Nature vs. Altruism

Tuesday, July 17, 2012

In a posting at Why Evolution Is True, Jerry Coyne discusses what it would take to disprove the theory of evolution. I found the following two points, taken together, interesting in light of a notion I have seen bandied about to the effect that altruism exists in nature or has somehow been selected for. (To be clear, each of these things are not what we actually see.)

  • The observation that most adaptations of individuals are inimical for individuals or their genes but good for populations/species.  Such adaptations aren't expected to evolve often because they would require the inefficient process of group or species selection rather than genic, individual, or kin selection.  And indeed, we see very few features of organisms that seem inimical to organisms or their genes but useful for the population or species. One possible exception is sexual reproduction.
  • Evolved "true" altruistic behavior among non-relatives in non-social animals. What I mean by "true" altruistic behavior is the observation of an individual sacrificing its reproductive output for the benefit of individuals to which it is either unrelated or from whom it does not expect to receive return benefits.  In this "true" altruism your genes give benefits to others and get nothing back, and this shouldn't evolve under natural selection. And, indeed, we don't see such altruism in nature. There are reports that vampire bats regurgitate blood to other individuals in the colony to whom they're unrelated, but those need confirmation, and there may also be reciprocal altruism, so that individuals regurgitate blood to those from whom, one day, they expect a return meal. Such cooperation can evolve by normal natural selection. [bold added]
I am not familiar enough with studies of "altruistic" behavior to know whether the term "altruism" in such contexts is normally used to mean something more like cooperation, but I have always disliked the term. I strongly suspect that most biologists, at least, don't mean some kind of non-cooperative phenomenon. Nevertheless, the use of the ethical term fosters misunderstanding of such work (not the least because of the actual meaning of altruism) among non-scientists in the general public. It also lends false credence to the misconception that the overwhelming evidence in favor of evolution somehow also indicates that self-sacrifice is a "natural" way for man to live. If anything, the opposite is true.

-- CAV


Steve D said...

But cooperation is not exactly the correct term for the concept biologists are trying to convey. Altruism is definitely closer to their intended meaning. Altruism in a biological sense means an organism lowering its own reproductive success to insure the eventual survival of a larger number of its genes. More specifically, it means sacrificing a small number of genes specific to its own genome to insure the survival of a greater number of genes it shares with kin, clan or species.

‘One possible exception is sexual reproduction.’

So, sexual reproduction sacrifices fifty percent of the individual’s genes upfront. Biologists have a hard time imagining an individual benefit so large to make that worth while. But it’s possible that things were different long ago when sex evolved. Perhaps there was significant pressure from the environment to make this true. The parasite theory holds promise. And it may also be that once such a complex system has evolved it might be impossible to unravel it.

‘It also lends false credence to the misconception that the overwhelming evidence in favor of evolution somehow also indicates that self-sacrifice is a "natural" way for man to live. If anything, the opposite is true.’

This is definitely true. But I would definitely say it’s up to us to make sure people understand the difference and to make sure that they also realize the theory of natural selection in no way informs ethical theory (or vice versa) any more than say for example string theory does.

I’d just say that using our reason to compare altruism against selfishness, deciding which way is the best and acting on our soundest judgment is the “natural’ way for man to live. That’s what we are designed to do. (Or using a modified paraphrase from a related subject: if God wanted us to fly, he would have given us a brain to figure how to do it.)

Gus Van Horn said...


Thanks for the clarification. I still dislike the term, but your description makes its use more understandable.


Anonymous said...

The example I have heard is a duck quacking and thereby revealing itself to approaching predators but also sounding an alarm for the other ducks.

But then why don't all the altruistic ducks get eaten first?

Gus Van Horn said...

In that example, you could argue that, since other ducks in a similar situation would (and probably have) alerted it at some point in the past, that that reaction to predators does not solely benefit other ducks.

Steve D said...

The ducks are closely related and so they all share a lot of genes. If the duck in question warns the others, but he dies because of it, more of his genes might be passed on through the others than would be through himself (if he survived but many in his flock died). Therefore, it might be in his gene’s own selfish interest to create a somewhat altruistic organism. This at least is what Richard Dawkins opines in his book ‘The Selfish Gene’. His argument does make sense.
In other words the genes are selfish but the organism they give rise to may sometimes seem altruistic since their evolutionary purpose is to propagate their genes not themselves.

Gus Van Horn said...

True, but the action is also not even really analogous to altruism on the level of the individual animal.

Anonymous said...

The typical example of altruism given in biology is that of vampire bats. Blood is a poor source of nutrition, and every vampire bat is about two meals away from starving to death. If one gets closer to starvation, other bats will regurgitate their meals, feeding the starving bat.

What the "so altruism is morality!!!" crowd forget is that in this example, bats also will refuse to help other bats if the other bats don't ALSO share meals, or if they attempt to simply be freeloaders. The idea isn't "I'm helping you because it's the right thing to do"; rather, it's "I'll scratch your back, you scratch mine".

So-called "reciprochal altruism" is nothing more than rational self-interest and investment. In the case of bats, that investment is in good-will, so that if something happens and they can't feed enough other bats will like them enough to help out. Far from being anything like a wellfare state, this is akin to my college buddies and I chipping in to help a friend pay rent, on the understanding that next month he buys us beer.

Gus Van Horn said...

Thank you, Anon. Your analysis is consistent with Coyne's. Thanks for fleshing it out.