Product Description

The Bell Curve, The Moral Animal, The Selfish Gene-these and a host of other books and articles have made a seemingly overwhelming case that our genes determine our behavior. Now, in a new book that is sure to stir controversy, one of the world's leading evolutionary biologists shows why most of those claims of genetic destiny cannot be true, and explains how the arguments often stem from a fundamental misunderstanding of evolution itself. "You can't change human nature," the saying goes. But you can, Stanford biologist Paul Ehrlich shows us in Human Natures, and in fact, evolution is the story of those changing natures. He makes a compelling case that "human nature" is not a single, unitary entity, but is as diverse as humanity itself, and that changes in culture and other environmental variations play as much of a role in human evolution as genetic changes. We simply don't have enough genes to specify behavior at the level that is often asserted. Never has knowledge of our evolutionary past been more important to our future. Developing intelligent strategies for antibiotic use, pest control, biodiversity protection-and even for establishing more equitable social arrangements-all depend on understanding evolution and how it works. A hallmark of Human Natures is the author's ability to convey lucidly that understanding in the course of presenting an engrossing history of our species. Using personal anecdote, vivid example, and stimulating narrative, Ehrlich guides us through the thicket of controversies over what science can and cannot say about the influence of our evolutionary past on everything from race to religion, from sexual orientation to economic development. A major work of synthesis and scholarship, Human Natures gives us the fruit of a lifetime's thought and research on evolution and environment by a modern master of scientific understanding. Ehrlich's innovative vision lights the way to a fresh view of human nature and evolution, bringing insight and clarity to urgent questions of where we are as a species, and where we may be headed.

Product Details

• Amazon Sales Rank: #898731 in Books
• Published on: 2000-08-01
• Original language: English
• Number of items: 1
• Binding: Hardcover
• 576 pages

Amazon.com
It's common to blame "human nature" for some of the unpleasant facts of life--road rage, say, or murder, or war. The problem with this convenient out, argues the distinguished scientist Paul Ehrlich, is that there really is no single human nature. Humans, it's true, share a common genetic code with remarkably few large-scale differences (if all but native Africans disappeared from the planet, he notes, "humanity would still retain somewhat more than 90 percent of its genetic variability"); and evolution has endowed us with capabilities shared by no other species. But for all that, he adds, our separation into haves and have-nots, weak and strong, and other such categories is more often than not a product of cultural evolution, a process far more complex than the mere mutation and adaptation of a few genes. And, in any event, those genes "do not shout commands to us about our behavior," Ehrlich says. "At the very most, they whisper suggestions."

In this wide-ranging survey of what it is that has made and that continues to make us human, Ehrlich touches on a number of themes--among them, his recurrent observation that science has taught us little about how genes influence human behavior. (Instead, he notes wryly, "science tells us that we are creatures of accident clinging to a ball of mud hurtling aimlessly through space. This is not a notion to warm hearts or rouse multitudes.") He urges that scientists take a larger, interdisciplinary view that looks beyond mere genetics to the larger forces that shape our lives, a view for which Human Natures makes a handy, and highly accessible, primer. --Gregory McNamee

From Publishers Weekly
Most people know Ehrlich as the environmentalist who brought the world's attention to the overpopulation problem in the 1960s. But this Stanford biologist has also enjoyed a long, eminent career exploring evolution. In his new book, he combines his scientific research and environmental concerns into an enlightening narrative of humanity's evolution. Ehrlich surveys the most important research on the origin and rise of hominids and current ideas about the ascent of language and consciousness. He accepts that we are the products of evolution, but he finds the current trends of evolutionary psychology and genetic determinism to be hopelessly simplistic. Instead, Ehrlich shows how genes, culture and the environment together create a complexity that, he says, science still barely grasps. The 100,000 or so genes in human DNA, he contends, could never determine the 100 trillion connections between the neurons in our brains. Evolution may shape our brains generically, but the culture and environment in which we grow up control its fine details. Moving into the more recent past, Ehrlich charts how cultural (rather than biological) evolution has created civilizations, and how it has later destroyed many of them. Finally, he shows how an understanding of human evolution can inform our ethics and our decisions about how to run our societies. It shows, for instance, that under their skin, all humans are practically identical genetically speaking; we cannot pretend that race has any biological significance. We still have a long way to go from an evolutionary point of view: our ancestors spent millions of years living in small groups and dealing with the immediate struggle of finding food, and we have not yet adapted to the globalized society or such problems as human-created climate change. Although Jared Diamond and others have plowed this ground before, Ehrlich's book is so well researched and so elegantly presented that it stands as one of the best introductions to human evolution in recent memory. And that along with Ehrlich's name recognition should help this break out from the usual. science audience. 20,000 first printing; 8-city author tour; national radio interviews; national print advertising.
Copyright 2000 Reed Business Information, Inc.

From Library Journal
Ehrlich (biological sciences, Stanford; The Population Bomb) has written a very informative book on the human animal that emphasizes the essential framework of organic evolution. He focuses on the survival value of bipedality, intelligence, language, and technology for the emergence of our species and its success. His analysis also points out the roles that art, violence, sexual behavior, and the coming of civilization have played in the biocultural evolution of humankind. "All of our natures are a product of our histories, biological and cultural," Ehrlich claims. But he stresses that the complexity, flexibility, and diversity of human natures cannot be explained primarily in terms of genetic inheritance. Scrutinizing gene-culture interactions, his study points out that there are not enough genes to account for the range of human natures. Consequently, the powerful influences of society and the environment on the formation of human natures must also be considered. Glaringly absent is a critical analysis of the unfortunate threat that some religions present by rejecting the fact of evolution, ignoring the overpopulation problem, and dismissing outright an evaluation of both social issues and human values within a naturalistic outlook. Even so, Human Natures is an important contribution to an evolutionary understanding of and appreciation for our species in terms of science and reason. Recommended for all academic science collections.DH. James Birx, Canisius Coll., Buffalo, NY
Copyright 2001 Reed Business Information, Inc.

Customer Reviews

Brilliant..
One of the best books about how we produced our cultures. Ehrlich is just brilliant..

Ehrlich as Sisyphus
Ehrlich's central thesis - that there is not just one human nature but many seems eminently reasonable on the surface. But Ehrlich sidesteps the most convincing evidence! His "culture theory" rebuttal of the straw man of "genetic determinism" singularly fails to review the many twin and adoption studies showing that people inherit their behavior as well as their appearance.

Ehrlich becomes especially annoying when he repeats the mantra that human races do not exist and brands the genetic argument over race and sex differences "racist" and "sexist." Consider the following sets of data. If race was an invalid concept and genes had little or no predictive power, the findings I summarize would not be so consistently found.

For example, although IQ tests were invented by Whites and standardized on mainly White populations, dozens of studies now show that East Asians, whether tested in North America or in Pacific Rim countries, typically average higher than Whites, scoring in the range of 101 to 111. Caucasoid populations in North America and in Europe typically average an IQ of 100. African populations living south of the Sahara, in North America, and in the Caribbean have mean IQs of from 70 to 90.

Ehrlich also fails to mention that IQ scores are related to brain size and that the races differ in brain size. Over a dozen magnetic resonance imaging (MRI) studies have found a r = 0.40 relation between brain size and IQ. Racial differences in brain size have been established using four quite different procedures: MRI, autopsies, endocranial volume, and external head measures. The brains of East Asians (Koreans, Chinese, Japanese) and their descendants consistently average a larger volume (about 17 cm3) than those of Europeans and their descendants, and 97 cm3 larger than those of Africans and their descendants.

Changes in brain size have cascading effects on other traits, including athletic ability. Blacks have narrower hips than Whites or East Asians which gives them a more efficient stride and enables them to run and jump better. The reason why Blacks have narrower hips, however, is because they give birth to smaller brained babies. During evolution, increasing cranial size meant women had to have a wider pelvis.

Why did Ehrlich neglect to mention all these data if he's interested in the truth about human natures (in the plural)? Wouldn't we expect the evolutionary process to have different effects in different environments? In the wake of the success of The Bell Curve and other recent books about race by Arthur Jensen, Michael Levin, and me (Race, Evolution, and Behavior) that provide race-realist answers to the question of differential group achievement, there has been an intense effort to get the 'race genie' back in the bottle. Its sad when a scientist with so many accomplishments and so Herculean a reputation as Ehrlich takes it upon himself to assume so Sisyphean a task.

Once more into the breach . . .
Paul Ehrlich enters the lists of "nature vs nurture" by fulminating against the straw-man of "genetic determinism". One would have thought this joust would have been called for "time" by now. In his attempt to triumph over this rather ephemeral opponent, Ehrlich has performed a prodigious task. This well-written and comprehensive view of human evolution is a valuable resource. A massive footnotes and references collection grants this book value far above the narrative itself. Ehrlich, a practiced writer and researcher, brings many years of work and observations of the human condition to this massive overview. He strives to explain who we are and how we arrived at our current stature. He further warns that our lack of understanding of our backgrounds may threaten our future.

"Human nature" is often cited as a foundation for many behavioural traits. The fallacy of that moral expression is revealed in the variety of our habits. Ehrlich recognises that variation in his title and goes on to explain it in this book. While the genetic foundation of our behaviour is being solidly established by much field research, he ultimately concludes much of that basis is overriden by our cultural influences. Much of our confusion about "nature versus nurture", he contends, lies in the rapid pace of humanity. Compared to most other species, our mental development raced past the other animals - with language as the accelerator pedal. Since the genetic base for most traits is so slow and nearly muted, our development agriculture, religion and urban society virtually overwhelmed our "animal instincts". The prime example, of course, is the massive impact we have on our environment.

Ehrlich's key in assessing genetic versus cultural input lies [logically!] in the structure of the brain. When he wrote this book, the human genome was thought to be comprised of 100 000 genes. With that figure halved, he concludes the genome hasn't the power to command the billions of neurons with their trillions of connections that comprise the human brain. This "gene" shortage, he avers, suggests the genome hasn't the capacity to drive human behaviour to any significant degree. This rather simplisitic enumeration ignores the fact that the entire genome, whatever the number of genes, must be highly interactive in many areas of the body - the brain is simply another part of the mechanism. He is apparently unaware of the brain research showing how similar interactions have been mapped within the brain. Genes merely kickstart the process, they don't need to "control" our behaviour.

Ehrlich takes the usual swipes at Richard Dawkins as he builds his narrative. Like so many others, Ehrlich's reading of "The Selfish Gene" appears to have ceased at the title. To him, the "Great Leap Forward" of some fifty thousand years ago emancipated us from the shackles of our genetic heritage. With the development of language [which wouldn't have happened without a biologically endowed "voice box"], human cognition, hence behaviour, launched on a new course. Ehrlich asserts we've never looked back, but also warns our capabilities should be adapted to now look forward. Our abilities threaten the biosphere with an intensity and scope no other species possessed.

In his conclusion, the author nearly reverses all his prior narrative. He urges humanity to develop a better understanding of its place within nature. That, of course, means a full programme of understanding animal behaviour and the mechanisms animals and plants use to stay alive and reproduce. Our evolution, particularly the cultural input, has led us to believe we are distinct from Nature. Ehrlich recognises the dangers of such an attitude and urges us to overcome it. Although an excellent synthesis and supremely comprehensive, it's unfortunate that Ehrlich's prejudices blinded him to create a problem that doesn't exist. Nobody argues for "biological determinism" in an absolute sense - certainly not Dawkins. Where Ehrlich is correct is that we must increase our knowledge of how nature works and undertake the tasks needed to stop and reverse the spoilage under way.
[stephen a. haines - Ottawa, Canada]