“…the Y chromosome Adam could have lived any time between 120,000 and 160,000 years ago, while “mitochondrial Eve” could have lived any time between 99,000 and 148,000 years ago.”
“But there’s a bigger problem. As I note in the Albatross, “although all the Y chromosomes of modern humans descend from this one individual, the rest of our genome descends from a multitude of different ancestors who lived at various times ranging from 100,000 to about 4 million years ago.
Our genome testifies to literally hundreds of ‘Adams and Eves’ who lived at different times—a result of the fact that different parts of our DNA were inherited differently based on the vagaries of reproduction and the random division of genes at when sperm and eggs are formed.” It’s not just mitochondrial and Y-chromosomal DNA we have to consider, but the entire human genome. And that shows clearly that parts of the genome go way back before the DNA on the Y and on the mitochondrion.
Indeed, parts of our genome originated even before our divergence from the ancestors of chimps! We have some variable genes, for example, with variants that are more closely related to gene forms in chimps than to other genes in humans. That shows that the variability was hanging around in our common ancestor, and that the variability has persisted over more than five million years.”