The Elements of Evolution (50-1) Fitness Through Ignorance

Fitness Through Ignorance

Ignorance can favor group function. ~ American evolutionary biologists David Queller & Joan Strassmann

Hamilton’s calculus of altruism is incomplete. The flavors of ignorance can favor cooperation.

For many group behaviors, there are costs that only some individuals bear but ignorance of who benefits. Not knowing the future fosters kindliness.

Many ant colonies begin with a small group of unrelated queens. They coexist peaceably, producing the first generation of workers. But then the queens fight each other until only 1 survives. The cooperative efforts of the dead queens entirely benefit one who is no kin.

A queen who knew her destiny was death without a lineage of descendants would take her chances nesting alone, however dismal the prospects. Not knowing her fate creates the incentive to invest in cooperation.

Unrelated plasmodia come together to prosper as a heterokaryon; creeping along a forest floor as a superorganism, feeding on yeasts, bacteria, and decaying vegetation.

Conversely, social amoeba live as single-celled organisms during the good times, feasting on soil bacteria. Only facing starvation do they form a colonial structure.

Hard times push plasmodia and social amoeba to produce progeny. They form a fruiting body, growing a stalk that spews the spores of the next generation. The reason to sporulate during dire straits is that spores can outlast famine: inertly alert to opportunity when it arises.

The fruiting bodies of plasmodia and social amoeba represent a sacrifice of most members to pass on the spores of a relative few. Not knowing the outcome engenders cooperative endeavor.

Such cooperation is not always unalloyed. Some social amoeba cheat, managing to get more spores of kin produced than representative of the colonial population. Perhaps they pass their cunning on, contributing to furthering the intelligence of a species which sometimes must cooperate to survive.

◊ ◊ ◊

Ignorance of kin can kindle altruism. A colony of social insects includes different degrees of relatedness when a queen mates with multiple males. Individuals could theoretically identify others of their patriline – full sisters versus half – but they do not. Instead, they cooperate without such bias.

Similarly, a male bird or mammal may assiduously avoid rearing the brood of another male, but in situations where paternity is questionable, or in species that mix broods, males feed offspring without discrimination.

A veil of ignorance – whether of circumstance or about the future – can sow the seeds for cooperation and altruistic effort that might otherwise be missing.