THE TANGLED TREE

Nonpareil science writer David Quammen explains how recent discoveries in molecular biology can change our understanding of evolutio n and lifes history, with powerful implications for human health and even our own human nature. In the mid-1970s, scientists began using DNA sequences to reexamine the history of all life. Perhaps the most startling discovery to come out of this new fieldthe stu dy of lifes diversity and relatedness at the molecular levelis horizontal gene transfer (HGT), or the movement of genes across spe cies lines. I...[Read more]