Friday, March 22, 2013

Capacity for Cooperation—Part 1



A battle has been raging in biology for a few decades, about the role of cooperation in evolution. Is evolution primarily driven by competition or cooperation? Darwin posited his theory of evolution on the basis that competition for life dominates in the natural world. He saw that far more offspring of any given species are born than can survive in any given situation and location, so there's an intense struggle for survival—which later came to be dubbed “survival of the fittest.” (That’s not Darwin’s term, but was coined by enthusiasts who followed him.) Those critters most fit will survive and those less so will perish...it's that simple and that brutal. 

Any tiny advantage—any favorable minuscule genetic mutation that pops up—may offer a critter a wee bit better chance of survival that its competitors. If the critter does have a better chance of staying alive, it has a better chance of reproducing and sending that advantage into the future. In contrast, a tiny disadvantage in a genetic mutation may see the critter die early and fail to send its genes into the future. It's the end of the line for that less favorable mutation.

So far, what I have described is no cause for the disagreement that prevails between the opposing biological camps. They both agree…thus far. The debate enters when we come to consider what's called “inclusiveness fitness”—when a critter sacrifices itself for others. Martyrdom prevents one's genes from continuing on, and since the propagation of one's genes into the future seems to be a driving factor, how can one explain the systematic willingness of some members of a species to sacrifice themselves for others, when that sacrifice terminates one's genes? If all critters are driven solely by the urge to send their genes into the future, how does one account for those who voluntarily give up that drive?

Richard Dawkins is a prominent leader of the camp that considers our genes to be firmly in control—that we are “driven” by our “selfish genes.” He writes that our behavior is literally determined by our self-seeking genes, simply to transport them into the future. Dawkins’s camp insists that inclusive fitness is the only way to explain why some members of a species will sacrifice themselves. All members of a bee colony, for example, share common genes (they are all sisters). Thus, if a sister sacrifices itself, it's doing so to protect the family—the family's genes will survive, even if the individual bee dies. Similarly, a human being may sacrifice himself for a close family member. By doing so, his genes will get terminated, but the family genes may go on.

That's all fine. There’s still no real argument among biologists. The debate comes in because there are a few situations where individuals will sacrifice themselves for others who are not family members. What's going on here? How do you explain why someone would willingly give up her chance to send her own genes into the future, just to help foreign genes to survive? Does this not seem to violate the principle that we are controlled by our selfish genes? This is the core of the disagreement between the biology camps.

More on our capacity to cooperate next time…

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