Homo Sapien vs. Chimpanzee - Divergence Timeline


by Murdstone
Tags: chimpanzee, divergence, homo, sapien, timeline
Murdstone
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#1
Feb9-12, 12:20 AM
P: 32
What is wrong with this logic?

Homo Sapien

1. 46 (diploid) chromosomes
2. 32,185 genes
3. 3,079,843,747 bases (DNA bases A,C,T,G)
4. Homo sapines diverged from chimpanzees 6 million years ago.
5. There is a 3% difference in the genetic makeup of a homo sapien and a chimpanzee.
6. 3,079,843,747 x .03 = 615,968 (number of different bases, in the correct order, that would have to manifest via random mutation and natural selection for homo sapiens to be different from chimpanzees.)

The first error is that 3,079,843,747 x .03 = 923,953

So we have 923,953 different base pairs, in the correct order, that would have to manifest via random mutation and natural selection in only 6 million years.
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SW VandeCarr
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#2
Feb9-12, 01:22 AM
P: 2,490
Quote Quote by Murdstone View Post
What is wrong with this logic?


4. Homo sapines diverged from chimpanzees 6 million years ago.
Really? What's the evidence for that? Chimpanzees and humans have a common ancestor. The earliest known ancestor in the human line is thought to be Austalopithecus followed by H. habilis, H.erectus/ergaster and then H. sapiens.
Ken Natton
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#3
Feb9-12, 01:44 AM
P: 272
As ever with posts like yours, Murdstone, the strong suspicion has to be that you have a prior agenda and don't really want to listen to the rational, logical, scientific answers to your objection. If you really do want to understand, then my strong recommendation to you is to read a couple of books by a guy called Sean Carroll. He is a front line researcher and writes wonderfully accessible books. The two you need to look for are called 'Endless Forms Most Beautiful' and 'The Making of the Fittest'. In those books, Carroll deals excellently with the whole misunderstanding of what a gene is and what a gene does that leads to a better understanding of why the Human and Chimpanzee gernomes are so similar and yet the morphologies of those two species are so different.

bobze
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#4
Feb9-12, 02:23 AM
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Homo Sapien vs. Chimpanzee - Divergence Timeline


Quote Quote by Murdstone View Post
What is wrong with this logic?

Homo Sapien

1. 46 (diploid) chromosomes
2. 32,185 genes
3. 3,079,843,747 bases (DNA bases A,C,T,G)
4. Homo sapines diverged from chimpanzees 6 million years ago.
5. There is a 3% difference in the genetic makeup of a homo sapien and a chimpanzee.
6. 3,079,843,747 x .03 = 615,968 (number of different bases, in the correct order, that would have to manifest via random mutation and natural selection for homo sapiens to be different from chimpanzees.)

The first error is that 3,079,843,747 x .03 = 923,953

So we have 923,953 different base pairs, in the correct order, that would have to manifest via random mutation and natural selection in only 6 million years.

3 things; first, can you clarify what your question is?

Second: don't forget that humans and chimpanzees share a common ancestor. We didn't evolve from them, so its not as if their genome has remained static this past 5-6 million years either. We've both been evolving from the last common ancestor for equal amounts of time.

Third: the "degree" of similarity between humans and chimpanzees depends upon the "resolution" we are viewing the genome through. Are we talking coding genes? Chromosome homology? Genomes? Etc.
Ryan_m_b
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#5
Feb9-12, 03:33 AM
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Quote Quote by bobze View Post
Second: don't forget that humans and chimpanzees share a common ancestor. We didn't evolve from them, so its not as if their genome has remained static this past 5-6 million years either. We've both been evolving from the last common ancestor for equal amounts of time.
Precisely!
Quote Quote by bobze View Post
Third: the "degree" of similarity between humans and chimpanzees depends upon the "resolution" we are viewing the genome through. Are we talking coding genes? Chromosome homology? Genomes? Etc.
Despite our over 98% similarity to the chimp genome our proteome shares only ~80% similarity as those genomic differences are amplified by slightly different alternative splicing, polyadenylation, post-transcriptional modification, post-translational modification etc.
Quote Quote by Murdstone View Post
Homo sapines diverged from chimpanzees 6 million years ago
Homo sapiens are only 200,000 years old. The homo genus is only ~2.5 million years old. A variety of different genus and species have evolved since we last shared a common ancestor with chimps.
Quote Quote by Murdstone View Post
So we have 923,953 different base pairs, in the correct order, that would have to manifest via random mutation and natural selection in only 6 million years.
That number isn't as ridiculous as you seem to be implying. Taking a generation as 20 years then 6,000,000/20 = 300,000 generations. This amounts to roughly 3 mutations per generation or 1.5 mutations in the human side of the divergence and 1.5 in the chimp side. That's not unreasonable at all and actually far less than some estimates.


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