Cooperative Gene

The Cooperative Gene is about sex and how sex enabled complex life to arise. Mark Ridley, a researcher and author of many works including the textbook Evolution, contends that simple life is "easy." Simple life like bacteria evolved as soon as conditions on Earth permitted. But complex life--walking, flying, swimming, squawking organisms with differentiated tissues--was a huge step forward. It took billions of years for complex life (and sex) to appear.

More than anything, organisms want to pass on their genes. Sex seems to defy natural selection in its ability to convince organisms to pass on only half their genes. Natural selection will favor "selfish" genes, ones that can beat the odds and get passed on. But if this happened all the time, complex life could not exist. So how does it? Enter what Ridley describes as "Mendel's demon," a system in which genes are passed on in a random fashion. Most important, the demon prevents selfish genes from sabotaging that randomness.

Although Gene isn't a technical book, its ideas are complicated. Ridley's style is methodical, broken by the occasional dryly humorous aside. Evolutionary biologists and other assorted PhDs will no doubt be entertained. Popular-science buffs may find it slow going, but they will be rewarded by a thorough understanding of the topic.

In his last two chapters, Ridley leaps further afield, exploring the influence of technology on human evolution and speculating how future science could change us. He also examines the idea of supercomplex organisms, beings that would tower over humans in complexity to the same degree that humans tower over bacteria. It's pure speculation but compelling nonetheless, worthy of its own book. --J. B. Peck