Human Nature

Don’t Feed the Reaper

And other news from science and technology.

(For the latest Human Nature columns on mandatory pregnancy, creationism, and more, click here.)

Italy’s IVF law survived a referendum. The law bans sperm donation and surrogate motherhood and requires women to implant simultaneously all the embryos they create. (For Human Nature’s take, click here.)

Astronomers found the smallest planet yet detected outside our solar system. It has seven times the Earth’s mass, is made of the same stuff, and might have an atmosphere. This is as small a planet as we can detect with present technology, so there’s no evidence that Earth-sized planets won’t be found as our instruments improve.

New evidence suggests that fat makes you age faster. Obesity adds about nine years to your biological age, as measured by cellular deterioration.

Psychiatrists are debating whether too many people are being classified as mentally ill. Some say over-diagnosis is diverting resources from seriously ill people to those with mild problems. Others say it’s better to catch the mild cases before they become serious.

IVF kids are taller and have more good cholesterol than naturally conceived kids. The height difference seems related to more growth hormones, not parental size. The study’s author thinks the difference is caused by IVF-induced genetic change, not by eugenics.

Robots are invading online poker. They never get tired or lose concentration, and your robot can make money for you while you sleep. But learning opponents’ behavior patterns is crucial in poker, and the best humans can still beat the best computers at that.

Genes affect monogamy in male prairie voles. Those with longer versions of a certain DNA segment show “increased probability of preferences for a familiar-partner female over a novel-stranger female.” Human DNA varies similarly, but nobody knows whether it affects human monogamy.

Asexuals are coming out of the closet. More than 4,000 have joined the Asexual Visibility and Education Network; an analysis last year indicated that 1 percent of British adults might be asexual. Some psychologists think asexuality is inherently dysfunctional; others classify it as “hypoactive sexual desire disorder” only if it causes distress.

Middle age is rising. In 2000, the average American was 35.3 years old, and remaining life expectancy from that point was 43.5 years. In 2050, demographers project the average American will be 41.7, but remaining life expectancy will be 2.3 years longer for that 41-year-old than it was for the 35-year-old in 2000.

Fingerprint scans are replacing credit cards at hundreds of stores. They’re faster and cheaper, and you don’t have to carry a card, though critics worry about privacy.

A study of twins found that orgasm difficulty in women is one-third genetic. Also, one in three respondents said she never or almost never achieves orgasm during intercourse. Consolations from the experts: 1) Less guilt and pressure. 2) Women don’t care as much about orgasms.

The first human product of an ovary transplant was born. The eggs came from the donor, but the donor’s DNA matches the birth mother’s because they’re identical twins. (Dutch doctors recently moved a woman’s ovary to her arm, where it “continued to produce an egg every month.”)

Half of Americans have been mentally ill at some point, and one in four has been mentally ill within the last year, according to the most thorough survey to date.

Bottlenose dolphins teach their children to use tools. They tear off bits of sponge and use them to probe for prey in sea grass. Researchers say the behavior is not genetic.

A poll suggests opposition to stem-cell research has grown among independents and Republicans. Since 2004, opposition in the WSJ/Harris online survey is up 7 points among Republicans and 4 points (8 points net) among independents.

Anthropologists argued that Jewish genetic diseases are the price of higher intelligence. The diseases emerged during the last millennium, when Ashkenazi Jews were forced by persecution into mentally demanding jobs. The hypothesis, which says acute natural selection of intelligence genes produced the diseases as byproducts, predicts  that people who carry the disease genes will excel at IQ tests.

Scientists made fruit flies gay by activating a single gene. Females with an activated “male” gene reject males and court females, while “males with a damaged version ignore females and sometimes try to mate with other males.”

Researchers report progress toward deriving embryonic stem cells without creating embryos. One method relies on nonlethal removal of embryonic cells before the stem-cell stage; another relies on fusion of an adult body cell with an embryonic stem cell.

A hormone nasal spray can make you trust other people with your money. The spray, prescribed for childbirth and nursing in Europe, doubled the percentage of study participants who entrusted all their money to an investment banker in a mock transaction. Critics think the danger isn’t that marketers will spray the hormone on you, but that they’re already using words, sounds, and images to trigger the hormone in your brain.

Senate Majority Leader Bill Frist proposed a “Manhattan Project” against bioterrorism. He cited a recent government report that “biological weapons are cheaper and easier to acquire than nuclear weapons—and they could be more deadly.”

President Bush ducked the question of regulating IVF. A reporter asked whether Bush’s rejection of the term “spare embryo” reflected a moral “view of fertility treatments that routinely create more embryos” than will be implanted or carried to term. Bush changed the subject to funding stem-cell research.

Massachusetts and Connecticut are rushing to catch California and South Korea in the stem-cell race. Connecticut lawmakers approved $100 million for stem-cell research. Massachusetts legislators, by overriding the governor’s veto, explicitly legalized therapeutic cloning.

The FDA says two dozen men who took pills for erectile dysfunction lost some eyesight. Skeptics think the vision loss is caused by the same vascular problems that cause erectile dysfunction.

Latest Human Nature columns: 1) Mandatory pregnancy: A true story. 2) Abortion and responsibility. 3) The coming war over IVF. 4) Bush’s hypocrisy on stem cells and the death penalty. 5) The evolution of creationism. 6) Why GPS tracking is good for felons. 7) Why pro-lifers fear the morning-after pill. 8) If steroids are cheating, why isn’t LASIK? 9) Jews vs. Catholics in the stem cell debate. 10) The case for raising the retirement age.