Images of the Evolution of Morality
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Our title image helps to introduce the main themes in this exploration of the evolution of morality:
Charles Darwin was a gentle, quiet man, and a doting father. He and his relatives supported the abolition of slavery. He cringed at the harsh treatment of animals. —Not what one might expect, perhaps, for someone whose theory of evolution is often portrayed as leading only to selfish motives and moral relativism.

Quite the contrary: Darwin introduced thinking about morality in the context of natural history — how it might have originated organically. He recorded his thoughts in private notebooks as early as 1838 — alongside his earliest notions of species change, and published them finally in 1871 in Descent of Man. Darwin's new orientation continues to challenge and inspire us, both biologically and philosophically.

Read more abouta biological approach to morality

Despite Darwin's own efforts, many still assume his ideas imply that society ultimately reduces to unfettered competition and "survival of the fittest"—a doctrine misleadingly called "Social Darwinism." Such perspectives are widespread but ill informed, about both Darwin and how to apply our biological knowledge.

Read more onapplying the biology of morality culturally

Can algebraic expressions help us understand morality? Yes, sometimes. Cooperative or helping behavior can be costly to the individual, even if it benefits another organism. Natural selection would seem to favor cheaters: free-riders can proliferate at the expense of cooperators — and thereby eliminate any cooperation. But if the recipients are related genetically, or there is some form of reciprocity, benefits may exceed the costs and the behaviors may persist. The exact relationships of costs and benefits can be expressed mathematically and tell us when such behavior can evolve (as seen here in a table from a 2006 review article by Martin Nowak in Science).

Read more abouton the evolution of moral behaviors and outcomes.

Meet Mozu, a handicapped snow monkey, whose story may tell us something about how humans evolved moral feelings.

Mozu was born without hands or feet in a free-ranging troop in Japan. Mozu could not climb. Still, the other members of Mozu's troop did not move in the trees above her at a pace that would leave her behind, despite their ability to do so. They seemed cognizant — and also tolerant — of Mozu's handicap. Primatologist Frans de Waal claims that such observations help inform us that some moral sentiments seem rooted in human ancestry.

Read more aboutthe evolution of moral feelings

Vampire bats -- what an unlikely match for morality!

Vampire bats (Desmodus rotundus) roost in colonies, a very simple social organization. They must feed every few nights to survive. Sometimes, they fail. The bat then “begs” its neighbor by nuzzling its throat. The second bat often regurgitates a small amount of blood, nourishing the first bat. That seems to contradict the selfishness we typically associate with natural selection. How can this happen? Well, if you continue to watch the bats on successive nights, you find that eventually the second bat faces the same dilemma. The circumstance is reversed, and the first bat generally reciprocates. Here is a case of enhanced survival through cooperation — notably social in nature.

—But suppose one bat cheats! She begs for meals, but never “repays the favor.” That individual would reap the benefit, while bearing no cost. The trait of cheating could proliferate in the population and the system of sharing would collapse. The bats, however, seem “wise” to cheaters. They can recognize individuals and remember past events. A bat that has not reciprocated does not get another free handout. Tit for tat. Bats who cheat ultimately do not benefit. The system of fair exchange is kept in check. Is this morality? We obviously don't know about the intent or motivations of vampire bats. Yet the social system clearly enforces fairness. —And that illustrates the importance of social organization in modifying individual behavior.

Read more aboutthe evolution of moral systems

© 2009 Douglas Allchin | EVOLUTIONofMORALITY.net