purepedantry | July 13, 2007Scientists have just documented (another) inheritable change in a species that occurred in response to a change in the environment -- in this case a parasite. Hence they have observed the process of natural selection.
In the latest issue of Science, Charlat et al. observed that the sex ratio in a species of Polynesian butterfly -- Hypolimnas bolina -- changed from 99:1 favoring females to parity in less than 10 generations. The sex ratio favored females because there is a parasite -- a bacteria called Wolbachia -- that selectively kills the male embryos.
However, in the space of ten…
purepedantry | July 13, 2007The Nikon Small World photography competition is starting up for another year. Check out this year's competitors here (the winners have not been announced but you can rate them yourself). The competition includes beautiful micrographs such as the one below -- the 2000 winner. Prizes are included so check it out the participation guidelines if you have pretty pictures.
More pictures and comment by Kate of Anterior Commissure.
purepedantry | July 11, 2007One of the ways that scientists study human decision making is through the study of behavior in simple games -- loosely lumped into a field called game theory.
Some of the most interesting and revealing findings involving such games is that human beings are not "strictly rational." Before everyone jumps all over me, let me define that statement. Strictly rational in this sense means that the behavior of human beings during these games does not always maximize expected value of the numerical (usually monetary) reward over the long-term. In laymans terms, if you offer someone $5 with no…
purepedantry | July 11, 2007It's your money. An article in the Scientist deals with the financial returns for investments in research:
Twenty-eight percent. This is the figure Edwin Mansfield, a now-deceased economics professor at the University of Pennsylvania, obtained after wrestling with an army of assumptions to pinpoint a likely return on research payoffs.1 In 1991, Mansfield estimated that the rate of return on investing in academic research (across all disciplines) was 28%, meaning each dollar put into research would yield $1.28 in social and economic benefits within about a decade.
As part of the study,…
purepedantry | July 11, 2007Johnathan Wolff publishing in the Guardian cites the case of Naomi Oreskes as to why the equal time idea of journalism doesn't work for science:
I learned to shut my mouth on the topic after hearing a lecture from a San Diego philosopher of science, Naomi Oreskes, who reported the results of a review of the scientific literature on global warming. Not one peer-reviewed scientific article, of the hundreds she surveyed, denied that the earth was warming or that human action was at least partially responsible. The sceptics, she argued, were largely members of independent thinktanks, often…
purepedantry | July 10, 2007Go to the Simpsons movie site and make your own.
Here's mine.
Hat-tip: Omni Brain.
purepedantry | July 9, 2007The story about two weeks ago that eldest children have a significantly higher IQ was really big news, but I didn't have time to talk about it then. Now, that I have had time to look at the articles about it, I think that some statement about what the word "significant" means is in order.
The NYTimes reported:
The eldest children in families tend to develop higher I.Q.'s than their siblings, researchers are reporting today, in a large study that could settle more than a half-century of scientific debate about the relationship between I.Q. and birth order.
The average difference in I.Q. was…
purepedantry | July 5, 2007Thanks to Marginal Revolution for this astonishing story. It refers to a man who sued his wife's new lover for damages on the grounds that the new beau had alienated his wife from him. And the guy won!
All Arthur Friedman wanted to do was liven things up in the bedroom. He and his wife, Natalie, had been married for ten years, and things were getting a bit, ahem, stale. Instead of the usual suspects -- lingerie, porn, toys, weekend get-a-ways -- Arthur had one tiny request: he wanted to watch his wife engaging in sexual acts with other men and women. (We imagine her response was something…
purepedantry | July 5, 2007Actually that isn't fair. It isn't wrong. The percentage of difference just depends heavily on what you define as a difference.
So argues an editorial by Jon Cohen in the latest issue of Science:
Using novel yardsticks and the flood of sequence data now available for several species, researchers have uncovered a wide range of genomic features that may help explain why we walk upright and have bigger brains--and why chimps remain resistant to AIDS and rarely miscarry. Researchers are finding that on top of the 1% distinction, chunks of missing DNA, extra genes, altered connections in gene…
purepedantry | July 3, 2007Encephalon 26 is now up at the new and improved Neurophilosophy blog. Happily the Neurophilosopher has now joined Scienceblogs. Welcome!
purepedantry | July 3, 2007Rats show a type of "generalized" altruism:
Rats that benefit from the charity of others are more likely to help strangers get a free meal, researchers have found.
This phenomenon, known as 'generalized reciprocity', has only ever been seen before in humans. A good example, says Michael Taborsky of the University of Bern, Switzerland, is what happens when someone finds money in a phone box. In controlled experiments such people have been shown to be much more likely to help out a stranger in need following their good luck.
In humans, such benevolence can be explained by cultural factors as…
purepedantry | July 2, 2007In 2004, the FDA assigned a "black box" warning on prescription of antidepressants to patients under 25. This was because of a flurry of anecdotal evidence linking the beginning of treatment with SSRIs to increases in suicide risk and because of placebo vs. drug trials that showed these increases in risk on the beginning of treatment for these age groups.
At the time, there was not enough evidence to release such a warning, but the FDA was under spectacular pressure. Mothers testified before committees about their lost children. Not heard -- or at least not heard sufficiently -- were the…
purepedantry | July 2, 2007Brian Doherty from Reason has an interesting article on NY's place as a libertarian mecca:
New York City is the celebrated center for many vital aspects of American culture: publishing, finance, and the arts. It rarely has been credited, however, as a cutting-edge leader in political ideologies.
But New York also is the breeding ground for a unique and growing American political tendency -- the modern American libertarian movement. It might seem ironic that a city that has been, at various times, one of the most overly governed and poorly governed of American cities should be a launching…
purepedantry | June 29, 2007Matt Nisbet at Framing Science cites an article by DJ Grothe and Austin Dacey arguing the negative:
Women, people of color, and GLBTs have consistently faced discrimination that substantially diminishes their basic life prospects-access to housing, health care, education, political participation, employment, and family benefits. Additionally, they have suffered violence and intimidation. For minorities defined by race, sex, and sexual orientation, civil rights movements were necessary to correct such grievous ill-treatment.
But do unbelievers really suffer comparable harm? Atheists are not…
purepedantry | June 28, 2007It is so exceedingly rare that I get to say something positive about stars. Usually all I have to say is some crap that Paris Hilton did or that Madonna decided to purchase another child from Africa. So I was pleased to be tipped off by Vaughan at Mind Hacks about this: did you know that Natalie Portman is on a published paper?
It was an imaging paper using near-infrared spectroscopy to measure the development of the visual cortex of infants. It was published during her time as an undergrad at Harvard under he real name -- Natalie Hershlag.
Anyway, here is a link to the paper.
Was she…
purepedantry | June 28, 2007Madam Fathom has a great piece on the results of fellow Sinai researcher John Morrison's study into cognitive improvement with estrogen treatment. (I would note, however, that hormone replacement therapy is still not recommended for anything other than the acute treatment of menopause because of negative cardiovascular side-effects associated with it.) (OVX = ovariectomized)
A new study by John Morrison at Mt. Sinai School of Medicine investigated this issue by OVXing old and young rhesus monkeys, and treating half of each group with estrogen. The group then tested the monkeys on a task of…
purepedantry | June 27, 2007The NYTimes has a excellent summary of the progress in the study of evolution of development (evo-devo). Scientists have been surprised to discover over the years that a relatively small number of closely-related genes control the body plan of animal species, even when those species' body plans differ dramatically. Apparently these same genes are being applied in diverse ways to organize very different body plans.
An example of one of the genes that organizes development is BMP4:
What Dr. Tabin and colleagues found, when looking at the range of beak shapes and sizes across different finch…
purepedantry | June 26, 2007C. Ford Runge and Benjamin Senauer, writing in Foriegn Affairs, summarize the likely effects of corn-based biofuels on the world food supply. Take home message: the biofuel craze has led to skyrocketing food prices which -- along with government subsidies and tariff protections to domestic corn producers -- has the potential to starve the poorest in the world.
Money quote:
Now, thanks to a combination of high oil prices and even more generous government subsidies, corn-based ethanol has become the rage. There were 110 ethanol refineries in operation in the United States at the end of 2006,…