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Showing posts from March, 2008

Lizards Undergo Rapid Evolution after Introduction to a New Home

In 1971, biologists moved five adult pairs of Italian wall lizards from their home island of Pod Kopiste, in the South Adriatic Sea, to the neighboring island of Pod Mrcaru. Now, an international team of researchers has shown that introducing these small, green-backed lizards, Podarcis sicula, to a new environment caused them to undergo rapid and large-scale evolutionary changes. "Striking differences in head size and shape, increased bite strength and the development of new structures in the lizard's digestive tracts were noted after only 36 years, which is an extremely short time scale," says Duncan Irschick, a professor of biology at the University of Massachusetts Amherst. "These physical changes have occurred side-by-side with dramatic changes in population density and social structure." Results of the study were published March 25 in Proceedings of the National Academy of Sciences . Researchers returned to the islands twice a year for thre...

The bioecological model

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An email sent to Kristin Jacobson, Assistant Professor, University of Chicago Medical School Dear Prof. Jacobson, I was just leafing through my University of Chicago Magazine this evening when I came across the article summarizing your new grant. I have to say I was amazed. Though the author tiptoed around the area under investigation, you are entering some very choppy waters. The attempt to identify the genetic and biological contributions to anti social behavior and cognition is normally considered taboo, since it inevitably ventures into racial variables. Though I am familiar with some work reported in press releases and abstracts of journals, as you can see from my weblog, most researchers, considering the downside, tend to avoid such studies, even with the best of intentions. I can't help be reminded of the unfortunate lesson of Chicago's Dr. Bruce Lahn, with whom you undoubtedly have discussed your research interests. As was noted several years ago in the Wall Stre...

"...the biological pressures that whisper within men."

Do you Want a Man.... or a Worm? Los Angeles Times Among mammals, expecting monogamy tends to run against the grain of nature. By David P. Barash March 12, 2008 As an evolutionary biologist, I look at New York Gov. Eliot Spitzer's now-public sexual indiscretions and feel justified in saying, "I told you so." 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. At one point in the movie "Heartburn," Nora Ephron's barely fictionalized account of her marriage to reporter Carl Bernstein, the heroine tearfully tells her father about her husband's infidelities, only to be advised, "You want mo...

Impulsive Aggressive Behavior

Nature or nurture - why do some of us see red? University of Manchester researchers are investigating why some people remain calm in the face of life's niggles, while others 'flip' with little provocation. Recent studies using new brain-imaging technology have discovered that a change in the brain's neurochemical activity may be related to increased impulsive aggression (when someone unexpectedly reacts violently with little provocation, as opposed to someone deliberately 'looking for trouble'). Now psychologist Angela Rylands wants to deploy the University's world-leading HRRT PET brain scanner, based at its Wolfson Molecular Imaging Centre (WMIC), as part of a project to find out more. Angela said: "Positron emission tomography (PET) scanning has revealed that a deficit in brain serotonin neurotransmission may leave some people more prone to aggression and impulse control disorders. I want to establish to what extent such behaviours a...

Hormones, Genes and the Corner Office

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March 9, 2008 By EMILY BAZELON THE SEXUAL PARADOX Men, Women, and the Real Gender Gap. By Susan Pinker. 340 pp. Scribner. $26. Why do girls on average lead boys for all their years in the classroom, only to fall behind in the workplace? Do girls grow up and lose their edge, while boys mature and gain theirs? Ten years ago, no one would have thought to ask. The assumption that boys dominated at school as well as at work, while girls were silenced or ignored, seemed beyond dispute. But in her new book, “The Sexual Paradox,” a ringing salvo in the sex-difference wars, Susan Pinker stacks up the evidence of boys’ classroom woes and girls’ triumphs. “In the United States, boys are three times as likely to be placed in special education classes, twice as likely to repeat a grade and a third more likely to drop out of high school,” she writes. Tests of 15-year-olds in 30 European countries show girls far outstripping boys in reading and writing and holdi...