There’s a fascinating article in the New York Times about a theory by evolutionary biologist David Haig dealing with pregnancy and how it’s a struggle between the developing fetus and the mother:
“Pregnancy is absolutely central to reproduction, and yet pregnancy doesn’t seem to work very well,” he said. “If you think about the heart or the kidney, they’re wonderful bits of engineering that work day in and day out for years and years. But pregnancy is associated with all sorts of medical problems. What’s the difference?”
The difference is that the heart and the kidney belong to a single individual, while pregnancy is a two-person operation. And this operation does not run in perfect harmony. Instead, Dr. Haig argues, a mother and her unborn child engage in an unconscious struggle over the nutrients she will provide it.
Dr. Haig’s theory has been gaining support in recent years, as scientists examine the various ways pregnancy can go wrong.
In short, the theory suggests that the fetus is an efficient parasite that battles with the mother for limited resources and, from a strictly scientific outlook, that’s a pretty accurate description that is being supported by more and more research. It goes on to talk about how changes to certain genes can result in various problems during pregnancy and even later into adult life and it all starts in the womb.
Because of the negative connotations associated with the word “parasite” I fully expected this article to cause a big blow up among the anti-abortion bloggers out there even though the word itself doesn’t show up in the article, but overall the response I’ve seen out there has been surprisingly subdued. Most folks seem to be resisting the urge to try and apply the scientific findings to their personal political viewpoint on the issue of abortion. Sure, there’s a few folks out there on the anti-choice side that are having a screaming fit over the news article, but overall most folks seem to be taking it in stride.
PZ Myers points out that not only is this not a new idea, but there are examples in nature that could be considered even more troubling—such as how male and female organisms can evolve differently to try and maximize their advantages in sexual reproduction:
This sets up a cycle of counter-adaptations in the population. If a male acquires a mutation that increases his fitness at the expense of his mate’s—for instance, if some component of his semen works on her brain to suppress her interest in remating—it will spread through the population due to its positive effect on male fitness, even though it reduces female fitness. Subsequently, a female who acquired a counter-adaptive resistance to the male’s hormonal sabotage would have an advantage, and that gene would spread through the population, reducing male fitness by making them less capable of controlling female reproduction. Then, of course, males could evolve some other sneaky way of maximizing their reproduction rate—vaginal plugs, secretions that make the mated female unattractive to other males, proteins that put her ovaries into overdrive to produce more eggs now at the expense of the female’s long term survival.
It all sounds improbable and dystopian, but all of these mechanisms and more have been observed in that exceptionally promiscuous species, Drosophila.
For me, this raises interesting ideas about the nature of any so-called “Intelligent Designer” that might exist. Given examples such as Drosophila it implies that any Intelligent Designer responsible for such a creature would have to be a pretty twisted fellow to come up with a model of reproduction such as that. Vaginal plugs? Proteins to force ovaries into overdrive? What kind of a sick bastard IS this Designer guy anyway?