Monday, December 29, 2008

PLEDGES TO ABSTAIN WORTH THE AIR THEIR SPOKEN INTO

Teenagers who pledge to remain virgins until marriage are just as likely to have premarital sex as those who do not promise abstinence and are significantly less likely to use condoms and other forms of birth control when they do, according to a study released today.

The new analysis of data from a large federal survey found that more than half of youths became sexually active before marriage regardless of whether they had taken a "virginity pledge," but that the percentage who took precautions against pregnancy or sexually transmitted diseases was 10 points lower for pledgers than for non-pledgers.

"Taking a pledge doesn't seem to make any difference at all in any sexual behavior," said Janet E. Rosenbaum of the Johns Hopkins Bloomberg School of Public Health, whose report appears in the January issue of the journal Pediatrics. "But it does seem to make a difference in condom use and other forms of birth control that is quite striking."


Wednesday, December 24, 2008

BACTERIA ALTERING DNA OF HOST

This stuff gets curiouser and curiouser, doesn't it? Found the following on Wired. What would it mean if bacteria were altering our genetic inheritance or that it did so in the past? One more accidental trigger for change and speciation.

"Wolbachia is a prolific parasite, having carved out a niche for itself in some 70 percent of all invertebrate animals. But it's doing more than living in their cells: it's changing their very DNA in a way that could affect how scientists study genetics and evolution across the animal kingdom."

Read more at Wired.

Tuesday, December 23, 2008

GOULD'S THE PANDA'S THUMB

The following I got from my reading this morning over at the Border's Books near our new condominium. I walked over because my car is snowed in and I don't have a snow shovel. We left our snow shovel back in Spokane at the house we sold there. The new owner is getting a lot of use out of it, no doubt, but we could use it here, where Vancouver is experiencing near record snowfall. Anyhow, evolution has certainly developed many unique ways to foster reproduction. I found this one in Stephen J. Gould's The Panda's Thumb:

[SNIP]
Consider the curious life of a male mite in the genus Adactylidium, as described by E.A. Albadry and M.S.F. Tawfik in 1966. It emerges from its mother's body and promptly dies within a few hours, having done apparently nothing during its brief life. It attempts, while outside its mother, neither to feed nor to mate. We know about creatures with short adult lives—the mayfly's single day after a much lengthier larval life, for example. But the mayfly mates and insures the continuity of its kind during these few precious hours. The males of Adactylidium seem to do nothing at all except emerge and die.

To solve the mystery, we must study the entire life cycle and look inside the mother's body. The impregnated female of Adactylidium attaches to the egg of a thrips. That single egg provides the only source of nutrition for rearing all her offspring—for she will feed on nothing else before her death. This mite, so far as we know, engages exclusively in sib mating; thus, it should produce a minimal number of males. Moreover, since total reproductive energy is so strongly constrained by the nutritional resources of a single thrips' egg, progeny are strictly limited, and the more females the better. Indeed, Adactylidium matches our prediction by raising a brood of five to eight sisters accompanied by a single male who will serve as both brother and husband to them all. But producing a single male is chancy; if it dies, all sisters will remain virgins and their mother's evolutionary life is over.

If the mite takes a chance on producing but a single male, thus maximizing its potential brood of fertile females, two other adaptations might lessen the risk—providing both protection for the male and guaranteed proximity to his sisters. What better than to rear the brood entirely within a mother's body, feeding both larvae and adults within her, and even allowing copulation to occur inside her protective shell. Indeed, about forty-eight hours after she attaches to the thrips’ egg, six to nine eggs hatch within the body of a female Adactylidium. The larvae feed on their mother’s body, literally devouring her from inside. Two days later, the offspring reach maturity, and the single male copulates with all his sisters. By this time, the mother’s tissues have disintegrated, and her body space is a mass of adult mites, their feces, and their discarded larval and nymphal skeletons. The offspring then cut holes through their mother's body wall and emerge. The females must now find a thrips’ egg and begin the process again, but the males have already fulfilled their evolutionary role before "birth." They emerge, react however a mite does to the glories of the outside world, and promptly die.
[PASTE]

Gould in the brief essay which includes the snippet above is talking about why almost all sexed species produce males and females at about the same 50/50 ration. The
Adactylidium mite is the exception that tests the rule.

Monday, December 22, 2008

SOCIALISM FOR CAPITALISTS, CAPITALISM FOR SOCIALISTS WORKERS

According to Steven G. Brant:

“The funny thing is, I've known that a significant portion of the US economy is Socialistic for years. ‘What are you talking about?’, you ask? ‘The Military Industrial Complex,’ I answer.

“You do know that all military weapons are purchased using ‘cost plus’ contracts, in which businesses are guaranteed a profit, don't you? And that literally every weapons system comes in over its original budget... and that those cost overruns are absorbed by the government, not the arms manufacturer? There is no Capitalism in the Military Industrial Complex. It's all Socialism, justified by the concept that these weapons are so important to American security that the companies that manufacture them have to be guaranteed a profit, so they don't accidentally go out of business. (By the way, I worked in contracting years ago at the Army Corps of Engineers. So, I know something about how military contracts work.)

“Now, getting back to the death of Capitalism in America as a whole, don't be so sad. You know the expression: ‘From every emergency, there's a chance for something new to emerge.’? Well, that's where we are.”

Read more of his essay here: http://www.huffingtonpost.com/steven-g-brant/capitalism-is-dead-now-wh_b_127016.html