Sex on Six Legs_ Lessons on Life, Love, and Language From the Insect World - Marlene Zuk [19]
Lamarck was quite interested in invertebrates, a subject not much studied by naturalists in the late eighteenth and early nineteenth centuries, and he was intrigued by the idea that they exhibited such fixed behaviors. It seemed reasonable to him and many of his contemporaries that doing something, whether following an odor trail or learning to count, could cause a permanent change in the body, and that such changes could be inherited. Of course, we now know that the genes cannot be influenced in exactly the way that Lamarck imagined. And it is likely that both learned and instinctive behaviors evolved together. Most behaviors, even in insects, are due to a combination of influences from the environment, and hence subject to learning, and influences from the genes, and hence instinctive, making the old argument somewhat moot.
Dan Papaj, a biologist at the University of Arizona, doesn't believe Lamarck himself was correct, but he does wonder if there aren't new ways in which learned behavior could influence evolution. He works with a variety of species, from butterflies to parasitic wasps, to see just how learning operates in nature. He points out that the idea that fixed behaviors could have arisen from something an ancestral insect learned to do is not as far-fetched as it might seem. Researchers in the fields of robotics and artificial intelligence are particularly interested in how changes in stimuli—that is, the response a computer gets when it executes an action—could then make the computer's actions more sophisticated. It would be amusing if the behaviors so derided by Fabre and Cunningham turned out to pave the way for better, and more flexible, computers.
Finally, social insects are well known for their genetically hard-wired altruism; honeybees can't help committing suicide when they sting an intruder in defense of the colony, because the stinging apparatus remains imbedded in the victim, tearing the innards of the bee asunder after the sting. But it has just come to light that ants, at least, can also choose to rescue their kin from harm even when the peril is novel. Elise Nowbahari and her colleagues in France and the United States took ants, partially submerged them in sand, and restrained them with a nylon filament so that their bindings were concealed under the surface. The scientists then re-leased either strangers or nest mates of the victim and watched the ants' behavior. If, and only if, the entrapped ant was from the same nest, the other ants hurried over, dug her out, and bit the snare away. Ants from foreign colonies, even though they were the same species, were left to struggle helplessly.
Such a complex sequence of behaviors pushes the boundaries of what we thought an insect could learn. And if the same ability applies to species other than ants, we might want to rethink those sticky traps that attract cockroaches and trap them, alive and kicking, on the surface. If the roaches become able to rescue their fellows by nibbling through the glue, you have to start wondering if they might then be capable of plotting revenge.
Chapter 2
Six Legs and a Genome
SOME of the most cutting-edge discoveries about insect molecular genetics, and therefore about how genes do and don't dictate complex behavior, have been made because Gene Robinson was tired of harvesting fruit. As a student worker on a kibbutz in Israel, he was asked to "help out with the bees temporarily, and since I was bored to tears picking grapefruits, I volunteered. I remember I was smitten that very first day."
In his correspondence, he glosses over exactly why the bees were so appealing, but despite parental skepticism (he summarizes his mother's response as: "No doctor, no lawyer, where did we go wrong?"), Robinson went on to pursue a master's and later a Ph.D. in entomology. Now at the University of Illinois, he still