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Science

Earliest Primate Placed With Dinosaurs 57

Quirk writes "National Geographic has a piece suggesting the earliest primates were contemporaries of dinosaurs. The article is an endorsement for the evolutionary dating system using molecular-clock studies. The earliest primates according to the current fossil record suggests a common ancestor about 55 million years ago after the great dinosaur die-off. Relying on biology and mathematics the new study suggests a small, nocturnal creature of the tropical forests was the earliest primate. The research viewed fewer differences in genetic codes as an indicator that the more recently two species parted evolutionary company, and, math equations were used to flesh out the tree and to predict when and for how long species may have lived. So, really, a Rachel Welch lookalike in a skimpy fur bikini may have actually fled a rampaging T-Rex."
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Earliest Primate Placed With Dinosaurs

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  • duh (Score:3, Funny)

    by tps12 ( 105590 ) on Friday April 19, 2002 @02:01PM (#3375201) Homepage Journal
    Yes, the earliest primates are commonly known as "cavemen," and it is clear that they lived with, ate, and rode dinosaurs for farmwork and warfare. It is a little known fact that monkeys, apes, and even some mammals are also primates, technically related to both humans and cavemen (also known as "early man"). Dinosaurs were either birds or reptiles, or even occaisionally amphibians, but never primates, unfortunately.
    • Re:duh (Score:1, Flamebait)

      by PD ( 9577 )
      That's the most absurd thing anyone's said on this site all day. The primates they are talking about were not "cavemen" and they didn't ride dinosaurs for any reason at all.

      • Re:duh (Score:1, Redundant)

        by PD ( 9577 )
        Someone moderated me flamebait - must be one of those "young earthers".

        I repeat: it's absurd to say that cavemen rode dinosaurs for any reason.
        • Someone moderated me flamebait - must be one of those "young earthers".
          Wasn't this young earther, clearly, since I'm posting here and your score didn't change. Could just be someone looking to start a flamefest perhaps. Since it's a highly unfair mod, you would IMHO be justified to complain about it.
        • You were moderated that way because you completely missed an obvious joke. You made a complete moron of yourself, and therefore you were likely to attract flames. How could you construe that as anything but flamebait?
          • by PD ( 9577 )
            Wow! I already had you marked down as an enemy. Looks like this isn't just a bad day. You're an asshole ALL the time.
            • Whereas this is a unique foray into asshole-dom for you? I'm sorry if you think that my pointing out why you were twice an idiot isn't nice, but you were the one complaining. I was only setting the record straight. I notice that you didn't even bother to try to claim that I wasn't right, because you knew in the depths of your battered soul that I was.

              Don't shoot the messenger, dork.
    • Re:duh (Score:2, Funny)

      These "cavemen" were unearthed from the surrounding "Bedrock", an archeological site scientists described as "a place right out of history."
  • by realgone ( 147744 ) on Friday April 19, 2002 @02:07PM (#3375241)
    Tavaré's team suggested that the earliest primates might have been small, nocturnal creatures...

    A-ha! Coders!

  • No (Score:4, Funny)

    by 4of12 ( 97621 ) on Friday April 19, 2002 @02:10PM (#3375253) Homepage Journal

    So, really, a Rachel Welch lookalike in a skimpy fur bikini may have actually fled a rampaging T-Rex."

    Uh-huh.

    I beg to differ.

    When I saw Planet of the Apes for the first time and saw Raquel Welch in her fur bikini my first thought was NOT

    Recognize Creature = rodent
    DNA match = 0.982
    rather I thought her DNA was spectacularly different from that of myself and most people I knew, and in very important ways.
    • by kippy ( 416183 )
      That was "One Million BC" my friend.

      Planet of the Apes had no shortage of primates.
      • by 4of12 ( 97621 )

        You're right. I stand corrected.

        It was Linda Harrison, not Raquel Welch, that was in the original Planet of the Apes.

  • So, really, a Rachel Welch lookalike in a skimpy fur bikini may have actually fled a rampaging T-Rex."
    The actress' name is Raquel Welch, not Rachel Welch. There's a site here [imdb.com] where you can look up names if you're not sure on the spelling.
    • that seems quite on topic to me... you karma gods suck, let me mod and I'll show you...
      Hay, while your at it, waste your mod points on this too...

  • and, math equations were used

    That's a bit like posting a story on /. saying "computer programming was used in the development of the latest version of the Linux kernel".
  • by ahfoo ( 223186 ) on Friday April 19, 2002 @03:43PM (#3375807) Journal
    The mammal-like reptiles had a skull structure very much like modern mammals and lived not only with the dinosaurs, but hundreds of millions of years before them. These creatures are considered the ancestors of all modern mammals and they would probably have had a facial structure similar to modern mammals given that they had a ridge of bone above the eye sockets where the jaw muscles from their jaw --similar in shape and function to a mammalian jaw, as opposed to a reptilian jaw-- connected to the skull.
    • In fact, during the Permian era mammal-like reptiles made up a significant number of the reptile species. This came to an end after the Permian-Triassic extinction when most of the mammal-like reptiles went extinct.
      Interestingly enough the Permian-Triassic extinction was a much more massive extinction than the extinction at Cretaceous-Tertiary boundry, which killed the dinosaurs off. We have little evidence and are unsure as to what caused the Permian-Triassic extinction.
  • Sorry, no. (Score:3, Funny)

    by juju2112 ( 215107 ) on Friday April 19, 2002 @05:07PM (#3376290)
    So, really, a Rachel Welch lookalike in a skimpy fur bikini may have actually fled a rampaging T-Rex."

    Not unless you think Rachel Welch looks a lot like a Tarsier [simpletone.com]
  • by juju2112 ( 215107 ) on Friday April 19, 2002 @05:33PM (#3376420)
    It sounds like the technique they used was Mitochondrial DNA Concordance [talkorigins.org]

    Mitochondrial DNA is different from nuclear DNA. With the help of mathematics, can be used to determine degrees of relatedness between species, and when two species diverged from their common ancestor. My Human Evolution professor explained this technique in class just yesterday. It was used as evidence that Neanderthals contributed no DNA to the Homo Sapien gene pool.

    Incidentally, talkorgins.org is a great site for this kinda stuff.

    • Another good link related to this:

      http://www.talkorigins.org/faqs/homs/mitoeve.html [talkorigins.org]
    • Do fossils often consist of tissue from which DNA can be extracted? I was under the impression that a fossil would have to be encased in amber,or some other substance that could preserve the integrity of actual tissue in order for dna samples to be extracted. Quicksand or tar pits would preserve the form of the trapped animal, the tar pit would harden and then sedimentation would fill in the space that was left by the completely decayed beast. These become the fossils that we see in museums. Of course when most animals die there is nary a trace of flesh, bone, nor enamel if left to the elements after a short period of time. Its amazing what 75 million years will do to your complexion.
      • mtDNA is different from nuclear DNA. There is a lot more of it per cell, so it's easier to find. It's also shorter - about 16,000 base pairs.

        You're right about how fossils form, that's what I was taught as well. But apparently some DNA can remain if the specimen is not too old. Neanderthals were here just 30,000 years ago. I mean, we're not taking 65 million years here.

        From talk origins:

        After death, DNA starts degrading immediately. It is thought that under the most favorable conditions, some DNA fragments can survive for as long as 50,000 to 100,000 years. The Feldhofer Neandertal fossil, thought to be between 30,000 and 100,000 years old, was therefore pushing the limits for this kind of work. However initial testing of the fossil showed good preservation of amino acids, indicating that it might contain recoverable mtDNA.

        Polymerase Chain Reaction (PCR) is a technique which can be used to create many copies of an initially small number of molecules. The researchers used PCR to amplify and extract many short strands of mtDNA from the Neandertal sample. By overlapping these, they were able to generate a sequence of 379 bases apparently from the Neandertal individual. To protect against errors and contamination, each base was extracted in at least two separate amplifications.


        Also, they can compare mtDNA with a bunch of humans living today, calculate the differences, and then use math to figure out when the common ancestor of all of them lived. So if you want to find out when the common ancestor of two being lived, you don't actually need the mtDNA of the common ancestor.
        • This is definitely not my balliwick but I try to stay current. I thought another very telling trait of mtDNA is that it derives only from the maternal line and was first widely touted as a means to find the _mother_ of us all?

  • This is all based on faith, deep down. Which is the same foundation as believing that God created the world(as He stated in the bible). http://www.geocities.com/lilmacumd/escape.html
  • by Anonymous Coward
    Okay, read this the whole way, please?

    Ever read the book of Genesis in the Bible? It's the first one, the one that says God created the animals, all the animals at the same time. Then He created people who lived at the same time as the dinosaurs and the apes and so forth. Why is this so hard for people to accept? Even if they don't want to believe in God, why is it so far-fetched that people and dinosaurs lived together? Think about this: dragons, sea monsters are in legends and literature world-wide. Hmmm...these could be some of the dinosaurs. We still have "dinosaurs" on the earth: duckbilled platypus, komodo dragon, fringed lizards. How could they have been so large? Read on through Genesis and find the Flood, also in worldwide accounts. Prior to the flood, there existed a cloud layer over a tropical environment. Large plants for large plant-eating animals. Flood wipes out all vegetation and nearly all animals and people except for Noah, his family and 2 of every creature of the air, water, land in a boat. Wait, what about those huge animals? No problem, he took baby dinosaurs which took less space and food. The flood caused tremendous shifting of the earth's land mass causing it to divide and separate. Volcanoes erupted. Then after forty days of rain, the water began to seep into the earth causing great erosions resulting in canyons, a very Grand Canyon even. After the flood, the waters receded, the atmosphere cooled rapidly, an ice age could have occured, the world's environment changed. Large animals no longer had large plant food or other large animals to eat. Process of elimination left us with small dinosaurs.
    THINK ABOUT IT>
    • This is not evidence for HUMANS living with the dinosaurs, only *PRIMATES* Early primates would have resembled something like a lemur.
    • Well there's an awful lot of "could have"'s in there. The problem is that science has proof of so much, whereas religion, as its called, requires faith. Not to say that faith makes it untrue.

      I wonder though... those that don't believe in Jesus, and practice drastically different religions.. to "us," they are going to hell. To them, what if we are going to their equivelant of hell FOR believing in Jesus? (I'm not saying we ALL do, I'm just speaking generally here.)

      Chinese people don't believe in Jesus or "God." Are they going to hell? And if so, does that mean that, here on earth, they represent satan and we should either convert or destroy them? I like the Chinese people I know.

      In the end, my point is that science and religion don't always mix. But they just might one day... because remember one thing:

      Science and religion are exact opposites in the aspect that religion is pre-defined, whereas science started at 0 and has progressed through time. In the end, they just might meet up... I know when I look up into the sky and the stars, I have a much better sense of "heaven" that pure science OR pure religion can prove to me with texts and theories and accounts. It's just THERE... those stars. And for me, that's where science+religion make perfect sense and symmetry.
    • Actually, This seems closer to the truth (the Gospel according to Tony Hendra) The Book of Creation [freethought.org]

      It's a pity the book's out of print. It's very insightful and makes just as much sense as the bible.
      Yes, I know this is going to get labeled a troll,
      but SOMEONE has to say it.... :)

      Saint Eyegor (Patron Saint of the Church of Steve).
    • Why is this so hard for people to accept?

      Because there is exactly zero evidence for it (and plenty that just plain contradicts it). If you want to accept it on faith, that fine by me. Personally I prefer the scientific method, but it's just a case of different courses for different horses.
  • by the phantom ( 107624 ) on Saturday April 20, 2002 @09:57AM (#3379144) Homepage
    First off, this is probably the knee-jerk reaction in defense of everything that I have been taught (ala Kuhn's The Structure of Scientific Revolution -- old guard fights to defend their theories while those damn punk children walk all over them -- funny that, I should be one o' those punk kids!) however, without seeing a technical article explaining how these conclusions were reached, I have a couple of questions:

    How did they arrive at this date of 81.5 million years ago? They discuss using DNA and mathematical estimates of age. Both are highly theoretical, and I could run the same experiment, using only slightly different numbers and come up with something completely different. In the case of DNA (probably Mitochondrial DNA, not nuclear DNA), we do not know the rate of genetic drift -- it is variable for all we know. So, assumptions based on MtDNA are on tenuious ground. In the case of their equations, what were these equations? What were the base assuptions used to create them?

    It is interesting to think that primates have evolved much earlier than the fossil record indicates, but it is very hard to believe without any real evidence. As the article itself states "'Of course, this is all speculation,' Tavaré acknowledged. 'We have not found any fossils in that bin yet.'"
    • I think it is healthy to demand proper evidence for all scientific claims! And I am quite certain the the authors, Tavare in particular given your own quote, are well aware of this and do not see their conclusions as written in stone. Also, it is interesting to notice that the authors are probably from what you call the "old guard". I know Tavare is, and his co-authors being spread all over the world in distinguished departments suggests the same for them.

      As to their method, please see my other post [slashdot.org]. It is certainly public, and it will be scrutinized by other researchers for sure. You can visit your closest research library and look it up in Nature. In short, they do not use DNA for their analysis, only the fossil record.

      Cheers,

  • by juju2112 ( 215107 ) on Saturday April 20, 2002 @12:48PM (#3379737)
    The Field Museum in Chicago, where this study was done, has an nice press release on this here [fieldmuseum.org].

    They also released a sketch [fmnh.org] of what the earliest common ancestor for primates might have looked like, and a nice evolutionary tree [fmnh.org] which might put some of this into perspective for some of you.

  • According to some scholars, we all descend from Ron Perlman [imdb.com].

    RMN
    ~~~
  • I have browsed the Nature paper by Tavare et al [nature.com] that is the basis for the National Geographic piece, and have a good idea about what they are actually doing.

    Contrary to what people here at /. are expecting, the authors do not use molecular data in their method (although they have compared their findings with studies using DNA). Instead, they have used a model for how species appears and goes extinct, modelled how the fossil record has been sampled, and then compared with known fossil data.

    The speciation/extinction model says that species go extinct and split up in subspecies at certain rates. The fossil findings model is simply that the number of found fossils from a certain period of time is binomially distributed.

    Data summarizing the number of primate fossils from different time periods was collected, and a starting point for the primate lineage that best explained the fossil record was computed.

    In essence, if the starting point is too early, the method disqualifies it because we have not seen enough fossils, and if it is too late, it is disqualified because we have seen too many.

    I could add that Simon Tavare is a well-respected statistician with solid experience in, for example, population genetics. (I don't recognize the other author names.) It would have been nice to see comments from other researchers about their assumptions, but I did not see anything on the Nature site and have not had the time to research this more closely.

    Cheers,

The most difficult thing in the world is to know how to do a thing and to watch someone else doing it wrong, without commenting. -- T.H. White

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