Chimps and Bonobos- Susanna Israelsson

“Chimps and Bonobos had a Fling in the Past”

Susanna Israelsson 11/14

http://science.sciencemag.org/content/354/6311/477.full
http://www.aaas.org/news/chimps-and-bonobos-had-fling-past

Chimps and bonobos are sister taxa of the genus pan.  They share 99.6% of their genomes, and they split over two million years ago.  While bonobos and chimps have interbred in captivity, this is an unnatural setting and there have been no observations of interbreeding in the wild.  Researchers were inspired by the work Svante Paabo and his team have done with Neanderthal and modern human genomes.  They were curious to see if similar evidence of interbreeding existed in the Pan sister taxa.  They collected DNA and successfully sequenced the genomes of 75 wild apes; 10 bonobos and 65 chimps.

After comparing the genomes, researchers determined that archaic chimpanzees and bonobos interbred 200,000 to 550,000 years ago.  In particular, bonobos mainly bred with central and eastern chimpanzees, which is probably due to geography.  This geography-specific interbreeding is similar to how Neanderthal DNA is present in European and Asian individuals, but not as much in African individuals.  The researchers do theorize that the interbreeding may not have been advantageous for chimpanzees, but more work is required to determine if this is accurate, and why.  

Chimp
Pan troglodytes

Bonobo
Pan paniscus