THE ANCESTOR’S TALE

Borrowing from Chaucer, Dawkins leads a grand tour of all surviving “pilgrims” to a “Canterbury” representing the very origin of life—and what a fantastic trip it is.

It’s Dawkins (Science/Oxford; A Devil’s Chaplain, 2003, etc.) the consummate zoologist on display here, marching us humans backwards in evolutionary time to 40 Rendezvous to meet our “concestors,” the proposed common ancestor we share at each successive stage of our evolutionary history with other survivors. Thus the concestor of humans and chimpanzees is encountered at Rendezvous 1, around 6 million years ago; by Rendezvous 9 (70 million years ago), human, ape, and monkey pilgrims are joined by the tree shrews to conjecture what that concestor looked like, and on through all animals—fungi, plants, etc.—to the final stages of Archaea (exemplified by those heat-lovers from deep ocean vents) and bacteria. The exercise allows Dawkins to elaborate on weather, geology, and geography, on catastrophic events, and on numerous evolutionary concepts, like convergence (independent adaptations for flight or sight, for example). The panorama is splendid, but it’s the details, often included in the animal “pilgrim” tales told at each rendezvous, that delight, and also exhibit some of Dawkins’s best writing. We learn that 40 percent of all mammal species are rodents; that hippos are closer to whales than pigs; that aye-ayes have fingers like an Arthur Rackham witch; and that, among all creatures, it is bacteria that invented the wheel. To be sure, Dawkins does not spare creationists here. He also lectures on racism, and includes some Bush and Blair bashing for good measure. The author is also quite upfront about degrees of uncertainty (the further back in time we go), the current speculative theories on origins he favors, and why he feels that running the evolutionary clock forward might not be a crapshoot (as the late Stephen Jay Gould thought) but would show a form of progress/complexity and even “the evolution of evolvability.”

One of Dawkins’s best: a big, almost encyclopedic compendium bursting with information and ideas.