River Out of Eden

Reviewed by Bernard Howard

We start by setting this book into its two contexts. In the publishing context it is the fourth in the “Science Masters” series; authors of its predecessors are two cosmologists (J. D. Barrow and Paul Davies) and an anthropologist (Richard Leakey), and successors are promised from an equally glittering list of science writers.

In the “Dawkins context” this book continues the argument started in The Selfish Gene and The Blind Watchmaker. Readers familiar with these will find the same highly readable style, vivid prose and vigorous argument.

The title is from the Book of Genesis: “And a river went out of Eden to water the garden”. That one of the most scornful critics of those who believe in the literal truth of the Biblical creation myth uses this source should raise a smile for its cheekiness.

The extraordinary variety of life today results from the appearance on Earth more than 3000 million years ago of self-replicating chemical units. The flow through time of these units and their successors, the genes we know today, making use of mortal bodies on the way, Dawkins likens to the flow of water down an ever-broadening and dividing river. He makes much of the fact that this is a flow of information, and like the information in the better quality electronic communications, it is digitised.

A chapter is given to “African Eve”, possible ancestor in the female line to all us humans today, and, the author claims, a much more interesting person than her Biblical namesake. Other chapters are on gradualism (evolution of eyes and other marvellous mechanisms) and on “God’s Utility Function”, in which the “problems” of evil and suffering are brusquely dismissed.

In his final chapter, Dawkins speculates on the universal aspects of evolution — what are the essential elements of the process, wherever it may occur? He defines several thresholds which must be crossed as the complexity of replicating systems increases. We have recently crossed the ninth, or Radio Threshold, where the escape of radio signals from Earth could alert distant observers, for the first time, to the occurrence of life here. We are on the verge of his 10th and final threshold, that of space travel.

T.H. Huxley, the 19th-century champion of evolution by natural selection, was nicknamed “Darwin’s Bulldog”. Recently the “Scientific American” referred to E. Mayr, the eminent nonagenarian biologist, as “Darwin’s Current Bulldog”. In the kennels of evolutionary theory, we may regard Dawkins as “Darwin’s Rottweiler”, for his aggressive defence of, and wide claims for, natural selection.

A footnote: has Dawkins been taken over by his American spell-checker? Despite the book’s English origins, any words with alternative spellings are in American English.