The Gleaners

Entries from March 2008

EPCs (“extra-pair copulations”)

March 19, 2008 · Leave a Comment

An evolutionary biologist reflects on Eliot Spitzer’s extramarital encounters (and, now, it appears that of his successor, David A. Paterson, as well) in an op-ed piece in the LA Times (via Arts & Letters Daily).  David Barash writes:

One of the most startling discoveries of the last 15 years has been the extent of sexual infidelity (scientists call it “extra-pair copulations” or EPCs) among animals long thought to be monogamous. It’s clear that social monogamy — physical association and child rearing between a male and a female — and sexual monogamy are very different things. The former is common; the latter is rare.

He goes on to note the biological and evolutionary foundations for male strayings and also observes that from the perspective of women, ” Power-as-pheromone is pretty much the default.”  Thus, putting the two together, it is no surprise that humans seem by nature to be polygamus.

Not surprisingly, before the homogenization of cultures that resulted from Western colonialism, more than 85% of human societies unabashedly favored polygamy. In such societies, men who accumulate power, wealth and status gain additional wives and consorts. In avowedly monogamous cultures, successful males accumulate a wife and often additional girlfriends. Even if, thanks to birth control technology, they do not actually reproduce as a result (and thus enhance their evolutionary “fitness”), they are responding to the biological pressures that whisper within men.

He also includes this amusing anecdote:

A story is told in New Zealand about the early 19th century visit of an Episcopal bishop to an isolated Maori village. As everyone was about to retire after an evening of high-spirited feasting and dancing, the village headman — wanting to show sincere hospitality to his honored guest — called out, “A woman for the bishop.” Seeing a scowl of disapproval on the prelate’s face, the host roared even louder, “Two women for the bishop!”

Categories: Human Behavior

You get what you pay for

March 5, 2008 · Leave a Comment

Yesterday, Yahoo!News had an article about a newly published study that showed that “the well-known ‘placebo effect’ works even better if the dummy pill costs more.” In the study, people “got a light electric shock and were offered what they were told was a painkiller.”

Half were given a brochure describing the pill as a newly approved painkiller that cost $2.50 per dose and half were given a brochure describing it as marked down to 10 cents.

Eighty-five percent of volunteers who thought they were getting a $2.50 pill said they felt less pain after taking it, compared with 61 percent of those who thought they were getting a discounted drug.

The researcher asks an interesting question: “How do we give people cheaper medication, or a generic, without them thinking it won’t work?”

Coincidentally, a week earlier, The Boston Globe ran an article about the same phenomenon; this article was primarily about a study of wine tasters, but it also mentioned the effect of cost on the effectiveness of drugs. In the article, “Grape Expectations,” researchers examined wine tasters — who, it must be said, seem always to be picked on when people study expectational delusions (see previous post “The wacky world of wines“) — with unsurprising results.

SCIENTISTS AT CALTECH and Stanford recently published the results of a peculiar wine tasting. They provided people with cabernet sauvignons at various price points, with bottles ranging from $5 to $90. Although the tasters were told that all the wines were different, the scientists were in fact presenting the same wines at different prices.

The subjects consistently reported that the more expensive wines tasted better, even when they were actually identical to cheaper wines.

The experiment was even more unusual because it was conducted inside a scanner – the drinks were sipped via a network of plastic tubes – that allowed the scientists to see how the subjects’ brains responded to each wine. When subjects were told they were getting a more expensive wine, they observed more activity in a part of the brain known to be involved in our experience of pleasure.

What they saw was the power of expectations. People expect expensive wines to taste better, and then their brains literally make it so.

After the researchers finished their brain imaging, they asked the subjects to taste the five different wines again, only this time the scientists didn’t provide any price information. Although the subjects had just listed the $90 wine as the most pleasant, they now completely reversed their preferences. When the tasting was truly blind, when the subjects were no longer biased by their expectations, the cheapest wine got the highest ratings. It wasn’t fancy, but it tasted the best.

Categories: Human Behavior · Science