Ethics and Evolution

Ethics and Evolution
“All the understanding in the world will neither increase nor diminish the force of the intuition that this is beautiful and that is ugly.” Thomas Huxley, 1893 Romanes Lecture

As I pointed out in my first essay (Atheism and Ethics), one of the most common criticisms of atheists is that without supernatural authority to define right and wrong, they can’t make reliable ethical judgments. Their only option according to the conventional wisdom is to adopt “moral relativism”, in which ethical decisions depend upon the individual making them or the circumstances under which they’re made. Thus, for example, a citizen of South Carolina in the early nineteenth century would have been wrong to help an escaped slave, because southern society at that time endorsed slavery. This criticism ignores the fact that every moral system is relative to some degree. Otherwise it would be impossible to distinguish things like of stealing to feed ones children from stealing merely to acquire another’s property.

Of course, this is not what the critics intend, when they accuse atheists and agnostics of “moral relativism.” They mean instead that nonbelievers are adrift in a sea of impossible choices, at best unable to condemn crimes like incest or child pornography, because we have no basis for deciding that these are wrong, and at worst incapable of opposing monsters like Hitler or Stalin. Nothing could be further from the truth. In fact, I venture to say that thoughtful atheists, who develop their own ethical standards, are more comfortable in their beliefs, more rational and consistent in their judgments, and on the whole more humane and compassionate than those who rely on conventional religion.

How can I support such a claim? The easiest way would be to exploit the deficiencies in faith based morality: the arbitrary edicts, antiquated viewpoints, and capricious, often cruel penalties that have been handed down unquestioningly from one generation to the next. By now the list of Old Testament prohibitions and punishments spelled out in Leviticus has become a comedic cliché, like the “Letter to Dr. Laura” at Snopes. Com. ( but these Draconian laws were not intended to be humorous. In Biblical times they were anything but funny. Their more recent manifestations in the Crusades, the Inquisition, or the Salem witch trials were deadly serious too. Even contemporary Christianity contains elements, like the Dominionists, who view the Church’s ancient rigor with nostalgia.

I prefer to take a more positive approach by describing how non-believers arrive at their own ethics in a systematic and natural way that has the added virtue of an empirical basis. The starting point is the observation that many animals behave in ways that we would characterize as moral in humans. South American vampire bats live in small groups. In the mornings, when they return to their roosts, successful hunters share their blood meals with bats who weren’t so lucky. The reason for sharing? Bats have such a high metabolism and blood is such a low energy food source, that unsuccessful bats could starve to death within a couple of days. Fewer bats in the group means fewer potential donors to return the favor. Regardless of the evolutionary rationale, it’s difficult to regard this behavior as anything other than generosity. Gorillas and chimpanzees routinely console members of their troops who’ve been bested in fights. They don’t congratulate the winners, mind you, but comfort the losers. They exhibit similar solicitude for members of their troops who’ve been injured or who have lost mates or offspring. In humans we call this compassion.

Captive chimpanzees have drowned in retention moats while trying to save other chimps who’ve fallen in the water. In laboratory experiments Rhesus monkeys will go without eating for days rather than administer electrical shocks to other monkeys in order to earn food. Among African meerkats sentries risk their lives to warn other meerkats of approaching predators. A long and growing list of animal species from wolves and elephants to penguins and whales behave in ways that can best be described as ethical.

How do these behaviors evolve? Viewed simplistically natural selection – the “survival of the fittest” as Huxley called it – would seem to favor selfishness over altruism. A number of theories have been proposed to explain the apparent contradiction. One hypothesis is that natural selection works on groups as well individuals. Groups whose members cooperate have a competitive advantage over those that are composed entirely of self-centered individuals. This mechanism fell out of favor during the 1960s, when critics like Richard Dawkins observed that a few selfish individuals could sabotage any group and destroy its reproductive advantage; but recent versions of the theory may have bypassed this difficulty.

Another possible explanation involves what’s known as “kin selection”, which was recognized by
Darwin in his second major work, The Descent of Man. Since members of social groups tend to be genetically related to each other, they can increase their overall reproductive success by helping one another. In some circumstances the net effect may even outweigh a loss incurred by the individual who renders aid. Finally there’s “reciprocal altruism.” When assistance provided by one member of a group to another can be repaid at a later time, the genetic predisposition to help each other tends to be reinforced within individuals.

Key to all of this is a concept we haven’t yet discussed called “synergy”. It occurs when combined human effort produces results that cannot be achieved by individuals. Human society is replete with examples of synergy from sports teams to construction crews. Our species seems to be uniquely suited to this form of cooperation, so much so that it’s tempting to surmise that we evolved specifically to take advantage of it. Because of synergy, human relationships are rarely “zero sum” exchanges and ethical behavior, which is essentially a way of facilitating interaction, may be more powerfully selected than we have supposed.


A growing body of evidence supports an inherited predisposition for humans to behave ethically. This hypothesis helps to explain why we feel so good about acting well. It also enables us to understand why the same ethical maxims appear so commonly in disparate cultures. Recognizing that our better impulses can be explained in evolutionary terms allows us to accept them more confidently and to incorporate them into a comprehensive intellectual philosophy of life. We can reject the caveats that we discussed at the beginning of the essay from those who believe that religion is the sole source of moral wisdom. For my part I’m happy to rely on several million years of evolution.

Recommended Reading:
Moral Minds: How Nature Designed Our Universal Sense of Right and Wrong – Marc D. Hauser
(2006, Eco/ Harper-Collins, New York)
Hauser’s principle thesis: the human brain has heritable neural circuits subserving moral behavior.

Primates and Philosophers: How Morality Evolved – Frans de Waal
(2006, Princeton University Press, Princeton)
Precursors of human ethical behavior in chimpanzees and other great apes.

Evolution and Ethics – 1893 Romanes Lecture – Thomas Huxley
Stylish, but pretentious by today’s standards. Huxley’s lecture covers the history of ethics at great length, but eventually gets around to his main thesis. Good source of elegant quotations.

Biological Altruism – The Stanford Encyclopedia of Philosophy
A succinct, informative article.

“Evolution and Ethics: An Idea Whose Time Has Come? (Parts I & 2) - Peter A. Corning, Ph.D.
Journal of Social and Evolutionary Systems, 19(3): 277-285 - © 1996, JAI Press
Extremely informative, well reasoned and well written, with useful links to other sources.
If you want to read more, go to this site first.

This site needs an editor - click to learn more!

Related Articles
Editor's Picks Articles
Top Ten Articles
Previous Features
Site Map

Content copyright © 2022 by AJ Hill. All rights reserved.
This content was written by AJ Hill. If you wish to use this content in any manner, you need written permission. Contact BellaOnline Administration for details.