Top positive review
genetic and cultural coevolution
on September 30, 2002
This scholarly opus written in a conversational style by Paul R. Ehrlich, Professor of Biological Sciences at Stanford University, sets forth the thesis that human nature is the product of genetic and cultural coevolution. He states that while genes predispose and constrain human behavior, its cultural expression is undetermined and highly variable. This view leads him to advocate the use of the expression, "human natures," which denotes cultural pluralism. In effect, he also argues against the position that genetic determinism fully explains human behavior.
One example he gives concerns the nature of language. Human beings may have inherited the genetic capacity for language, but they do not develop languages according to predetermined forms. Development of languages in human populations thus illustrates the undetermined quality of evolution in human behavior.
The book is roughly divided into two parts, so that the first makes a gradual transition into the second. In the first part, the author offers a detailed and complete account of human biological evolution. In the second part, he explores the evolution of human behavior, from its primitive counterparts in the behavior of other primates to its complex modern manifestations.
All throughout, his approach, according to his own description, is to summarize the latest scientific research and then to offer his own opinion on issues that are largely inconclusive. As an in-depth compendium, the book makes a good reference.
In the second part, Ehrlich tackles intriguing topics in evolutionary psychology--the evolution of language, sex, war, religion, art, ethics, to name a few. I believe any careful reader will come away, as I did, with insights. For example, I was enlightened by his observation that while our hundreds of thousands of years of genetic evolution as small-group hunter-gatherers allow us the capacity for meaningful personal interaction with perhaps 90-220 individuals, we live in modern societies organized around millions or even billions of citizens. This fact explains the impersonality and alienation in modern states besides the incredible inhumanity of wars waged on a modern scale.
However, I came away somewhat dissatisfied with the second part for two reasons. First, Ehrlich does not offer any unified theory upon which to interpret cultural evolution. On this question, he says that human culture is indeed vast and it awaits the next crop of geniuses to construct such a theory a la Darwin. Second, it became apparent, at least to me, that while the author is in his element when he draws upon disciplines cognate to his own, such as cultural anthropology, he is limited in covering the contributions of less related disciplines like economics or art history to understanding cultural evolution. But I would not expect anyone, Ehrlich included, to be so complete in scope.
I might suggest that the most rewarding way of reading the second part is to treat it as little essays, from as long as a chapter to as short as a section, in which the author is guided throughout by the interpretative framework of genetic and cultural coevolution.
This book is worth reading--and keeping--for anyone interested in human evolution.