Walt Whitman wrote, “I am large, I contain multitudes”. David Barash might well pen a similar line to describe his field of study, but his intended meaning wouldn’t be metaphorical. Barash, professor of psychology at the University of Washington, and best known for the book Madame Bovary’s Ovaries, is a man enamored with microorganisms – moreover, the “host manipulation” that is their stock and trade.
Consider this example of organismic hijacking from an article Barash recently wrote for The Chronicle of Higher Education:
The life cycle of a trematode worm, known as Dicrocoelium dentriticum, involves doing time inside an ant, followed by a sheep. Getting from its insect host to its mammalian one is a bit of a stretch, but the resourceful worm has found a way: Ensconced within an ant, some of the worms migrate to its formicine brain, whereupon they manage to rewire their host’s neurons and hijack its behavior. The manipulated ant, acting with zombielike fidelity to Dicrocoelium’s demands, climbs to the top of a blade of grass and clamps down with its jaws, whereupon it waits patiently and conspicuously until it is consumed by a grazing sheep. Thus transported to its desired happy breeding ground deep inside sheep bowels, the worm turns, or rather, releases its eggs, which depart with a healthy helping of sheep poop, only to be consumed once more, by ants. It’s a distressingly familiar story … distressing, at least, to those committed to bodily “autonomy.”
Distressing, indeed, and all the more so once you’re introduced to Barash’s comparable, if not as macabre, application of the principle to homo sapiens.
More troublesome than the fact that our genes — at least in theory — are eternal, whereas our bodies are ephemeral, is the caterpillar’s question to Alice: Who are we? Or, rephrasing Lenin by way of Glendower, Who’s calling and who’s heeding? The biologically informed answer is that we’re not all that different from those alarming rat/tapeworm, ant/trematode, flea/bacteria relationships, only this time it’s genes/body. Unlike the cases of parasites or pathogens, when it comes to genes manipulating bodies, the situation seems less dire to contemplate, if only because it is less a matter of demonic possession than of our genes, ourselves. The problem, however, is that those presumably personal genes aren’t any more hesitant about manipulating us than a brainworm is about hijacking an ant.
This clearly isn’t a theory standing outside the ring of controversy, nor one that doesn’t cross lines into multiple disciplines, many leagues wide and deep — but that makes it all the more intriguing, right? Sort of like flirting with the abyss where freewill once and for all can’t find its way back home. I guess it depends on your view of excitement…and I need to get out more often. But the article is worth reading in any case.
Link to David Barash’s book on amazon
Interview with Barash in L.A. Weekly
Recent article by Barash in the L.A. Times