Dugatkin discusses altruistic behaviors

Photo by John Nakano

As part of the Frontiers in Science Lecture Series, Dr. Lee Dugatkin spoke to Tech students, faculty and members of the Atlanta community last Thursday about “The Evolution of Goodness, Empathy and Justice.” Dr. Dugatkin teaches at the University of Louisville in the Department of Biology.

He has spoken at over 100 universities around the world and has published over 150 scientific articles. A self-described “evolutionary biologist, behavioral ecologist and historian of science,” Dr. Dugatkin’s primary area of interest is the evolution of social behaviors.

Dr. Dugatkin began by discussing Darwin’s famous On the Origin of Species, which details Darwin’s theories of evolution as well as his critiques of his own theories. One of Darwin’s biggest problems with his own ideas was the occurrence of altruism in non-human species, which seems to contradict the concepts of competition and natural selection.

Dr. Dugatkin defines altruism as helping others at a cost to oneself. For example, when ground squirrels sense a predator in the area, one ground squirrel will stand on its hind legs and give a loud, repetitive alarm call to warn fellow ground squirrels to get
to safety.

This obviously draws greater attention to the squirrel in question – so why increase the risk of being eaten just to help others when Darwin’s theories suggest that it should be “every man for himself”?

“This is really mysterious,” Dr. Dugatkin says. “It’s exactly the opposite of what we expect to see in nature.”

Certain species of bees demonstrate a similar phenomenon, in that when the bee stings a threat to the hive, the stinger is ripped from its body, and the bee dies. One possible explanation for acts of altruism in nature has to do with kinship – even though the ground squirrels and bees are endangering themselves, doing so gives their family and relatives a greater chance of survival. This ensures that their genes will still be passed down the genetic pool, which is in line with the theory of natural selection.

W. D. Hamilton, who developed the modern-day theory of altruism, created a formula to predict how likely animals are to risk their lives for others. Dr. Dugatkin summarizes the formula by stating that the “indirect benefit altruists accrue by helping their relatives” must outweigh the cost of performing the altruistic act.

A second theory exists to explain acts of goodness in nature, that of reciprocity. For instance, vampire bats must have a blood meal every forty-eight hours or they die. A bat who was unable to find food will often ask a second bat to regurgitate some of its meal so they can share.

A bat is far more likely to share if the bat asking has shared a meal too, suggesting that the bats keep track of acts of goodness in a “tit-for-tat” fashion.

The evolution of social behaviors in nature has further repercussions for empathy and justice, as well. One experiment in social behavior tested for empathy in rats by observing the lengths a rat would go to in order to rescue a fellow rat from an uncomfortable situation. Dr. Dugatkin’s most amusing experiment involved the sense of justice in capuchins.

The monkeys were trained to do the same task but received unequal rewards upon completion.  The monkey with the less desirable treat pitched a fit at the perceived injustice, throwing his “reward” back at the researcher.

Dr. Dugatkin would like to see more research into empathy and justice in non-humans in the coming years.

“We are fundamentally interested in why some people are nice and why some people are rotten,” Dr. Dugatkin says. “We can get some insight into that by studying other species.”