their environments in a variety of ways. They use their arms to climb and to swing through the trees (known as brachiation). They knuckle-walk when on the ground, leaning on the middle parts of their fingers. And sometimes they move on two legs, as when chimpanzees feed on low branches or when gorillas show threat displays. The australopith body was devoted especially to bipedal walking. Australopiths also had small canine teeth, as compared with long canines found in almost all other catarrhine primates. Other characteristics of australopiths reflected their ape ancestry. Although their canine teeth were not large, their faces stuck out far in front of the braincase. Their brains were about the same size as apes' today, about 390 to 550 cubic cm (24 to 34 cubic in) but were enlarged relative to body size. Their body weight, which can be estimated from their bones, ranged from about 27 to 49 kg (60 to 108 lb.) and they stood about 1.1 to 1.5 m (3.5 to 5 ft) tall. Their weight and height compare closely to those of chimpanzees (chimp height measured standing). Some australopith species had a large degree of sexual dimorphism -- males were much larger than females -- a trait also found in gorillas, orangutans, and some other primates. Australopiths also had curved powerful fingers and long thumbs with a wide range of movement. Apes, in comparison, have longer, very strong, even more curved fingers – which are advantageous for hanging and swinging from branches -- but their very short thumbs limit their ability to manipulate small objects. While the fingers were longer than in modern humans, the australopith finger bones were not so long and curved as to suggest arm swinging. It is not yet clear whether these changes in the hand of early australopiths enabled them to use tools in a better way than earlier apes or even modern chimpanzees today. Bipedalism The anatomy of australopiths shows a number of adaptations for bipedalism. Adaptations in the lower body included the following: The australopith ilium, or pelvic bone, which rises above the hip joint, was much shorter and broader than it is in apes. This new shape enabled the hip muscles to steady the body during each bipedal step. The australopith pelvis overall had evolved a more bowl-shaped appearance, which helped support the internal organs during upright stance. The upper legs angled inward from the hip joints, which positioned the knees to better support the body during upright walking. The legs of apes, on the other hand, are positioned almost straight down from the hip, so that when an ape walks upright for a short distance, its body sways from side to side. The australopith foot was also reshaped, including shorter and less flexible toes than an ape's, which provided a more rigid lever for pushing off the ground during each step. Other adaptations occurred above the pelvis. The australopiths’ spine had an S-shaped curve, which shortened the overall length of the torso and gave rigidity and balance when standing. By contrast, apes have a relatively straight spine. The australopith skull also had an important adaptation related to bipedalism. The opening at the bottom of the skull, known as the foramen magnum, where the spinal cord attaches to the brain, was more forward than it is in apes. This position set the head in balance over the upright spine. Australopiths clearly walked upright on the ground, but paleoanthropologists debate about whether the earliest humans also spent a lot of time in the trees. Certain physical features indicate that they spent at least some of their time in the trees. Such features include their curved and elongated fingers and elongated arms. Explaining Bipedalism Many different explanations have been offered to account for the evolution of upright walking. Some of the ideas include: (1) freeing the hands, which was advantageous for carrying food or tools; (2) improved vision, especially to see over tall grass; (3) reducing the body's exposure to hot sun, which allowed better cooling during the day in an open landscape; (4) hunting or weapon use, which was easier with upright posture; and (5) feeding from bushes and low branches, which was easier when standing and moving upright between closely spaced bushes. Although none of these hypotheses has overwhelming support, recent study of chimpanzees favors the last one. Chimps move on two legs most often when feeding on the ground from bushes and low branches. Chimps today are not, however, very good at walking in this way over long distances. As the distances between trees or groves of trees became wider during drier periods bipedal behavior in pre-human populations may have become more frequent. Accordingly, a more effective bipedal gait was favored not as an adaptation to savanna living but rather as a way of crossing less favored areas of open terrain. An ability to climb trees continued to be important. This idea may currently be the best explanation for the unique adaptation of the early australopiths: a combination of long, powerful arms, slightly elongated legs, and lower limbs reshaped for upright walking over long distances on the ground. Small Canine Teeth Compared with apes, humans have very small canine teeth. Apes, particularly males, have thick, projecting, sharp canines that they use for displays of aggression and as weapons to defend themselves. By 4 million years ago, australopiths had developed the human characteristic of having smaller, flatter canines. Canine reduction might have related to an increase in social cooperation among humans and an accompanying decrease in the need for males to make aggressive displays. The Origin of the Genus Homo Origin of the modern human genus, Homo, is one of the most intriguing and controversial questions in paleoanthropology. The oldest fossils of our genus are at least 2.3 to 2.5 million years old. The evolution of the modern human genus can be divided roughly into three periods: early, middle, and late. Species of early Homo resembled the early australopiths in many ways. Some early Homo species lived until possibly 1.6 million years ago. The period of middle Homo began perhaps between 1.8 million and 2.0 million years ago, overlapping with the end of early Homo. Species of middle Homo evolved an anatomy much more similar to that of modern humans but had comparatively small brains. The transition from middle to late Homo evolved large and complex brains and eventually language. Culture also became an increasingly important part of human life during the most recent period of evolution. The key change usually considered to signal the origin of Homo is an increase in brain size, measured by the volume of the inside of the brain case (cranial capacity). The average cranial capacity of modern humans (Homo sapiens) is 1350 cubic centimeters (cc), although the range of variation is large, around 1000 to 2000 cc. In the possible ancestors of Homo (Australopithecus afarensis and A. africanus) brain size was about 350 to 500 cc. What size, it may be asked, defines the difference between the brains of Homo and Australopithecus? Louis Leakey originally argued that the origin of Homo related directly to the development of toolmaking--specifically, the making of stone tools. This once popular idea of "man the toolmaker" considered toolmaking to require certain mental skills and fine hand manipulation that may exist only in members of our own genus. Indeed, the species name Homo habilis (meaning "handy man") refers directly to the making and use of tools. However, several species of australopiths lived at the same time as early Homo, making it unclear which species produced the earliest stone tools. Recent studies of australopith hand bones have suggested that at least one of the robust species, Paranthropus robustus, could have made tools. In addition, during the 1960s and 1970s researchers first observed that some nonhuman primates, such as chimpanzees, make and use tools, suggesting that australopiths and apes that preceded them probably also made some kinds of tools. Furthermore, several early human lineages (including early and later australopiths and possibly Homo) lived at the time of the oldest known stone tools, around 2.5 million years ago. So, scientists are not sure which early humans were responsible for the gradual proliferation of stone tools starting around that time. Still, according to some scientists, early Homo was probably the toolmaker since handheld tools for cutting and pounding were most useful to these smaller-toothed humans, whereas intensive chewing of food inside the mouth was the hallmark of the robust australopiths. Furthermore, stone tools like the oldest known ones continued well after the early australopiths died out. Some scientists think that a period of environmental cooling and drying in Africa set the stage for the evolution of Homo. According to this idea, many types of animals suited to the challenges of a drier environment originated between about 2.8 million and 2.4 million years ago, and these included the first species of Homo. A toolmaking human might have had an advantage in obtaining alternative food sources as vegetation became sparse. The new foods might have included underground tubers and roots and meat obtained through scavenging or hunting. However, the period in question consisted of several fluctuations between dry and wet environments, not just a change to dry. Thus brain enlargement, early stone tool use, and expansion of diet all may have been ways of adapting to unpredictable and fluctuating settings rather than just dry, cool ones. Also, the supposed pulse of species originations and extinctions is not well documented. In short, the exact causes of the origin of Homo are poorly known; future fossil discoveries in this key time period should help in understanding the earliest origin of our genus. Early Homo Paleoanthropologists generally recognize two species of early Homo. The two species, Homo habilis and Homo rudolfensis, overlapped in time and appear to have co-existed in the same region with other early human species. The record is unclear because most of the early fossils that scientists have identified as species of Homo occur as isolated fragments. In many places, only teeth, jawbones, and pieces of skull -- without any other skeletal remains -- indicate that new species of smaller-toothed humans had evolved as early as 2.5 million years ago. Scientists cannot always tell whether these fossils belong to late-surviving gracile australopiths or early representatives of Homo. The two groups resemble each other because Homo likely descended directly from an early species of australopith. Homo habilis In the early 1960s, at Olduvai Gorge, Tanzania, Louis Leakey, anatomist John Napier, and paleoanthropologist Philip Tobias described a newly discovered group of early human fossils that showed a cranial capacity of 590 to 690 cc. Based on this brain size, which was above the range of that known in australopiths, the scientists argued that a new species, Homo habilis, should be recognized. Other scientists questioned whether this amount of brain enlargement was sufficient for applying the genus name Homo, or even whether H. habilis was different from Australopithecus africanus, as the teeth of the two species look similar. However, scientists now widely accept both the genus and species names designated by the Olduvai team. H. habilis lived in eastern and possibly southern Africa between about 1.9 million and 1.6 million years ago, and maybe as early as 2.4 million years ago. Although the fossils of this species somewhat resemble those of australopiths, H. habilis had smaller and narrower molar teeth, premolar teeth, and jaws than did its predecessors and contemporary robust species. A fragmented skeleton of a female from Olduvai shows that she stood only about 1 m (3.3 ft) tall, and her arms were longer relative to her legs than they were the australopith Lucy (A. afarensis). At least in the case of this individual, therefore, H. habilis had very apelike body proportions. However, H. habilis also had more modern-looking feet and hands capable of producing tools. Many of the earliest stone tools at Olduvai have been found with H. habilis fossils, suggesting that this species made them. Scientists have noticed a high degree of variability in body size as more fossils of early Homo were discovered. This could mean that H. habilis had a large amount of sexual dimorphism. For instance, the Olduvai female skeleton was dwarfed in comparison with some other fossils -- exemplified by a sizable early Homo cranium from East Turkana in northern Kenya. However, the differences in size actually exceeded those expected between males and females of the same species, and this finding has helped convince many researchers that another species of early Homo had lived in eastern Africa at around the same time. Homo rudolfensis This second species of early Homo was given the name Homo rudolfensis, after Lake Rudolf (now Lake Turkana), northern Kenya. The best-known fossils of H. rudolfensis come from the area surrounding this lake and date from about 1.9 million years ago. Paleoanthropologists have not yet determined the entire time range during which H. rudolfensis lived. This species had a larger face and overall skull than did H. habilis. The cranial capacity of H. rudolfensis averaged about 750 cc. Scientists need more evidence to know whether the brain of H. rudolfensis in relation to its body size was larger than in H. habilis. A larger brain-to-body-size ratio can indicate increased mental abilities. H. rudolfensis also had fairly large teeth, approaching the size of those in robust australopiths. The discovery of even a partial fossil skeleton would reveal whether this larger form of early Homo had apelike or more modern body proportions. Scientists have found several modern-looking thighbones that date from between 1.8 million and 2 million years ago and may belong to H. rudolfensis. These bones suggest a body size of 1.5 m (5 ft) and 52 kg (114 lb.). Middle Homo By about 1.9 million years ago, the period of middle Homo had begun in Africa. Until recently, paleoanthropologists recognized one species in this period, Homo erectus. Many now recognize three species of middle Homo: H. ergaster, H. erectus, and H. heidelbergensis. However, some still think H. ergaster is an early African form of H. erectus, or that H. heidelbergensis is a late form of H. erectus. The skulls and teeth of early African Homo ergaster populations differed subtly from those of later H. erectus populations from China and the island of Java in Indonesia. These subtle differences seem to parallel the differences that occurred between later humans, including our own species, and H. erectus. Since this appears to be the case, the early African species may be more closely related to modern humans. Homo heidelbergensis has similarities to both H. erectus and the later species H. neanderthalensis, and many paleoanthropologists refer to it as a transitional species between middle Homo and the line to which modern humans belong. Homo ergaster The oldest known appearance of Homo ergaster is in Africa around 1.9 million years ago. This species had a rounded cranium, prominent brow ridge (bony, protruding ridge across the brow above the eyes), small teeth, and other features that it shared with the later H. erectus. Many paleoanthropologists consider H. ergaster a good candidate for an ancestor of modern humans because it also had certain modern skull features, including relatively thin cranial bones. Specimens of H. ergaster are especially well known in the time range 1.6 to 1.7 million years ago. The most important fossil find of this species is a nearly complete skeleton of a young male, dated 1.6 million years old, from West Turkana, Kenya. The sex of the skeleton is determined from the shape of the pelvis and by its brow ridges, and an age of 9 to 12 years at death is known by the pattern of tooth eruption and bone growth. It is not known how the boy died. The "Turkana boy" had long leg bones adapted for long distance walking. The length of his arms, legs, and trunk were proportioned as in modern humans, in contrast with the apelike short legs (and long arms) of H. habilis and A. afarensis. This skeleton is remarkable for the evidence it offers of an early human fully committed to bipedality, with no signs of significant tree climbing. H. ergaster had an elongated body, indicating that it was adapted to hot, tropical climates, just as modern humans from the tropics also tend to have long, slender bodies. An adult height of about 6-ft and a body weight of 150 lbs. is estimated from the Turkana skeleton, assuming that the body underwent an adolescent growth spurt as modern human teenagers usually do. Homo ergaster, H. rudolfensis, and H. habilis add significantly to the known diversity of early human species nearly 2 million years ago. Most paleoanthropologists used to believe that human evolution consisted of a single line that evolved progressively over time, an australopith species followed by Homo erectus, then Neanderthals, and finally modern Homo sapiens. But now it is thought that as many as five different species of early human, including robust australopiths, inhabited Africa about 1.9 million years ago. Since hybridization rarely succeeds between species with significant skeletal differences, only one of these species could have been the ancestor of modern humans. H. ergaster is widely accepted as an ancestor, although it arose from earlier populations of Homo, possibly H. habilis or H. rudolfensis. It appears that periods of species diversity and extinction have been common during human evolution, a similarity to the evolutionary histories of other organisms. Modern H. sapiens has the distinction of being the only living human species today. Homo erectus Paleoanthropologists now know that humans first evolved in Africa and lived only on that continent for at least the first two million years of our evolutionary history. But this finding was not clear to scientists until quite recently. In fact, the first discoveries of early human fossils in the 1800s were in Europe. Later discoveries came from Asia and included fossils from the Indonesian island of Java. The first finds from Java were in 1891 by Dutch physician Eugene Dubois. Dubois named this early human Pithecanthropus erectus, or "erect ape-man". Today paleoanthropologists refer to this species as Homo erectus. H. erectus was the first human species known to have spread in large numbers beyond the African continent. H. erectus appears to have evolved in Africa from earlier populations of Homo ergaster, and then spread to Asia between 1.8 million and 1.5 million years ago. The youngest known fossils of this species, from the Solo River in Java, have been dated to about 50,000 years old. So this species was very successful, both widespread (Africa and Asia) and long-lived, having survived for more than 1.5 million years. H. erectus had a low and rounded braincase that was elongated from front to back, a prominent brow ridge, and an adult cranial capacity of 800 to 1,250 cc, an average twice that of the australopiths. Its bones, including the cranium, were thicker than those of earlier species. Prominent muscle markings and thick, reinforced areas on the bones of H. erectus indicate that its body could withstand powerful movements and stresses. Its body was well adapted for bipedal walking. Although its teeth were much reduced in size from Australopithecus, its lower jaw was still quite thick and rugged looking. In the 1920s and 1930s, the most famous collection of H. erectus fossils was excavated from a cave at the site Zhoukoudian (Chou-k'ou-tien), China, near Beijing (Peking). Scientists dubbed these fossil humans Sinanthropus pekinensis, or Peking Man, but others later reclassified them as H. erectus. The Zhoukoudian cave yielded the fragmentary remains of over 30 individuals, ranging from about 500,000 to 250,000 years old. These fossils were lost near the outbreak of World War II, but anatomist Franz Weidenreich had made excellent casts and descriptions of the finds. Further studies at the cave site have yielded more H. erectus remains. Other important fossil sites of H. erectus in China include Lantian, Yuanmou, Yunxian, and Hexian. Researchers have also recovered many tools made by H. erectus in China at sites such as Nihewan and Bose, and other sites of similar age (at least 1 million to 250,000 years old). Ever since the discovery of H. erectus, scientists have debated whether this species was a direct ancestor of later humans, including H. sapiens. The last populations of H. erectus -- such as those from the Solo River in Java -- may have lived as recently as 50,000 years ago, at the same time as populations of H. sapiens. Although modern humans could not have evolved in that amount of time from these late populations of H. erectus, it is possible that earlier East Asian populations could have given rise to H. sapiens. Homo heidelbergensis Many paleoanthropologists believe that early humans migrated into Europe by 800,000 years ago, and that these populations were not Homo erectus. A growing number of scientists refer to these early migrants to Europe -- who predated both Neanderthals and H. sapiens in the region -- as H. heidelbergensis. The species name comes from a 500,000-year-old jaw found near Heidelberg, Germany. Scientists have found few human fossils in Africa for the period between 1.2 million and 600,000 years ago, during which H. heidelbergensis or their ancestors first migrated into Europe. Populations of Homo ergaster (or possibly H. erectus) appear to have lived until at least 800,000 years ago in Africa, and possibly until 500,000 years ago in northern Africa. When these populations disappeared, other massive-boned and larger-brained humans -- possibly H. heidelbergensis -- appear to have replaced them. Scientists have found fossils of these stockier humans at sites in Bodo, Ethiopia; Saldanha (also known as Elandsfontein), South Africa; Ndutu, Tanzania; and Kabwe, Zimbabwe. There are at least three different ideas about these fossils. Some scientists place the African fossils in the species H. heidelbergensis, and think that this species gave rise to both Neanderthals (in Europe) and H. sapiens (in Africa). Others think that the European and African fossils are distinct, and that the African fossils belong in their own species (not H. heidelbergensis), which gave rise to H. sapiens. Still others prefer the long-held view that H. erectus and H. sapiens form a single evolving lineage, and that the African fossils should be placed in the category of archaic H. sapiens. According this last view, H. erectus was the direct ancestor of modern humans, but the first two views give that role either to H. heidelbergensis, saying that the species spread through Europe and Africa, or to a separate African species. The main point is this: There is a growing number of fossils from Asia, Africa, and Europe that are intermediate between early H. ergaster and H. sapiens, and this makes it hard to decide how to divide up the variation in the bones and to determine which group of fossils represents the most likely ancestor of later humans. Why Did Humans Spread Out of Africa? Humans evolved in Africa and lived only there for as long as 2, or possibly 3, million years. So scientists wonder what finally triggered the first human migration out of Africa (a movement that coincided with the spread of early human populations throughout the African continent). The answer to this question depends, in part, on knowing exactly when that first migration occurred. Some studies claim that sites in Asia and Europe contain crude stone tools and fossilized fragments of humanlike teeth that date from more than1.8 million years ago. Although these claims remain unconfirmed, small populations of humans may have entered Asia prior to 1.7 million years ago, followed by a more substantial spread between 1.7 million and 1 million years ago. The first major habitation of central and western Europe, on the other hand, does not appear to have occurred until between 1 million and 500,000 years ago. By the time of the earliest humans, the world’s continents were in essentially the same positions they now occupy, so continental drift had no impact at all on human dispersal or the origin of races. Migrations were the result of several factors. First, the fall and subsequent rise in sea level occurred repeatedly, especially over the past 2.8 million years, coinciding with the expansion and melting of glaciers. When sea level fell, coastal land area expanded, which included the development of land bridges between continents and islands. Land expansion allowed new areas to be colonized. Second, climate change led to the movement, expansion, and contraction of habitats that were favorable to early humans and other organisms. Migration from one region to another may have simply occurred as early humans tracked climate conditions or habitats to which they were already adapted. Finally, the origin of new adaptive behaviors, such as the ability to control fire or improvement in language communication, may have also resulted in the ability of populations to expand into new types of habitat. Scientists once thought that advances in stone technology could be correlated with the earliest human spread beyond Africa. However, these advances do not seem to be related. By 1.6 million years ago early humans began to make new kinds of tools commonly known as handaxes and cleavers. But this new technology (called Acheulean) was apparently not responsible for the spread, as the earliest human presence in Asia is older than the first handaxes. Also, most of the tool kits from East Asian sites more than 200,000 years old are made up of simply shaped cores and flakes rather than symmetrical handaxes. It's been suggested that the early Pleistocene spread of humans was part of a wider colonization of new regions by meat-eating animals, like lions and hyenas. The dispersal of these African carnivores to Eurasia also occurred during the early Pleistocene, between 1.6 million and 780,000 years ago. Meat-eating may have allowed H. erectus to move through many different environments without having to learn the diverse poisonous plants in different regions. The long dispersal to eastern Asia, however, may have been gradual and occurred through the lower latitudes and environments similar to Africa's. Even a very minor expansion of populations each generation (such as 1 mile every 20 years) would have allowed East African H. erectus to reach Southeast Asia in only 150,000 years. Careful comparison of fossil animals, stone tools, and early human fossils unearthed from African, Asian, and European sites will help to test these ideas. Late Homo The origin of our own species, Homo sapiens, is one of the most hotly debated topics in paleoanthropology. One distinctive group of fossil humans, the Neanderthals, and their relationship to modern humans has been at the center of the debate. Traditionally, paleoanthropologists have classified as Homo sapiens any fossil human younger than 500,000 years old with a braincase larger than that of H. erectus. Many scientists who believe that modern humans descend from a single line dating back to H. erectus use the term "archaic Homo sapiens" to cover a wide variety of fossil humans that predate anatomically modern H. sapiens. Therefore, Neanderthals are sometimes classified as a subspecies of archaic H. sapiens -- H. sapiens neanderthalensis. Other scientists think that the variation in archaic H. sapiens actually falls into clearly identifiable sets of traits, and that any type of human fossil exhibiting a unique set of traits should have a new species name. According to this view, the Neanderthals belong to their own species, H. neanderthalensis. Early Australopiths The australopiths can be divided into an early group of species (sometimes known as gracile australopiths), which arose prior to 3 million years ago; and a later group, known as robust australopiths, which evolved after 3 million years ago. The earlier australopiths -- of which several species evolved between 4.4 million and 3 million years ago -- generally had smaller teeth and jaws. The later robusts had larger faces with large jaws and cheek teeth. A 5-million-year-old jaw fragment with one molar tooth, found in Kenya, and another jaw with two molars, about 4.5 million years old, may be the oldest australopith fossils. But scientists have not yet agreed on the matter since these fossils are so fragmented and do not tell us about the canine teeth or bipedal walking. Several of the early australopiths are given the genus name Australopithecus. Yet some of the oldest finds of australopith bones, dated about 4.4 million years old, have been given a different name because of their very ancient combination of apelike and humanlike traits. These fossils, first discovered in Ethiopia in 1994, are called Ardipithecus ramidus. Ardipithecus ramidus An Ethiopian member of a research team led by paleoanthropologist Tim White discovered the earliest known australopith species in Ethiopia in 1994. These recognizably human fossils were estimated to be about 4.4 million years old. White and his colleagues gave their discovery the name Ardipithecus ramidus. Ramid means "root" in the Afar language of Ethiopia, and refers to the closeness of this new species to the roots of humanity. At the time of this discovery, the genus Australopithecus was scientifically well established. White devised the genus name Ardipithecus to distinguish this new species from other australopiths because it had a very ancient combination of apelike and humanlike traits. The teeth of Ardipithecus ramidus have a thin outer layer of enamel--a trait also seen in chimps and gorillas, but not in other australopith species or most older fossil apes. This trait suggests a fairly close relationship with an ancestor of the African apes. In addition, the skeleton shows strong similarities to that of a chimpanzee but has slightly reduced canine teeth and adaptations for bipedalism. Australopithecus anamensis In 1965 a research team form Harvard University discovered a single arm bone of an early human at the site of Kanapoi in northern Kenya. The researchers estimated this bone to be 4 million years old, but could not identify the species to which it belonged. It was not until 1994 that a research team, led by paleoanthropologist Meave Leakey, found numerous teeth and fragments of bone at the site that could be linked to the previously discovered fossil. Leakey and her colleagues determined that the fossils were those of a very primitive species of australopith, which was given the name Australopithecus anamensis. Researchers have since found other A. anamensis fossils at nearby sites, dating between about 4.2 million and 3.9 million years old. The skull of this species appears apelike, while its enlarged tibia or lower leg bone, indicates that it supported its full body weight on one leg at a time, as in regular bipedal walking. Australopithecus afarensis Australopithecus anamensis was quite similar to another, much better-known species, A. afarensis, a gracile australopith that thrived in eastern Africa between about 3.9 million and 3 million years ago. The most celebrated fossil of this species, known as Lucy, is a partial skeleton of a female discovered by paleoanthropologist Donald Johanson in 1974 at Hadar, Ethiopia. Lucy lived 3.2 million years ago. Several hundred fossils of this species have been described from Hadar, including a collection representing at least 13 individuals of both sexes and various ages, all from a single site that is dated 3.2 million years old. Researchers working in northern Tanzania have also found fossilized bones of A. afarensis at Laetoli, a 3.6 million year old site best known for spectacular trails of bipedal human footprints (and the prints of other animals) preserved in a hardened volcanic ash. These footprints were discovered in 1978 by a research team led by paleoanthropologist Mary Leakey. They provide irrefutable evidence that australopiths regularly walked bipedally. The controversy about how the australopiths moved has mainly focused on Lucy's species A. afarensis. While Lucy certainly walked upright, she stood only 3.5 feet tall and had longer, more powerful arms than most later human species, which suggests that she was also adept at climbing trees. And while the Laetoli footprints were made by bipedal humans, some scientists have argued that the imprints of the heel, arch, and toes are not exactly like those made by modern human feet. In addition, other fossils from Hadar and Laetoli come from individuals much larger than Lucy, up to 5 feet tall. This has caused controversy over whether the entire set of fossils represents one or two species, although most scientists accept the single-species idea since large and small adults, probably male and female, occurred together at the same site at Hadar. Another controversy arises from the claim that A. afarensis was the common ancestor of both later australopiths and the modern human genus, Homo. While this idea remains a strong possibility, the similarity between Australopithecus afarensis and another australopith species -- one from southern Africa, named Australopithecus africanus -- makes it difficult to decide which of the two species gave rise to the genus Homo. Australopithecus africanus Australopithecus africanus thrived in what is now the Transvaal region of South Africa between about 3.5 million and 2.5 million years ago. The anatomist Raymond Dart described this species -- the first known australopith -- on the basis of a fossil discovered in 1924 at Taung, South Africa. For two decades after this discovery, almost no one in the scientific community believed Dart's claim that the skull came from an ancestral human. In the late 1930s and 1940s, teams led by paleontologist Robert Broom unearthed many more australopith skulls and other bones from the Transvaal sites of Sterkfontein and Swartkrans. A. africanus generally had a more globular braincase and less primitive-looking face and teeth than did A. afarensis. Thus some scientists consider the southern species of early australopith to be a likely ancestor of the genus Homo. According to other scientists, however, A. africanus had facial features that mark it on the path to the robust australopiths found later in the same region. Some recent finds from the Transvaal site of Sterkfontein indeed have begun to blur the distinction between the early australopiths and the later robust species. In 1998 a research team led by South African paleoanthropologist Ronald Clarke unearthed an almost complete early australopith skeleton at Sterkfontein. Although it may prove to be a new species, this important find may resolve some of the questions about where A. africanus fits in the story of human evolution. The Later Australopiths By 2.7 million years ago, the robust australopiths had evolved. The robust australopiths represent an intriguing group of early humans because they survived for a long time and were quite common compared to other early human species. They had adaptations that differed from the larger-brained populations of Homo who lived at the same time, but then mysteriously became extinct by one million years ago. Although the word "robust" originally referred to the larger body once believed to exist in these australopiths, they are now known to have been roughly the same size as A. afarensis and A. africanus. Instead, "robust" accurately describes the very massive molar teeth, face, and skull muscle markings that characterized these species. The robust australopiths had megadont cheek teeth -- broad, thick-enameled molars and premolars -- which formed a flattened and worn surface. Their incisor teeth, by contrast, were small. An expanded, flattened, and more vertical face accompanied this emphasis on the back teeth. The combination of broad molars and large face was effective in absorbing the stresses of strong chewing. Along the top of the head was a sagittal crest, a raised area of bone along the skull's midline from front to back, where thick muscles that moved the jaw up and down were attached. The bars of bone along each side of the skull (the zygomatic arches) were positioned far to the side, which allowed huge openings for the chewing muscles near where they attached to the lower jaw. Altogether, these traits indicate very powerful and prolonged chewing of food. A similar expansion in the chewing structures can be seen in other groups of plant-eating animals. Microscopic wear on the teeth of P. robustus and P. boisei appear to support the idea of a vegetarian diet. It is thought that the robust australopiths had a diet consisting of tough, fibrous plant food, such as seed pods and underground tubers. However, chemical studies of fossil bones suggest that the southern species may also have eaten animals. Because they share the features of heavy chewing, the robust australopiths appear to represent a distinct evolutionary group of early humans. Many paleoanthropologists have linked the robust species together with a unique genus name, Paranthropus (the name originally given to the southern robust species). This classification implies that the first robust species, P. aethiopicus, became separated from the other australopiths and then evolved into P. boisei and P. robustus (the other two robust species). Other researchers have kept the robust species within the genus Australopithecus, stating that the eastern forms (A. aethiopicus and A. boisei) evolved their massive teeth from the early australopiths of the region (perhaps A. afarensis), whereas the southern species (robustus) evolved independently from A. africanus. If this type of parallel evolution occurred, the robust species would form two separate side branches of the human family tree. Due to alternative views such as this, the robust species are often known by more than one name (such as Australopithecus boisei and Paranthropus boisei). Paranthropus aethiopicus The earliest known robust species, Paranthropus aethiopicus, had evolved in eastern Africa by 2.7 million years ago. In 1985 at West Turkana, Kenya, paleoanthropologist Alan Walker discovered the fossil skull that defined this species. It became known as the "black skull" because of the color it had absorbed from minerals in the ground. The skull, dated 2.5 million years old, had a tall sagittal crest toward the back of its cranium and a face that projected far outward from the forehead. P. aethiopicus shares some primitive features with A. afarensis -- that is, features that originated in the earlier East African australopith. This may indicate that P. aethiopicus evolved from A. afarensis. Paranthropus boisei Paranthropus boisei, the other well-known East African robust australopith, lived over a large geographic range between about 2.3 million and 1.2 million years ago. In 1959 Mary Leakey discovered the first fossil of this species -- a nearly complete skull at the site of Olduvai Gorge in Tanzania. Paleoanthropologist Louis Leakey, husband of Mary, named the new species Zinjanthropus boisei (Zinjanthropus translates as "East African man"). This skull, which is dated to 1.8 million years ago, has the most specialized features of all the robust species. It has a massive, wide, and dished-in face that was capable of withstanding extreme chewing forces, and its molars are four times the size of those in modern humans. Since the discovery of Zinjanthropus, now recognized as an australopith, scientists have found great numbers of P. boisei fossils in Tanzania, Kenya, and Ethiopia. Paranthropus robustus The southern robust species, which has the descriptive name Paranthropus robustus, lived between about 1.8 million and 1.3 million years ago in the Transvaal, the same region that was home to A. africanus. In 1938 Robert Broom, who had found many A. africanus fossils, bought a fossil jaw and molar that looked distinctly different from those in A. africanus. After finding the site of Kromdraai, from which the fossil had come, Broom collected many more bones and teeth that together convinced him to name a new species, which he called Paranthropus robustus (Paranthropus meaning "beside man"). -Savage Science

Addressing some misconceptions and explaining some of the basics. http://www.youtube.com/watch?v=vss1VKN2rf8&feature=player_embedded Here is a great link to several places u can learn what evolution is about from people who are scientists. http://www.youtube.com/user/WhyEvolutionIsTrue "There is grandeur in this view of life, with its several powers having been originally breathed into a few forms or into one; and that whilst this planet has gone cycling on according to the fixed law of gravity from so simple a beginning endless forms most beautiful and most wonderful have been and are being, evolved" - Charles Darwin -

This week the 200th aniversary of Darwin's birth is celebrated.

anybody here interested in reading books related to psychological sciences???????? then whats ur favourite book????? one of my favourites is Justin leiber's-"STRUCTURALISM"

Anyone interested in mathematics and want math puzzles with chess puzzles. ? Join the group "I want 2 do Maths" . It is really interesting group. We have puzzles daily and will get rank who solved it correctly . We will have many interesting features in the group. Here is the link -----------------------------------------------------------------------------

Hi guys, I've been reading your posts on all sorts of things and it seems that I have joined a group with pretty good knowledge on all sorts of topics. Pleasant change! Here is my question According to special relativity, which deals with uniform motion ( yes, I know it can deal with accelearation but uniform motion is what I want to talk about here) states that person "A" can consider himself a rest with respect to person "B" and person "B" can consider himself at rest with respect to person "A" as long as they stay in uniform motion. If A and B have identical light clocks and are separated by some distance, say A in space and B on the Earth, and A is traveling at a uniform speed, then B, on the Earth, could say that it is he who is moving and not A. OK so far so good? Lets say that A is moving at some speed with respect to B. B now measures the rate at which A's clock is now "ticking" he finds that it has slowed down with respect to his own identical clock. (If you decided to input any speed into the equations it will not matter what speed you input, as long as it is less than the speed of light.) So lets say that B finds out that A's clock is half as slow as his own clock. This would then be an indication of time dilation. BUT, lets now say that A decided to say that it was he who is at rest with respect to B and decides to measure B's clock with respect to his own. He finds that B's clock is "ticking" half as slow as his own clock! As far as I can tell both clocks are "ticking" at the same rate. If this is true that both clocks are ticking at the same rate then where is the time dilation? If you need me to rephrase anything just let me know. Thanks for reading. Red

well sence I'm resigning I have decited to give the group to,                  mr_blonde, so he will be controling this group, have fun p.s. and I did do that on purporse, so..., yah.

Hi folks, just wanted to know if this group is still active, are there any members who still post on this group? Red

Well, I've been campaigning for "Best Group Manager of the Year" for many months now, but since Chesskween has thrown her hat into the mix, I haven't been able to post a single comment anywhere. I'd feel too guilty competing against her. So I'm switching my campaign to "Member of the Year" since it's the only other one that I'm in contention for (although I was a lot closer in the other one). Good Luck Jane. I'll tell people to vote for you. I hope you do the same for me. Click here to vote on Chess.com Site Trophies go to page 3 Please vote: Best Group Manager of the Year - Chesskween Most Enthusiastic Beginner of the Year - Melanerz Chess.com Member of the Year - Billium248 Thank You.

what is time I have always thought of it as the passing of the body form one moment to the nextThanks to Bill I am now posting this here also, maybe I'll be a bit more active in this group than others

here is the idea we get a tournament going and we ask each other science questions till one gives and the first 1 is a person who runs the group and the runner-ups get to be admins, good idea? or not....

I don't wabnt to take biology but I need it to pass high school, any ideas how I can skip it, I also need the credit........

erik said that they are working on group tournaments would everyone be intrested? or should I just kill the idea?

books, does anyone know any good books, my favorite book is, "how in the world?", yours?

What is the status of the fossil "nano-bacteria" from Mars?