Science News Review

Science news for the average citizen.

Cosmic Billiards, Extinction, Love, Sex and Depression

Sep 14 at 6:06pm by Aileen

…plus a Blog Slam just for fun!

This week there’s lots of news from the fields of biology, medicine and psychology about people. What they want, what they do, and what makes them that way. But I’ll start with the famous extinction event that wiped out the dinosaurs ~65 million years ago, making room for humans to evolve at all.

U.S. and Czech astrophysicists reported that a Large Asteroid Breakup May Have Caused Mass Extinction at that time. They created a clever simulation of the disintegration of a giant asteroid in the belt roughly 100 million years ago, which caused an asteroid bombardment of the earth and moon as fragments crossed our path.

Yet more evidence to add to the iridium layer that tells us what most likely happened to those gentle and not-so gentle reptilian giants who once dominated the planet.

On the subject of extinction, the World Conservation Union reported its Red List of Threatened Species added more than 16 thousand species of plants and animals last year.

Extinction Crisis Escalates: Apes, Corals, Vultures, Dolphins All in Danger lets us know in no uncertain terms that it doesn’t necessarily take a cosmic billiard ball to cause a big biodiversity loss on this planet. Something to think about.

Another endangered animal - one of our world’s rarest primates - has been trying to teach University of Arizona Biodesign Institute researcher Brian Verrelli and his team about the evolution of color vision.

Color Night Vision in the Aye-Aye presents a real puzzle to evolutionary theorists. Though Aye-Ayes (and related lemurs) split from primate lines that eventually became humans, apes and monkeys just around the time of that dinosaur-killing cosmic billiard ball, they do have full trichromatic color vision. Deal is, Aye-Ayes are totally nocturnal animals - coming out only at night - thus have no practical need of or use for trichromatic color vision.

The puzzle is why the ability to see in color was not lost in Aye-Ayes over the eons, since they don’t need or use it. The findings have challenged previous views and some assumptions about how evolution works. Researchers note that the genes for green and red opsins are found on the X chromosome, which helps explain why females have better color vision than males. Aye-Ayes show little or no accumulation of mutations as would be expected.

Of X and Y chromosomes and Why Genes of One Parent are Expressed Over Genes of the Other, the journal BMC Evolutionary Biology reports research on the marsupial platypus and wallaby that also challenges prevailing evolutionary theory.

It turns out that genomic imprinting - the expression of one parent’s gene while the other parent’s gene is repressed - isn’t associated with the X or Y chromosomes after all. Surprisingly, it’s not associated with ancestrally imprinted chromosomes either.

Reports BMC, “The results of the distribution studies suggest that imprinted genes were not located on an ancestrally imprinted chromosome, nor were they associated with sex chromosomes. Rather it appears that imprinting evolved in a stepwise, adaptive way, with each gene or cluster becoming imprinted as the need arose.”

Since the word “sex” has been introduced, check out research from cognitive scientists at Indiana University report that they’ve figured out What Men and Women Really Want in a Mate. It’s about time!

Though these findings aren’t exactly earth-shattering, surprising, or even mildly at odds with conventional evolutionary theory. Turns out that men go for the pretty girls while women are more interested in security and commitment. Duh.

The story told by the head researcher won’t surprise anybody. “Ancestral individuals who made their mate choices in this way — women trading off their attractiveness for higher quality men and men looking for any attractive women who will accept them — would have had an evolutionary advantage in greater numbers of successful offspring.”

From such politically incorrect (but quite expensive) statements of the obvious, we get some sociological findings from internet entrepreneur Andrew Keen at an ESRC conference at the University of York. The subject is blogs and bloggers… like me!

Force for Democracy - Or Information Chaos? Expert Forum Spotlights Blogging informs us that Keen thinks interactivity and user-generated content on blogs is leading us into a social morass of “less culture, less reliable news and a chaos of useless information.” Huh. And here I thought I was helping to bring interesting science news to the internet.

If I cared what Keen thinks I’d probably get a little depressed about the pointlessness of my meager attempts. And if I were depressed, researchers reporting in the Annals of Internal Medicine warn me that I may not get the therapy I need from my health care provider.

Depression therapy not by guidelines warns that primary care physicians do not give their patients long-term care consistent with established quality standards. Showing that “additional efforts are needed to improve the treatment of depression.”

Though I sure don’t know what that would be, particularly for young people diagnosed with depression. Who, in line with modern medical thinking, are simply dosed with whatever the current psychoactive drug with the most lobbyists behind it, and sent home.

The New York Times offered a depression report from the CDC about depression in young people, Suicide Rises in Youth: Antidepressant Debate Looms.

“The increase was particularly sharp among adolescents, especially girls, according to the Centers for Disease Control and Prevention, which released the figures yesterday. The timing of the increase coincided with a public debate in the United States and overseas over whether the antidepressants increased the risk of suicide in a small percentage of young people who took them. In late 2004, after public hearings, the Food and Drug Administration called for drug makers to put a prominent “blackbox” warning on the drugs’ labels, cautioning about the possibility of increased suicide risk in minors.”

The government talking heads, researchers in psychology and psychiatry, drug manufacturers and insurance company lobbyists will work all this out eventually, we hope. Meanwhile, young and old who suffer from clinical depression will still be getting inappropriate treatment from family doctors who aren’t specialists but can dispense drugs. Oh, well.