It seems that when it had to pick the species that would dominate the animal reign a few million years ago, nature flipped a coin. The choice was between humans and chimps.
Scientists at the Georgia Institute of Technology have found genetic evidence that seems to support a controversial hypothesis that humans and chimpanzees may be more closely related to each other than chimps are to the other two species of great apes, gorillas and orangutans. In addition, the team led by biologist Soojin Yi says that
the rate of human and chimp molecular evolution, in other words, the changes that occur over time at genetic level, are much slower than that of gorillas and orangutans.
"For the first time, we've shown that the difference in the rate of molecular evolution between humans and chimpanzees is very small, but significant, suggesting that the evolution of human-specific life history traits is very recent," said Yi.
Most biologists believe that humans and chimpanzees had a common ancestor before the evolutionary lines diverged about 5-7 million years ago.
According to the analysis, one million years ago, the molecular clock in the line that became modern humans began to slow down. Today, the human molecular clock is only 3 percent slower than the molecular clock of the chimp, while it has slowed down 11 percent from the gorilla's molecular clock.
This slow down in the molecular clock correlates with a longer generation time
"A long generation time is an important trait that separates humans from their evolutionary relatives," said Navin Elango, first author of the research paper.
The results also confirm that there is very little difference in the alignable regions of the human and chimp genomes, and that the two species are closely related.
Find us on Google+
