River Out of Eden

February 27, 1995
Dawkins (The Selfish Gene) pictures evolution as a vast river of DNA-coded information flowing over millennia and splitting into three billion branches, of which 30 million branches--today's extant species--survive. Emphasizing that the genetic code is uncannily computer-like, comprising long strings of digital information, the eminent Oxford evolutionary biologist surmises that we are ``survival machines'' programmed to propagate the database we carry. From his perspective, nature is not cruel--only indifferent--and the goal of a presumed Divine Engineer is maximizing DNA survival. Dawkins cautiously endorses the controversial ``African Eve'' theory, according to which the most recent common ancestor of all modern humans probably lived in Africa fewer than 250,000 years ago. The author's narrative masterfully deals with controversies in evolutionary biology. Natural Science Book Club dual main selection; Library of Science alternate.