A new study in the journal Investigative Genetics shows that, throughout human history, more women were reproducing than men were.
The study examined DNA samples of people from around the world, looking into their mitochondria DNA (mtDNA) passed down through the female line and at the y-chromosone passed down through the male line.
The researchers found that historically, more women than men were reproducing, potentially as a result of polygyny (in which one man is married to multiple wives). But the results also showed geographical differences, as LiveScience reports:
On a regional scale, the DNA samples showed a detailed story. For example, people in East Asia and Europe have larger genetic differences for paternal than for maternal DNA, suggesting high levels of female migration. In contrast, populations in Africa, Oceania and the Americas have bigger differences for maternal DNA than for paternal DNA.
Perhaps fewer men than women reproduced among America's early colonists, the researchers said when they saw the high amount of mitochondrial DNA diversity.
Mitochondrial DNA is useful for all sorts of historical explorations; it has also, recently, been one of the key components in the identification of Richard III, whose body was found buried in a parking lot in 2012., and in the newest evidence for the real identity of Jack the Ripper.