N.Wells
Posts: 1836
Joined: Oct. 2005
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Prufer et al., 28 June 2012, The bonobo genome compared with the chimpanzee and human genomes
Nature, 486: 527–531.
http://www.nature.com/nature.....28.html
Their Figure 2 is very interesting:
http://www.nature.com/nature.....F2.html
That diagram shows that by one particular measure, humans are genetically very similar to both P. paniscus and P. troglodytes, and are about equally distant from both, and that P.p. and P.t. are extremely similar to each other.
Their Figure 3
http://www.nature.com/nature.....F3.html
infers a separation time between the human and Pan lineages at 4.5 m.y. and a separation between Pan troglodytes and Pan paniscus at about 1 m.y. ago.
| Quote | | comparison of a small number of autosomal DNA sequences has shown that bonobo DNA sequences often fall within the variation of chimpanzees. |
| Quote | | On average, the two alleles in single-copy, autosomal regions in the Ulindi [bonobo] genome are approximately 99.9% identical to each other, 99.6% identical to corresponding sequences in the chimpanzee genome and 98.7% identical to corresponding sequences in the human genome. |
So bonobos are very close to common chimps and less close to modern humans.
Beyond that, there are interesting complications. A small % of the human genome is more similar to common chimps than to bonobos, and a nearly identical small % is more similar to bonobos than to common chimps:
| Quote | This showed that 1.6% of the human genome is more closely related to the bonobo genome than to the chimpanzee genome, and that 1.7% of the human genome is more closely related to the chimpanzee than to the bonobo genome .....
.......
We identified 991 integrations of transposons absent from the orang-utan genome but present in two of the three species bonobo, chimpanzee and human. Of these, 27 are shared between the bonobo and human genomes but are absent from the chimpanzee genome, and 30 are shared between the chimpanzee and human genomes but are absent from the bonobo genome.......
We identified 18 such amino-acid substitutions shared between humans and bonobos and 18 shared between chimpanzees and humans |
How Science sums up the Prufer study:
http://www.sciencemag.org/news....latives
| Quote | | When the Max Planck scientists compared the bonobo genome directly with that of chimps and humans, however, they found that a small bit of our DNA, about 1.6%, is shared with only the bonobo, but not chimpanzees. And we share about the same amount of our DNA with only chimps, but not bonobos. These differences suggest that the ancestral population of apes that gave rise to humans, chimps, and bonobos was quite large and diverse genetically—numbering about 27,000 breeding individuals. Once the ancestors of humans split from the ancestor of bonobos and chimps more than 4 million years ago, the common ancestor of bonobos and chimps retained this diversity until their population completely split into two groups 1 million years ago. The groups that evolved into bonobos, chimps, and humans all retained slightly different subsets of this ancestral population's diverse gene pool—and those differences now offer clues today to the size and range of diversity in that ancestral group. |
From Scientific American, 2014
https://www.scientificamerican.com/article....-genome
| Quote | | chimps and bonobos in particular take pride of place as our nearest living relatives, sharing approximately 99 percent of our DNA, with gorillas trailing at 98 percent. |
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