> Recent research using DNA analysis answered this question about two years ago. Today’s human population is descended from twice as many women as men.
Initial studies, such as Thomson et al. 2000[7] proposed that Y-chromosome Adam lived about 59,000 years ago. This date suggested that Y chromosome Adam lived tens of thousands of years after his female counterpart Mitochondrial Eve, who lived 150,000-200,000 years ago[8]. This date also meant that Y-chromosome Adam lived at a time very close to, and possibly after, the out of Africa migration which is believed to have taken place 50,000-80,000 years ago.
One explanation given for this discrepancy in the dates of Adam and Eve was that females have a better chance of reproducing than males due to the practice of polygyny. When a male individual has several wives, he has effectively prevented other males in the community from reproducing and passing on their y-chromosomes to subsequent generations. On the other hand, polygyny doesn't prevent most females in a community from passing on their mitochondrial DNA to subsequent generations. This differential reproductive success of males and females can lead to fewer male lineages relative to female lineages persisting into the future. These fewer male lineages are more sensitive to drift and would most likely coalesce on a more recent common ancestor. This would potentially explain the more recent dates associated with Y-chromosome Adam.[9][10]
Does anyone know what research he's referring to?