Darwin thought life evolved like a tree growing, with a single common trunk opening out into a myriad of branches and twigs. But today, says Prof. Ford Doolittle of Dalhousie University, Nova Scotia, at the forefront of fundamental research in evolutionary biology for over four decades, it’s clear the situation is more complex.
“For bacteria it may be more appropriate to speak of the Web of Life, because there is rampant exchange of genes across species lines. This web-like evolution is a challenge to neo-Darwinism, and a source of controversy within the discipline and in the public arena.”
He sets out his ideas in conversation.