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Earliest Primate Placed With Dinosaurs
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."
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.
Karma: Good (despite my invention of the Karma: sig)
A-ha! Coders!
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
rather I thought her DNA was spectacularly different from that of myself and most people I knew, and in very important ways."Provided by the management for your protection."
That's a bit like posting a story on
-- SIGFPE
Offtopic I know but...
Slap me silly and call me T-Rex. I want to eat Rachel Welch too!
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.
Not unless you think Rachel Welch looks a lot like a Tarsier
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.
Impersonating Tycho from Penny Arcade since before there was a PA.
It sounds like the technique they used was Mitochondrial DNA Concordance
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.
She does look kinda cute, too short for my tastes though
Deep down this is still based on faith. Same foundation as a God created world(as He has said in the Bible)
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
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>
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.'"
Rhapsody in Numbers
The Field Museum in Chicago, where this study was done, has an nice press release on this here.
They also released a sketch of what the earliest common ancestor for primates might have looked like, and a nice evolutionary tree which might put some of this into perspective for some of you.
According to some scholars, we all descend from Ron Perlman.
RMN
~~~
We need more science articles. Why not just let a few rejected ones go on the science section page? It won't cost you much.
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,
Reality or nothing.