Thursday, February 4, 2010
More ancient humans
Turns out that if you're of European descent, your great-great-great-great granddad was most likely a farmer. Mark Jobling of the University of Leicester in the U.K. and his colleagues found not only that agriculture seems to have spread westward via a new group of Neolithic people from the Near East, but also that these new farmers were incredibly successful with the local ladies, leaving their genetic traces in their modern male descendents.
"We focused on the commonest Y-chromosome lineage in Europe," Jobling said in a prepared statement. The team analyzed a single haplotype, R1b1b2 (which is carried by about 110 million men in Europe today) from 2,574 European men whose families had been living in the same location for at least two generations. This common haplotype, however, is not randomly distributed across the continent. "It follows a gradient from south-east to north-west," he said. About 12 percent of men in eastern Turkey have it, whereas some 85 percent of men carry it in Ireland.
Going back even further, researchers looking at why humans became so hairless speculate it was an adaptation to changing environmental conditions that forced our ancestors to travel longer distances for food and water. Okay, more than speculate...the ability to time when we lost our hair is pretty cool.
Wednesday, November 18, 2009
Effects of prenatal exposure of phthalates in boys
A new study in the International Journal of Andrology has raised a storm of concern that prenatal exposure to these chemicals could make boys less masculine in their play preferences.
Phthalates, which block the activity of male hormones such as androgens, could be altering masculine brain development, according to Shanna H. Swan, a professor of obstetrics and gynecology at the University of Rochester Medical Center and lead author of the new report [Los Angeles Times]. To test whether that link extended into behavior, Swan’s team tested women for phthalate levels midway through their pregnancy and then checked back in on the children four to seven years later.
The researchers asked parents to report their children’s patterns of play, but they knew they also had to separate any potential phthalate effect from the “nuture ” side of question. To determine how parental views might sway behavior, parents completed a survey that included questions such as, “What would you do if you had a boy who preferred toys that girls usually play with?” They were asked to respond with whether they would support or discourage such behavior, and how strongly [TIME].
The study of about 150 kids found that while girls were mostly unaffected, boys who had been exposed to the highest phthalate levels showed a lower likelihood than other boys to participate in what we consider typical rough-and-tumble male recreation—play fighting, pretending to play with guns, and so on. But the research might not imply the national masculinity crisis that some headlines suggest. Play in the most highly phthalate-exposed boys wasn’t “feminized,” Swan explains, since these kids didn’t preferentially play with dolls or don dresses. Rather, she says, “we’d describe their play as less masculine” [Science News]. Rather than play-fighting, she says, those boys tended toward “gender neutral” play like putting puzzles together or competing in sports.
Sunday, June 14, 2009
More animal adventures at the zoo
He focuses mostly on his personal interactions with the animals in the first half of the article (not to downplay those; a couple of moments as he describes them are amazing!), but I think the most important part of his article in the latter third where he discusses the health of animals when interacting with humans. Since my graduate work has been focused on what we can do to help enrich animals lives (including humans), I found this part particularly applicable to my own life and studies. But that's just me.
Speaking of, I should really be writing my thesis right now...which hopefully explains the sporadic posting over the past, well, two years, but hopefully that will soon change. In the meantime...hi ho, hi ho, it's off to word-processing I go...
Thursday, February 12, 2009
Hyenas ate humans
Was this just one poor sap who got on the menu, or was this a trend among the hyenas of old? Were we scavenged? Hunted for our delicious organs?