Laelaps

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Two restorations of “Ardi”, a 45% complete skeleton of Ardipithecus ramidus published in this week’s issue of Science. Restorations (including the full skeletal restoration below) by artist Jay Matternes.

The stories of “Ida” and “Ardi” could hardly be more different.

Ida was a lemur-like primate that lived 47 million years ago in an area that is now Messel, Germany. Ardi was much closer to us; she was one of the earliest hominins and lived 4.4 million years ago in what would become known as Ethiopia.

When the bones of Ida were discovered they were held in a private collection for years before being sold for an undisclosed sum to paleontologist Jorn Hurum. The first bones of Ardi were found in the field in 1992 by paleoanthropologist Gen Suwa. Enough fossils were found for an initial publication two years later, but the search continued for years afterward. That search has yielded over 100 bones from Ardi’s kind, representing about 36 individuals. Ardi is the most complete individual, with about 45% of the skeleton intact.

From almost the time of her acquisition by Hurum, Ida was groomed to be a star. The media company Atlantic Productions began to work with Hurum and immediately started the production of a book, several documentaries, and a bombastic public unveiling of a discovery they said would “CHANGE EVERYTHING.” The scientists describing Ida were forced to rush their study to meet the deadline set by the company The bones of Ardi and her kin, by contrast, were scrutinized with great detail over 15 years. So secret was the study of her bones that some frustrated paleoanthropologists called it the “Manhattan Project of anthropology.”

Ida was introduced to the public as the “ancestor of us all”, but the science behind this claim was flimsy. She was more closely related to lemurs than to us. Ardi, however, sits relatively close to the base of the human (i.e. hominin) family tree. Whether our species can trace its ancestral heritage back through hers will be something that will be debated in the months and years to come, but she is nevertheless one of our closest extinct relatives.

Ardi, of course, is short for Ardipithecus ramidus, one of the earliest hominins found to date. Her skeleton (see image below), as well as bits and pieces of other skeletons of the same species, were described this week in a special edition of the journal Science. While a close relative of Australopithecus afarensis (made famous by “Lucy”), Ardipithecus ramidus is about half a million years older than the earliest Australopithecus afarensis and is a bit closer to the last common ancestor between living chimpanzees and humans.* As such the remains of Ardi and her kind give us a closer look at how some of the earliest humans evolved.

*[I apologize if these technical names are cumbersome, but they are important. There are only a few hominin genera but many species, and when talking about Ardipithecus it is important to distinguish between the species given attention in this post, Ardipithecus ramidus, and its older sister species Ardipithecus kadabba.]

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Contrary to the tirades of creationists, paleontologists have identified many evolutionary transitions in the fossil record, and the early history of hominins presents us with some of the most compelling evidence for evolutionary change. The nearly 45% complete skeleton of Ardipithecus ramidus, along with numerous other skeleton fragments from the same species, will enhance our understanding of what our earliest human relatives were like. Depending on your expectations, the skeleton is either very surprising or is consistent with ideas that have been kicked around for some time now.

One of the BIG questions in paleoanthropology, the kind that grabs the attention of the public as well as researchers, is “What was the last common ancestor of chimpanzees and humans like?” The traditional view is that the last common ancestor was a chimpanzee-like knuckle-walker, thus meaning that living chimpanzees are evolutionarily conservative (or have not changed much) while humans have changed radically. A key feature that makes us different from our closest ape relatives is our habitually bipedal posture. How, when, and why did early humans rise up off their knuckles and stand tall?

I say “stand tall” because there has long been an element of mythic storytelling in hypotheses involving the origins of our kind. We want to know the moment our ancestors went from “dumb monkeys” to “noble apes.” (See the book Narratives of Human Evolution for more on this.) As such the origin of bipedalism has often been attributed to the beginnings of other “defining” human characters. Our ancestors stood up to free their hands to gesticulate and carry tools, to allow mothers to carry babies more comfortably, to let them see predators and potential prey in the tall grass of the savanna, &c., &c. &c. The emphasis has long been on why our earliest ancestors stood up, but Ardipithecus ramidus suggests that they were already standing upright when they came down from the trees.

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Since the discovery of “Lucy” paleoanthropologists have recognized that the early australopithecines, a diverse group of hominins including both our ancestors and other now-extinct lineages, had their hands in the trees and their feet on the ground. They had long arms with curved fingers suited to climbing in trees yet from the hips down they were adapted to walking bipedally. When the remains of even older hominins were found, like the ~6 million year old Orrorin tugenensis from Kenya and the controversial ~7 million year old hominid Sahelanthropus tchadensis from Chad, they too appeared to posses some traits related to bipedalism. The problem was that these older fossils were very incomplete; Orrorin is represented by a few carnivore-gnawed scraps and Sahelanthropus by a skull and a few teeth. More complete skeletons would be needed to see to what extent early hominins possessed bipedal and arboreal traits. Ardipithecus ramidus does so nicely.

Much like Australopithecus afarensis, Ardipithecus ramidus had upper-body traits that exhibit adaptation to life in the trees while it had relatively broad hips more consistent with bipedal locomotion. The arms of Ardipithecus ramidus were very long (it could put its hands on its knees standing up; take a moment and try to do the same) and it had hands tipped in curved fingers well-adapted to grasping branches (see image to the upper left). It does not appear to have moved through the canopy by swinging from limb to limb, like a gibbon, but instead moved through the trees on all fours, grasping the branches below it rather than hanging from those above.

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The hips of Ardipithecus ramidus, however, suggest that it probably spent a good deal of time walking upright. (See image to the left. Grey reconstruction is Ardipithecus ramidus. Yellow is Australopithecus afarensis.) In knuckle-walking apes like chimpanzees the blades of the pelvis are flat and come up over the back. In Ardipithecus ramidus the blades of the pelvis form are somewhat more bowl-shaped, a shape that helps hold the viscera of the abdomen in place in hominins that were constantly walking upright. The arrangement in Ardipithecus ramidus did not provide as much support as in our own genus, Homo, or even later australopithecines, but it offered more support than the same bones in chimpanzees. (It should be noted, though, that this interpretation is already controversial.)

The femur, or thigh bone, may also provide a crucial clue to the bipedal habits of Ardipithecus ramidus. Based upon the skeletal restoration published in the Science papers the femur this hominin was oriented to meet the knee-joint at an angle. It might not look like it when you view your own legs, but if you could see your own skeleton when you stood up straight you would see the same orientation, only to a greater extent. This, along with the development of muscles between the top of the femur and the hip, are essential to keeping balance while walking upright.

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This does not mean that Ardipithecus ramidus walked upright all the time or walked like we do, however. It probably only walked upright while on the ground, preferring to move on all fours by grasping while in the trees, and the muscles important to stabilization while walking were not as developed as in later, habitually bipedal hominins. Ardipithecus ramidus also had a very ape-like foot (see image to the left) with a divergent big toe. In our foot our big toe is in line with the rest and assists with the big push-off at the end of a step. Ardipithecus ramidus lacked this adaptation for walking on the ground. Between its foot morphology and lesser development of the hip muscles for balance, Ardipithecus ramidus may have even slightly swayed side to side while walking.

Yet there was an important difference between the foot of Ardipithecus ramidus and that of living chimpanzees and gorillas. The living African apes have flexible feet useful for grasping, almost like a second pair of hands. In monkeys and other primates, however, a particular bone (the os peroneum) embedded within a foot tendon helps keep the foot rigid, especially when jumping from one surface to another. According to the authors of the study, our close ape relatives have lost this “rigid foot” adaptation while our species has retained it. It appears that Ardipithecus ramidus had this “rigid foot” mechanism too, and this relatively simple trait might have had a major effect on its ability to walk on land. Being able to keep a rigid foot while walking on the ground might have been a subtle feature that nevertheless had great importance as early hominins began to walk on the ground more often.

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In general, though, it appears that the adaptations that allowed Ardipithecus ramidus to walk upright on the ground were exaptations. Adaptations that its ancestors possessed for life in the trees were advantageous to walking on the ground and were modified to fit a more terrestrial lifestyle. Pre-existing adaptations to life in the trees were put to new use on the ground and began to be shaped by this new mode of life.

But why would Ardipithecus ramidus have walked on the ground so often? What pressures caused the selection of bipedal traits? These questions are difficult to answer, but the scientists behind the descriptive papers hypothesize that Ardipithecus ramidus was a more generalized feeder than living chimpanzees. It did not go as high up into the canopy in search of fruit, and instead ate a wider variety of food more often, something that drew it to the ground. This hypothesis might be able to be tested by looking at what istopes are preserved in the teeth of Ardipithecus ramidus, but even then we can’t necessarily be sure we’re asking the right questions. I have no doubt these questions will be debated for some time to come.

The hypothesis that Ardipithecus ramidus was arboreally-adapted but did not knuckle-walk, however, is consistent with recent studies that suggest that knuckle-walking was not the ancestral mode of locomotion in the last common ancestor of humans and chimpanzees. In fact, slight differences in the way that gorillas and chimpanzees knuckle-walk may even mean that this “typical” ape mode of locomotion evolved more than once. And while most of the focus has been on Ardipithecus ramidus, the constellation of traits we see in its skeleton may suggest that living chimpanzees are more evolutionarily specialized than we previously thought. What we need to find are early fossil chimpanzees; their side of the family tree is practically blank. Being able to compare early humans with early chimpanzees would tell us much about the evolution of both groups.

There is plenty more that could be said (and certainly will be said) about Ardipithecus ramidus, but the question many people want answered is “How does it fit into our family tree?” The answer is not as straightforward as you might think, and whatever we say now will have to be tested against new discoveries. It will be important to compare even earlier fossil humans and chimpanzees to Ardipithecus ramidus to test what we hypothesize today.

Ardipithecus ramidus is more similar to other early hominins, like australopithecines, than chimpanzees. This makes it one of our early human relatives, but a question remains; was it ancestral to us or does it simply represent the form our true hominin ancestors exhibited at one point in time? Tim White, one of the lead architects of the Ardipithecus ramidus analysis has long favored a straight-line-progression of early hominins, and he slots Ardipithecus ramidus into this sequence. (See his recent essay in The Paleobiological Revolution.)

If White’s view is correct, Ardipithecus ramidus would be a chronospecies, or a particular stage in a direct, gradual line of descent that did not have any side branches or splits. This would mean that paleoanthropologists are looking at different forms of a single species at different points in time. As such Ardipithecus ramidus would not have evolved as a result of a speciation event but would instead represent a particular “phase” in a narrow line of hominin evolution. Ardipithecus kadabba transitions to Ardipithecus ramidus which shades into Australopithecus anamensis which turns into Australopithecus afarensis, after which the human evolutionary tree splits between the earliest members of the genus Homo and other australopithecines.

The idea that early hominins shaded into one another in a straight line of descent requires substantial evidence to corroborate. Based upon what we see elsewhere in the fossil record, and even among living species, it is difficult to believe that there were no speciation events that resulted in ancestor species and descendant species living side-by-side for a time. We expect splits, and it may be that what appears to be a straight chain of evolution is only that way because we are still dealing with an incomplete record in terms of time and biogeography. It is also difficult to be sure of direct ancestor-descendant relationships when dealing with extinct organisms, and this is true of hominins just as well as other extinct vertebrates. (White’s complaints about “cladists” aside.) We want to know whether this or that early hominin was ancestral to us, but in many cases we cannot know for sure. I have no doubt that there are plenty of other early hominins to be discovered, and as they are found it I would expect a “bushier” picture of human evolution to emerge.

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Three hypotheses of early hominin evolution. Top – That there was a straight line of hominin evolution, each “species” being the phase or grade of one true natural species. Middle – A single line of hominin evolution with a speciation event in the same area in which the earliest Australopithecus split from Ardipithecus ramidus. Bottom – Ardpithecus ramidus as one of the last members of a more archaic lineage which existed after a speciation event elsewhere in Africa that gave rise to the first Australopithecus. Published in this week’s issue of Science.

While the authors of the present study seem to prefer Ardipithecus ramidus as a “chronospecies” between Ardipithecus kadabba and Australipithecus anamensis (a hominin known from fragmentary remains thought to be intermediate between Ardipithecus and Australopithecus afarensis), they do present two alternative hypothesis (though not in much detail). There may have been some sort of speciation event between the last Ardipithecus and the first Australopithecus, either within the same geographical area or outside it, and either of which could falsify the idea that there was just one lineage of hominins evolving in a gradual fashion in one place. It may even be that Ardipithecus ramidus represents a remnant of an earlier evolutionary split among the earliest hominins. Future discoveries will be needed to test these ideas, but at the moment I must admit that the “chronospecies” pattern preferred by White is a little difficult for me to swallow. It would appear to be consistent with the evidence at present, but I very much doubt that all the relevant evidence is in yet.

Arguments over the tempo and mode of evolution aside, the assorted collection of Ardipithecus ramidus fossils are very impressive and will no doubt be important to our understanding of early human evolution for many years to come. While some have said that the new fossils are more important than “Lucy”, I think this is a mistake. Ardipithecus ramidus is so impressive because of the mosaic of features it exhibits when compared to other early hominins and living apes (including us). It is best understood as part of an transitional series in which the evolution of particular features can be tracked. If anything, the fossils of Ardipithecus ramidus make the bones of other early hominins more important; by comparing them to each other that we can achieve a better understanding of our own evolutionary heritage.

[If the discussions on blogs are not enough to keep you busy, log onto Facebook between 12 PM and 2 PM (eastern time) tomorrow to talk about Ardipithecus ramidus with science writers Ann Gibbons and Elizabeth Culotta. They have written some excellent and easily-accessible summaries about this hominin. You can join in by visiting the ScienceNOW page on Facebook. To get the papers summarized in this blog post, visit the special Ardipithecus ramidus webpage hosted by Science.]

Comments

  1. #1 a lurker
    October 2, 2009

    Is anyone surprised that Casey Luskin is now ranting? He is taking that it was too crushed route supported by quotes (what else?) about it being crushed without any actual evidence that it is actually too crushed.

  2. #2 DeLene
    October 2, 2009

    Thanks for this wonderfully detailed post! A few things I am not clear about: 1.) If upright/bipedal locomotion was really secondary to climbing in the trees on all fours, then is the illustration being circulated perhaps a tad misleading to the general public? Would it not be more accurate to show both locomotion techniques (one illustration in the trees, another on the ground?) 2.) How can lay people like me assess the strengths/weaknesses of the fossil’s digital assimilation via CT scans? How do we know they really got the details right, like muscle attachments for example? Thanks for your tweets too, my learning curve is vertical today.

  3. #3 Laelaps
    October 2, 2009

    DeLene; I have to keep this short as I’m headed out the door, but I will try to answer in more detail later.

    1) The illustration at the top of the post (the one being published everywhere) shows Ar. ramidus in a standard anatomical position used for many human skeletons. You are right, though, in that it may give the impression that Ar. ramidus stood and moved just like us. A dual illustration of actual movement in the trees/on the ground would have been great.

    2) As for the public knowing that the scientists got the details right, unfortunately that is something that comes down to how much a person knows or is willing to learn. Blogs can play a role here (John Hawks – see blogroll – has already posted a detailed, skeptical analysis). As for restoration of the skull using CT scans, etc. that can be tricky business, and it is best to regard these announcements as hypotheses. I have no doubt we’ll hear more about Ar. ramidus in the future so it is good to keep your ears open for more studies/news as other scientists get to study the same materials. Some of the technical elements may not be accessible to everyone, but I would hope that people would be able to identify that this study is changing old hypotheses and proposing new ones. That’s an understanding of the way science works that is all too rare.

  4. #4 DeLene
    October 2, 2009

    Thanks, very helpful responses & a good dose of healthy perspective. I have added your blog to my Google Reader and will check back frequently.

  5. #5 Carl
    October 2, 2009

    Very detailed and well written post Brian. It’s also wonderful to see magnificent new Jay Matternes artwork.

  6. #6 Laelaps
    October 2, 2009

    Carl; Thank you!

    And I love Jay’s work. His restorations of Amphicyon are among my favorite bits of paleo-art.

  7. #7 Mike Keesey
    October 2, 2009

    Nice coverage.

    While a close relative of the famous “Lucy” (Australopithecus afarensis), Ardipithecus ramidus is about half a million years older

    “Ardi” is about a million years older than “Lucy”. Or were you referring to the time between the species as wholes?

    Based upon what we see elsewhere in the fossil record, and even among living species, it is difficult to believe that there were no speciation events that resulted in ancestor species and descendant species living side-by-side for a time.

    Both could be true. The Afar hominins could represent the main “trunk”, more or less, and there could still be speciation, with various branches off of this trunk (Praeanthropus bahrelghazali? Sahelanthropus tchadensis?). Not saying I support that — it doesn’t seem to me there’s enough evidence to tell one way or the other.

  8. #8 Laelaps
    October 2, 2009

    Mike; Thanks. I had meant to change my wording about the “Lucy” bit but forgot to do it. Hopefully things should be a little better now. Such are the perils of trying to make things accessible by tapping into things people might already be aware of.

    And I agree that we still don’t have a complete picture of early hominin evolution. I have just found White’s criticisms of “cladists” and insistence on a straight, unbranching line a little strange. Obviously the Afar hominins are very important to figuring out early human evolution, but I am skeptical of the idea that there were no speciation events between Ar. kadabba and A. afarensis as White and team seem to prefer. As always, we need more fossils!

  9. #9 David Marjanović
    October 2, 2009

    Well, does Ardipithecus ramidus have any autapomorphies that its according-to-White descendants lack, or not? If not, the chronospecies idea is a viable option. If it does have some, the chronospecies idea has to overcome parsimony to some degree.

    Isn’t that described in the papers? (Sorry, haven’t been able to read them yet.) Because… it ought to be.

  10. #10 scripto
    October 2, 2009

    Thank you. Thank you. Thank you. Particularly for breaking down those three hypotheses. Great stuff.

  11. #11 dorothy
    October 2, 2009

    I think that ardi is important in her own way, after all she gives us an insight as to when we may have started “standing tall.”

  12. #12 DarkSyde
    October 3, 2009

    Great post, can’t believe I missed this when I was rooting around last night for stuff to link to.

  13. #13 Steven
    October 3, 2009

    I am wondering about dentation. Does the new spicies have short canines that would indicate the use of hand-held weapons? That would be as important a pre-adaption for sevannah life as bi-pedal walking.

  14. #14 BrianR
    October 3, 2009

    Very nice post … it’s great to have posts like these as reference later during the inevitable science-and-media discussions. Well done.

  15. #15 Cornelis van Maanen
    October 5, 2009

    As so many do, I wonder about the last developments!

  16. #16 Constant Gina
    October 5, 2009

    Ignoring, for a moment, the inevitable obfuscatory asshattery of the creonuts, that’s one beautiful, beautiful fossil, and a beautiful piece of work on the part of the researchers.
    Slow-cooked science for the win.

  17. #17 Zach Miller
    October 5, 2009

    Great rundown, Brian. Gotta say, though, that’s possibly the worst graphical representation of a phylogeny I’ve ever seen. It doesn’t look like a tree, a bush, or a series of straight lines. It looks like a cross-section of the large intestine.

  18. #18 Françoise Ibarrondo
    October 6, 2009

    I agree perfectly with you, Zach, with your funny large intestine representation of phylogeny. But now, big work, I have to read carefully this long post on “Ardi”

  19. #19 Boesse
    October 7, 2009

    Going back to anagenesis for a moment… granted, I agree that the homonid fossil record is pretty incomplete, *but* for the moment we’ll ignore that. Cladogenesis v. anagenesis – I’m not familiar with White’s complaints of cladists, but I personally favor anagenesis as a viable option in many fossil cases where no evidence of cladogenesis exists.

    If no evidence of cladogenesis exists, anagenesis is more or less the null hypothesis (i.e. = NOT cladogenesis). Does this sound out of line? Granted, this requires a decent record.

    I’ve had many discussions about this subject with fellow MSU students (who had talks on Triceratops anagenesis at NAPC this summer -hi John!) and within dino-mania, there’s such an emphasis placed on crazy whacked out dinosaur diversity that folks overlook simpler versions of evolution such as anagenesis (and in some cases, are reluctant to admit it happens). So, in cases such as this, I understand why White may have some reservations about ‘cladists’. Cladistics is great and all… but it isn’t the end-all, be-all final answer for studying the tempo and mode of evolution. Feel free to tear into me now…

  20. #20 Paul Jones
    November 4, 2009

    Thanks for this great article. I wonder about the argument that knuckle-walking convergently evolved in both gorillas and chimps. I imagine that as genetic-translation improves we might be able to test this by comparing genomes or by looking at their ancestral bones (if we ever find any). While we’re still at a speculative phase, it’s as easy and as explanatory to posit bipedalism having evolved twice! — In a different speculative vein, it’s always struck me that wielding big sticks or hurling stones is next to impossible while you’re on all fours. For a medium sized, slow and ill-defended arboreal ape to take advantage of the wealth of resources to be found at ground-level, sticks and stones, perhaps used cooperatively, might have given the upright ardipithecus the competitive edge. This might explain the diminished tooth size as well.

  21. #21 Inna Burnett
    July 21, 2010

    If the earlierst common ancestor of humans and chimpanzees was Ardi or some other species that was also upright, then it would be logical to conclude that chimps diverged from that ancestor and evolved quadrapedalism as a more recent trait, which is, perhaps, a more advanced and efficient mode of locomotion.

    This could probably challenge and reverse the common assumption that the earlist common ancestor was a chimp-like knuckle walking species.

  22. #22 Inna Burnett
    July 21, 2010

    I think, when we talk about the common human-chimp ancestor, it’d be better to talk about the common ancestor of the entire primate family. Because once we find well-preserved remains of the common human-chimp ancestor, that’ll enable us to adaquently reproduce its structure, we’ll be totally confused as to what the common ancestor of apes and monkeys looked like.

    If the earliest hominid species, which are very close to the common human-chimp ancestor on the time scale, possessed a combination of modern chimp and modern human characteristics, then it’s possible that at one point humans, apes and monkeys shared similar traits, which were a compilation of different features all of us currently possess. So our common ancestor must have looked like a total freak. And then questions don’t stop there.. What did the monkey’s ancestors looked like, and who did they share a common ancestor with anyway?

  23. #23 altın çilek
    February 23, 2011

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  24. If White’s view is correct, Ardipithecus ramidus would be a chronospecies, or a particular stage in a direct, gradual line of descent that did not have any side branches or splits. This would mean that paleoanthropologists are looking at different forms of a single species at different points in time. As such Ardipithecus ramidus would not have evolved as a result of a speciation event but would instead represent a particular “phase” in a narrow line of hominin evolution. Ardipithecus kadabba transitions to Ardipithecus ramidus which shades into Australopithecus anamensis which turns into Australopithecus afarensis, after which the human evolutionary tree splits between the earliest members of the genus Homo and other australopithecines.

    The idea that early hominins shaded into one another in a straight line of descent requires substantial evidence to corroborate. Based upon what we see elsewhere in the fossil record, and even among living species, it is difficult to believe that there were no speciation events that resulted in ancestor species and descendant species living side-by-side for a time. We expect splits, and it may be that what appears to be a straight chain of evolution is only that way because we are still dealing with an incomplete record in terms of time and biogeography. It is also difficult to be sure of direct ancestor-descendant relationships when dealing with extinct organisms, and this is true of hominins just as well as other extinct vertebrates. (White’s complaints about “cladists” aside.) We want to know whether this or that early hominin was ancestral to us, but in many cases we cannot know for sure. I have no doubt that there are plenty of other early hominins to be discovered, and as they are found it I would expect a “bushier” picture of human evolution to emerge ı am read ı am learn thanks ı am like gastirizon design

  25. #25 Inna Burnett
    March 7, 2011

    It’s possible that either Lucy or Ardi never had any mates or offsprings. In this case, their lineages could’ve ended with them, therefore creating no direct descending connection to modern humans. On the other hand, there might be a possiblity that either or both of them could’ve mated with some ancestral chimpanzee species that at the time could’ve been closer related and having more resemblance to Ardi or Lucy than to modern chimpanzees, thus producing semi-hybrid offsprings. The lineage from these semi-hybrid offsprings could’ve survived until present, if it was not weeded out by some other hominid species a long time ago.

    However, if one reverses the direction of the evolutionary tree, and starts drafting it with modern humans going back in time, tracing the evolution of EACH person’s family tree, they’ll notice that just 5 generations ago, every individual had a total of 32 great great great grand parents they directly descended from, and who contributed to that individual’s gene pool, on the maternal and paternal sides combined. Multiplied by 2 in each subsequent generation, this number reaches an immense proportion just in 7 generations moving backward.

    This is what it looks like –
    Each person has:
    2 parents
    4 grand parents (2 maternal and 2 fraternal)
    8 great grand parents
    16 great great grand parents
    32 great great great grand parents….

    Also, according to the principles of genetics, you inherit
    %50 of each of your parents genes, making it %25 from each grand parent. Divide this %25 by 2 in each consequent generation, and you’ll get less than %3 of each of your 32 great great great grand parents’ genes, meaning that the species you descended from 10 generations ago, have contributed only less than %1.0 of their genes to your genenetic makeup.

    To top this, genetic analysis shows a relatively small
    (%1.0 – %1.5) genetic difference between modern humans and modern chimpanzees. I hope my calculations are wrong, and it doesn’t mean that humans split from chimps only 5 or 6 generations ago, because that would definitely make a lot of people extremely furious. Though this might provide some support for the religious assumption that the universe is only 5,000 years old, if proven, of course.

  26. #26 CPR
    April 12, 2011

    The confusions, controversies and arguements that follow the latest discovery of skeleton in S/Africa simply vindicates the Holy Bible. When the story first emerged the exaggeraion among atheistic media and pagan scientists were so much that the gullibles started celebrating the percieved defeat of the Holy Bible. But now the world of science is even questioning some fundamental aspects of the theory of Darwinism in view of more advanced analysis of the skeleton. The Holy Bible has already said, “a *** has said in his mind that: There is no God”

  27. #27 canlı maç izle
    March 14, 2012

    he exaggeraion among atheistic media and pagan scientists were so much that the gullibles started celebrating the percieved defeat of the Holy Bible. But now the world of science is even questioning some fundamental aspects of the theory of Darwinism in view o

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