Ancient chimpanzee Adam lived over one million years ago

Chimpanzees have an ancient common ancestor – or genetic ‘Adam’ - that lived over one million years ago, according to a research team led by Professor Mark Jobling from the Department of Genetics.

In a study, which was funded by the Wellcome Trust and published in the journal Genome Research, the research team determined the DNA sequences of a large part of the Y chromosome, passed exclusively from fathers to sons, in a set of chimpanzees, bonobos, gorillas and orangutans.

The study also looked at mitochondrial DNA (mtDNA), passed from mothers to offspring, in the same set of animals.

This allowed the construction of genealogical trees that could be compared between species and subspecies – and helped the researchers to discover that the genetic ‘Adam’ for chimpanzees lived a remarkable one million years ago.

Dr Pille Hallast from the Department of Genetics, lead author on the paper, explained: “The ancestor of a Y-chromosome family tree is sometimes called ‘Y-chromosomal Adam’. We can compare the ages of ‘Adams’ between the species. For humans the age is about 200 thousand years, while for gorillas it’s only about 100 thousand years. Thanks to two chimps in our sample, Tommy and Moritz, chimpanzees have an amazingly ancient ‘Adam’, who lived over 1 million years ago.

“The Y chromosome tree for gorillas is very shallow, which fits with the idea that very few male gorillas (alpha males) father the offspring within groups. By contrast, the trees in chimpanzees and bonobos are very deep, which fits with the idea that males and females mate with each other more indiscriminately.”