Altruism: Genetic or Cultural Evolution?

( -- The origins of altruism, the willingness to make personal sacrifices for the benefit of others often unknown to us, has perplexed evolutionary social scientists and biologists for years.

Why do people willingly to go to war, give blood, contribute to food banks and make other sacrifices often at considerable risk to themselves and their descendents? Evolutionary explanations based on both genes and culture have been proposed for this , which is unique among vertebrates.

In all likelihood, it is evolutionary forces acting on socially learned behavior (culture), a group of UC Davis researchers argue in a paper published this month in the .

The group, led by Adrian Bell, a doctoral candidate in ecology, based its conclusion on estimates of the degree of genetic and cultural variation found between groups versus within groups. Natural selection acts and depends on variation.

“Our numbers show … and we argue that socially learned beliefs, or our culture as we define it here, is a much better candidate to explain the pro-social tendencies that humans have in large-scale societies,” Bell says. The main reason for that is that between groups are much greater than genetic differences.

Bell prepared the paper, which appears in the Oct. 13 issue, with co-authors Peter J. Richerson, a professor emeritus in the Department of Environmental Science and Policy, and Richard McElreath, an associate professor in the Department of Anthropology.

More information: rather than genes provides greater scope for the evolution of large-scale human prosociality, PNAS 2009 106:17671-17674; published online before print October 12, 2009, doi:10.1073/pnas.0903232106

Provided by UC Davis (news : web)

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Oct 23, 2009
"Why sex?" has been explored quite a bit, although names of researchers or papers are escaping me at the moment... My brain seems to have failed me, as I was just reading a paper about it the other night. PBS took a good look at it here: http://www.pbs.or...dex.html and you should be able to find a ton more.

Basically, sexual reproduction mixes the genes and gives offspring higher survival chances. There was a recent experiment on a particular creature, I think it was a flatworm, that could reproduce either sexually or asexually--the sexually reproduced offspring fared better because of the genetic diversity.

Oct 23, 2009
I should also add that it also probably has some other intrinsic values, such as being able to pick which genes you want your offspring to have, etc. Even if asexual reproduction offered the same genetic variation as sexual reproduction, it wouldn't allow for mate selection.

That may not be the proper evolutionary approach, but I hope it helps.

Oct 23, 2009
in order for altruism to form the genetic ability to outcompete and have extra capacity (profit) that one could then grant. the granting of extra capacity over time would sort out how it would be favored, with the acts that were returning less and resulting in less output (fertile) would decline and those that resulted in more output, would increase.

thought is not solid enough to drive evolution, evolution of thought tendencies creates the behavior and thought adapts to it to make it reasonable.

those that dont have as much altruism do not think this, but they will rationalize a reason why if thye notice the difference.

the mind adapts to the differences that arize out of genetic variation. if your deaf in one ear, the mind adapts. if your missing your foot, the mind adapts.

minds flexibility is to adapt functionally to the body so that it maximizes fitness (in the abstract).

not enough room to explain... sigh

Oct 24, 2009
Evolutionary explanations based on both genes and culture have been proposed for this human behavior, which is unique among vertebrates.

I hope that this isn't trying to imply that this is a purely human behavior, because animals also show this behavior.

Oct 24, 2009
Good call, Paradox, I didn't even catch that!

Oct 24, 2009
and paradox's statements would imply that these behaviors come way before higher complicated thoughts that can then back track and get it wrong. :)

Oct 25, 2009
"..which is unique among vertebrates"... isn't this observed in non-vertebrates as well?

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