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Thales Volume 5 Issue 11

Sex and Stress

Thales could predict a brouhaha. Imagine the Pavlovian salivation of many reporters when they spot BOTH words ‘sex’ and ‘stress’ in the title of a published research report. Never mind what the article is actually about. Thales can read their minds: “Is sex the new antioxidant? If I don’t have sex I can’t cope!” Thales always hopes that science and the media work together to responsibly report research findings to the public. Thales also knows that in the current climate of sound bites and sensationalism, this is not likely. So what did happen?

In the “Advances by Faculty” section of this newsletter, Science Continuum draws attention to the discovery by Aurora Nedelcu and colleagues that, for a multicelllular alga Volvox canteri, sex and activation of sex genes was triggered by reactive oxygen species, products of heat stress. The findings are the first of the kind for multicellular organisms, and significantly add to the debate about the evolution of sex. As Nedelcu and colleagues point out, the three major hypotheses about the evolution of sex are ‘variation’, ‘selfish DNA’, and ‘DNA repair and mutation’, with their recent finding adding weight to the last hypothesis.

Now that is pretty straight forward, isn’t it? If sex is a response to heat stress which damages DNA, and if DNA can be repaired during meiosis during germination of the zygospore, then ..... Well the adaptive significance of sex in these circumstances is suggested, is it not? Do you notice any mention of humans or of psychological stress? Of course not. But...

At least the science specialty news outlets were reasonably in context. For example,
ScienceNow [Science magazine] says “[Nedelcu] and her colleagues grew asexual volvox in the lab, where they measured the free radical concentrations by adding a chemical that fluoresces when exposed to free radicals. When the researchers turned up the heat, the free radical concentration shot up in the first 10 minutes and doubled within 2 hours. By that time, the sex-inducing gene was active and the volvox began making male and female gametes instead of asexual ones ... The advantages of sex are twofold, Nedelcu says. For starters, the resulting hard shell helps the organism wait out the tough times. But perhaps more importantly, it mixes up parts of each gamete's chromosomes and thus can accelerate the repair of DNA damaged by the free radicals. That's consistent with a somewhat controversial theory that holds that sex evolved as a means to repair DNA damage, she says.” However, not being able to resist a ‘human hook’ to this story, ScienceNow added “Some people take vitamins to reduce their exposure to cell-wrecking free radicals. A round alga called volvox protects itself against these rogue molecules through sex.” Probably fair enough. A pretty good report.
The Korean BRIC feed of the ScienceNow article can be accessed at
http://bric.postech.ac.kr/biotrend/science/science_view.php?nNum=88137 [ignore the foreign font type prompt]

A very few of the popular press outlets covered this news in a reasonable manner.
CBC news online announces ‘Heat a turn-on for algae’ and says “ Why sex evolved is a source of heated debate among biologists ... About 15 years ago, Michod and his colleagues proposed an alternative DNA-repair hypothesis. According to the DNA-repair hypothesis, the process of dividing up parental genes during sexual reproduction also repairs any DNA damage in the sperm and eggs. That way, any damage to the parents' DNA isn't passed on. Proponents were looking for evidence from multicellular organisms like the algae.” Which, the article says, they found. The article summarizes the actual research method as well. Pretty good.
http://www.cbc.ca/stories/2004/06/08/sci-tech/algae040608

Unfortunately, there were many sensationalized, out of context, and even nonsensical popular press treatments of this research. You can see it in article titles like ‘Is Sex a Cure for Stress?’, ‘Need Sex? It’s probably something about stress’, ‘Stress - die Wurzel der Sexualität [roughly Stress - the root of sexuality], and Die Zeit Stress macht Algen heiß [roughly Stress makes algae hot]. Suffice it to look at two articles, one in Canada and one in the US.

The Vancouver Province trumpeted ‘FINALLY, STUDY FINDS A GOOD REASON FOR SEX’ “Need sex? You're probably just stressed, Canadian and U.S. researchers say.” Now wait a minute, Nedelcu wasn’t talking about humans! And what about all the other studies that formed great hypotheses about the evolution of sex - were they not studies that found good reasons for sex? FINALLY, indeed. Oh, and they couldn’t resist adding “In their study, Nedelcu and Michod watched algae have sex.” Voyeurs all! Are there no end to the metaphors?
http://www.bpoi.org/forum/archive/index.php/t-2665.html

The Arizona Republic asks ‘Stress a good stimulant for sex?’ “Why buy Viagra when stress is free? Which is not precisely what researchers at the University of Arizona are saying . . . . but still, they say stress can lead to enthusiastic sex. ... So who says we shouldn't go out in the mid-afternoon Valley sun?”
http://www.azcentral.com/health/men/articles/0622stress-sex-ON.html

Well, you get the gist. A scientist may MAY see a wry humor in the Viagra quip, or a humourous play on words with the ‘watching sex’ crack but what about the general public?
Wouldn’t you expect an otherwise intelligent person to at least think “ Is sex the new antioxidant? If I don’t have sex I can’t cope!” Or as the Globe and Mail reported in their article ‘Why sex triumphs over all’ “As Homer Simpson might put it: Ummmm . . . sex . . . ummm . . . good.”
http://www.theglobeandmail.com/servlet/ArticleNews/freeheadlines/LAC/20040612/STRAUSS12/science/Science

Stress and Sex, indeed!