Why sex? Why then only two sexes? Why do we age and die?

Peter Forbes in The Guardian:

MitoThe “Origin of Life” is a conundrum that could once be safely consigned to wistful armchair musing – we’ll never know so don’t take it too seriously. You will probably imagine that it’s still safe to leave the subject in this speculative limbo, without very much in the way of evidence. You’d be very wrong, because in the last 20 years, and especially the last decade, a powerful new body of evidence has emerged from genomics, geology, biochemistry and molecular biology. Here is the book that presents all this hard evidence and tightly interlocking theory to a wider audience. While most researchers have been bedazzled by DNA into focusing on how such replicating molecules have evolved, Nick Lane’s answer could be characterised as “it’s the energy, stupid”. Of all the definitions of life, the one that matters most concerns energy: the churn of metabolic chemistry in the cells and the constant intake of nutrients and expulsion of waste are the essence of life. Information without energy is useless (pull the plug on your computer); information could not have started the whole thing off but energy could.

It is widely recognised that the creation of a viable primitive living cell, capable of reproduction and Darwinian selection, has three requirements: a containing membrane, which acts as an interface between the organism and the environment; replicators able to store the genetic instructions for the organism and to synthesise its chemical apparatus; and a way of taking energy from the environment and putting it to work to run the cell’s processes. Lane shows how all the rest can follow if we put energy first. He is a researcher in evolutionary biochemistry at University College London who has been developing his grand energy theory of life, the universe and everything for more than two decades, explaining it in the books Oxygen (2002), Power, Sex, Suicide(2005) and Life Ascending (2009), which won the Royal Society book prize in 2010. He is an original researcher and thinker and a passionate and stylish populariser. His theories are ingenious, breathtaking in scope, and challenging in every sense. To read him, it helps, as Richard Dawkins once said of himself when embarking on an intricate passage in The Blind Watchmaker, to bring your “mental running shoes”.

More here.