Return to main Mensa page


"Ever Since Darwin" by Stephen Jay Gould

A Book review by Matthew Shepard


This book contains a series of essays on the theme of "reflections in natural history"; it is an exciting book, extremely well written, and will undoubtedly confound anyone who imagines that natural history is not much more than numbering, listing and cataloguing. On the contrary, Stephen J Gould demonstrates how evolutionary theory can unify and make sense of masses of disparate data.

I found one of the essays particularly fascinating because it shows how blind intellectuals - even scientists - can be to their own prejudices, and how uncritical speculation, in the absence of evidence, tends to follow the guidelines laid down by prejudice, and not portray what it fondly imagines to be "objectivity".

Consider the problem: how did man come to walk upright? In the traditional view, he learnt to walk upright just as a child develops from crawling to learning to walk; in this scenario, "upright posture is only the consequence of the higher development of the brain". So wrote von Baer, the great 19th century embryologist. Von Baer went on to remark that "all differences between men and other animals depend upon construction of the brain". Thus we emerge with a story of man's evolution from an ape-like ancestor in which the development of upright posture, tools, skills and speech are all a consequence of an increase in brain size. As he became more intelligent, man began to walk upright, to use his hands to fashioning tools, to develop skills and cunning in hunting, and later farming, and, on the way, developed language into the articulate form it takes today.

Unfortunately for this presentation, it is not actually based upon anything more than "intelligent speculation". When the facts began to be discovered they were in plain contradiction to this story. Our African ancestors, or near cousins, were small brained ape-like creatures (Australopithecus) whose anatomy (from skeletal remains) indicate a clear upright posture, no different from our own. Why did this come first, before increased brain size? Gould argues that it was the movement from tree-dwellers to ground animals that initiated the subsequent evolution of our ancestors to an upright posture. Walking upright left the hands free for using tools - the beginnings of our mastery of material surroundings. In turn this initiated the development of the larger brain required for more complex tasks.

However, the idealist tradition, of which Plato was the most eloquent spokesman, "encouraged an emphasis on thought as primary, dominating, and altogether more noble or important that the labour it supervised." It was the subtle and pervasive influence of this idea that was simply accepted as axiomatic by scientists such as von Baer when presenting the traditional picture.

Other essays in this book cover equally interesting and instructive problems. Why did the Irish Elk become extinct? - not, as was claimed, because its antlers were so large that they stuck in the trees! Who was the naturalist on the Beagle when Darwin made his epoch making journey? - it was not Darwin! Stephen Gould also assesses the popular portrait of past thinkers, such as catastrophists, and shows how they have often been misrepresented as cranks in a manner more reminiscent of caricature than proper history. This is indeed a thought-provoking book!