Looks like we’re all related whether you like it or not. That’s good news: I need help painting my house next weekend.
In work made public today in the journal Science, the team of prominent biologists corroborates the idea that modern humanity originated around 200,000 to 300,000 years ago, rather than a million years earlier, as other experts have theorized.
“It suggests we really are an extremely recent species on this planet,” said Yale University biologist Robert L. Dorit, who led the group. “We are definitely rookies . . . noisy, but new.”
The new research also provides additional evidence that modern humans–despite their apparent racial and ethnic differences–all share the same basic genetic makeup. In one section of the chromosome that makes a person male, men around the world are virtually identical, the scientists discovered.
For their analysis, they sequenced a portion of the male sex chromosome that apparently changes quite slowly over the eons. To ensure that their sample would encompass the range of human geographic diversity, they used chromosomes from 38 men chosen from every continent. They discovered virtually no differences, despite the fact that genetic mutations usually occur at a predictable rate.
“Originally we were terribly surprised by the lack of variation,” said Harvard University biologist Walter Gilbert, a Nobel laureate who worked on the study. “We realized very early that meant a recent common male ancestor.”
Hat Tip: J.R. Thanks!