© Ian BickerstaffResearchers have sequenced the first full set of great ape genomes. Shown here: chimpanzees and gorillas.
The most comprehensive catalog of great-ape genome diversity to date offers insight into primate evolution, revealing chimpanzees have a much more complex genetic history than humans.
In a new study, researchers sequenced a total of 79 great apes, including chimpanzees,
bonobos, eastern and western gorillas,
orangutans and humans, as well as seven ape subspecies. The animals were wild- and captive-born individuals from populations in Africa and Southeast Asia.
Much attention has been focused on studying the diversity among human genomes, said study researcher Tomas Marques-Bonet, a geneticist at the Institut de Biologia Evolutiva in Spain. "If we want to understand the genetic diversity of humans, we need to measure the genetic diversity of our nearest relatives," Marques-Bonet said.
As part of the study, Marques-Bonet and his colleagues were looking for genetic markers corresponding to changes in a single letter in the genetic code that define a subspecies. The researchers identified millions of such markers, which are important for conservation efforts.
For instance, these markers allow people who manage wild-ape populations to identify different kinds of ape. Most of these animals are captured from illegal trade, so scientists don't know how they're related, Marques-Bonet told LiveScience.
Surprisingly, Marques-Bonet said, the genetic history of chimpanzees turned out to be much more complex than that of humans. Compared with chimps, "it looks like our [humans'] history has been really simple," Marques-Bonet said. Human populations encountered a bottleneck when they left Africa, and have since expanded to colonize the whole planet. By contrast, chimpanzee populations have undergone at least two to three bottlenecks and expansions, Marques-Bonet said.