No gender gap in arousal time

A study from McGill University in Montreal challenges the conventional wisdom that women take longer to become sexually aroused than men.

A study from McGill University in Montreal challenges the conventional wisdom that women take longer to become sexually aroused than men. Irv Binik, a psychology professor and director of the Sex and Couple Therapy Service at Royal Victoria Hospital, had men and women watch separate sexually explicit films and measured their level of arousal with special thermographic cameras. The cameras8212;which use the same technology as military night-vision goggles8212;detect temperature-related radiation emitted by objects, in this case the subjects8217; genitals.

Binik8217;s team kept tabs on the subjects8217; readings from another room. They found that both men and women began to be aroused within 30 seconds. Men reached maximum arousal in 665 seconds about 10 minutes, while women did so in 743 seconds. Although that was more than a minute longer for women, it wasn8217;t a statistically meaningful gap, the researchers found. 8220;There is no difference in the amount of time it takes healthy young men and women to reach peak arousal,8221; Binik said. The researchers expect their findings, to be published in the January issue of the Journal of Sexual Medicine, will help in the diagnosis and treatment of sexual dysfunction.

The tropics nurture marine species

The tropics serve as both the engine of new biodiversity and a museum where older species are preserved, according to a new research that might settle a long-running scientific debate. The study, based on fossil records dating back 11 million years, documented that many species evolved first in the tropics before moving to higher latitudes. Three researchers8212;University of Chicago geophysicist David Jablonski, University of California at San Diego ecologist Kaustuv Roy and University of California at Berkeley biologist James Valentine8212;reached their conclusion by tracing the lineages of 150 types of bivalves, a class of marine life that includes clams, scallops and oysters.

Over the past 11 million years, the scientists reported in last week8217;s issue of the journal Science, more than twice as many bivalve lineages arose in the tropics as in higher latitudes. These organisms also had a higher chance of survival in the tropics: 107 varieties of bivalves they surveyed outside the tropics went extinct, compared with just 30 in the tropics. 8220;It8217;s a really striking, surprising pattern,8221; said lead author Jablonski. 8220;I think we8217;ve killed the idea that the tropics is either a cradle or a museum of biodiversity. It8217;s both.8221;

8212;LAT-WP