PARIS: The bonobo genome, the last genome of the apes to be read, has revealed 3% similarity with humans, and some DNA encryption more in common with humans than even its closest relative, the chimpanzee.
The bonobo is the last of the so-called great apes to have its genome sequenced, after those of chimpanzees, gorillas and orangutans.
The data, which scientists hope will shed more light on the lineage of humans, was obtained from Ulindi, a female bonobo at Leipzig zoo.
It showed that more than 3% of the human genome, which contains our hereditary data encoded in DNA, was more closely related to either the bonobo or the chimpanzee genome than these were to each other.
Humans differ by 1.3% from chimps and bonobos
The information "opens the possibility of gauging the genetic diversity and, hence, the population history of the (common) ancestor," said the international research team of the study published in the journal Nature.
The bonobo and the chimp are our closest living relatives.
The genomic study showed that humans differed by about 1.3% from the bonobo or the chimpanzee, who in turn differed by about 0.4% from each other.
Although they are similar in many respects, the two African apes differ in key social and sexual behaviour, and in some show more similarity with humans than with each other.
Male chimps aggressively compete for dominance and sex, and join forces to defend their home range and attack other groups.
Sex for fun
Bonobo males, however, are commonly subordinate to females, do not compete for rank and do not partake in battle. They are playful animals who have sex for fun, not just to reproduce.
"Chimpanzees and bonobos each possess certain characteristics that are more similar to human traits than they are to one another's," said the research paper.
This showed that a common ancestor "may in fact have possessed a mosaic of features, including those now seen in bonobo, chimpanzee and human".
Chimpanzees are widespread across equatorial Africa, while bonobos live only south of the Congo River in the Democratic Republic of Congo.
Because of their small and remote habitat, bonobos were the last ape species to be 『discovered』, in the 1920s, and are the rarest of all apes in captivity.
Scientists are as yet unable to use the genome to determine what the DNA donor would look like or how they would behave.
Hope to find common ancestor
Researcher Kay Pruefer, a biologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said the research provided more information on bonobos and chimpanzees than it did about humans.
"But at some point, our hope is that understanding the differences between bonobos and chimpanzees … will help us also understand what the common ancestor (of humans, chimps and bonobos) looked like," he said.
"This would actually start being very interesting for us because it would inform us what was actually a new trait that humans acquired in their evolution over the last millions of years."
The researchers said the gene sequencing showed that bonobos and chimps did not mix or interbreed after their paths split geographically about two million years ago, possibly by the formation of the Congo River. |
發表於 2012-7-14 08:45:22