Under The Microscope

CLIMBING MOUNT IMPROBABLE by Richard Dawkins; Viking/Penguin Books, 1996; xi + 308 pps; $49.95 (hardcover)

That master of the telling metaphor, the man who gave us The Selfish Gene and The Blind Watchmaker, is at it again! This time the metaphor is evolution as mountaineering.

Imagine you are standing on the abiotic plain, surrounded by "dull" inorganic matter. Before you, though, rises an immense range of mountains, with millions of fantastic peaks representing all the forms of life. They present forbidding faces to you, of high, unscalable cliffs.

How to lift yourself from the plain to those wonderful biological heights? Impossible, you say. "Not so", replies Dawkins, "merely improbable. Forget the cliffs; at the back of the mountains are gently sloping paths that will take you to the topmost peaks. Let me be your guide, and obey only three rules:- give yourself plenty of time (a few billion years), take very small steps and never go downhill".

This book surveys some of the routes and peaks on the improbable mountain. A chapter each is given to detailed accounts of the ascent of two mountains guarded by particularly high cliffs -- the peaks labelled "wings" and "eyes". At the foot of the latter, especially, we encounter groups of creationists chanting "Mount Impossible!", but, following guide Dawkins we find the track surprisingly easy, and we ascend quickly.

Readers familiar with the author's evolutionary computer program "Blind Watchmaker" will appreciate the advances offered by "Netspinner". This program traces possible evolutionary pathways for spiders' webs, allowing "natural selection" to direct change, balancing efficiency at "catching flies" against costs of building the "web". Other chapters describe the 3-D space of all possible shells, and the types of biological symmetry, and discuss what things, for example flowers, are "for".

In the author's 1995 book, River Out Of Eden, we were given a taste of Lalla Ward Dawkins's artistic skill. The present, much more copiously illustrated, book is embellished by almost 40 of her meticulously executed, beautiful drawings of plants and animals.

In his introduction, Dawkins offers this advice to popularisers of science: "Do not talk down. Try to inspire everybody with the poetry of science and make your explanations as easy as honesty allows, but...do not neglect the difficult."

How does this book meet its author's criteria? "Talking down"? not a trace; "inspiration", "poetry of science"? heaps on every page; "explanations"? brilliant clarity; "do not neglect the difficult"? try the final chapter on figs and their wasps, "atop one of the highest peaks of Mount Improbable".

Having read Dawkins' previous books, I picked up this one with misgivings, wondering if he had anything new to say about life and its origin. How wrong I was!

Bernard Howard is an Emeritus Professor of Soil Science from Lincoln University.