Nesting and Spring-loaded Parasitism

While enjoying your eggs, you should consider what primitive social insects do with theirs. Why? Because it may be essential to our understanding of social behavior and, hence, the notion of moral and ethical behavior. I’m reading Nowak, Tarnita, and E.O. Wilson’s 2010 article (and 43 pages of supporting materials), “The evolution of eusociality” from Nature (466/doi:10.1038/nature09205).

This is a contentious paper, I should add, because it postulates “multilevel selection” that operate at the group or species level. It is remarkable in several ways. First, it uses mathematical terminology to explain aspects if the theory of eusociality (literally: “good sociality” but, theoretically, the highest levels of social interaction) that we rarely see in papers on evolutionary theory. Specifically, ideas like “global updating” are introduced to explain why traditional methods of explaining eusociality are plagued by false assumptions about the spatial distribution of mating opportunities. I’m reminded of my own critique of the microevolution versus macroevolution distinction that pervades anti-evolution arguments: why would nature (or God for that matter) prevent hybridization of species while making it easy for genetic drift within a species? We either have a failure of imagination, the deliberate introduction of barriers to hybridization just to fool all of us or maintain a prescribed order, or we have a continuous transition from micro to macro effects (hint: there is actually no real distinction).

But back to eggs. E.O. Wilson and colleagues suggest that the earliest forms of sociality were among the parasitic wasps, like the Tarantula Hawk. Accumulate prey, stuff eggs into them, and then move on. Next, icky stuff happens in the prey. One allele change can turn the move on behavior off when the local environment is sufficiently rich, however, and then moms and offspring hang around in colonies together. Not mathematical is the use of “spring-loaded pre-adaptations” to describe this transition. The loss of wings among worker ants is a spring-loaded trait, as is the inability of fire ants to recognize aliens from other colonies; they can’t go anywhere or accurately target others for attack.

The 43 pages of supporting materials demonstrates that modern scientific theories, like the “Dark Matter” work previously described, are just not very simple. They are, arguably, just simple enough and no more so. Still, the more than 130 evolutionary biologists who objected to the Wilson paper argue that the previous theory (kin selection) was a simple solution that demanded no additional complexity. The naked mole rat and termites may object, but perhaps a synthesis is forthcoming.

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