How chimps craft lethal weapons.

Science, technology, and life.
Feb. 23 2007 9:19 AM

Planning of the Apes

How chimps craft lethal weapons.

(For the latest columns on pain weapons, gay sheep, and shrinking people, click here.)

Chimps have learned to craft hunting weapons. Their method: break off a branch, "strip it of leaves and twigs, trim it down," "chew the ends to a point," and "use it to stab into holes where bush babies might be sleeping." A researcher who observed the stabbing says it looked like the shower scene in Psycho. Theories: 1) We're not the only animals with this level of lethal sophistication. 2) This group of chimps lives in a particularly harsh place, so its weapon-making innovation was forced by circumstances, suggesting that the same thing happened to early humans. 3) Females and juveniles do the spear-hunting, so maybe ev-psych notions of male brutality and female docility are wrong. 4) Females make and use the weapons because pregnancy, child supervision, and inferior size force them to—in other words, the same adversity that makes humans superior to other animals at innovation also makes females superior to males. (For Human Nature's take on the convergence of weapons development with moral development, click here.)

William Saletan William Saletan

Will Saletan writes about politics, science, technology, and other stuff for Slate. He’s the author of Bearing Right. Follow him on Twitter.

Breastfed kids become better social climbers. A study with a 60-year follow-up says they're "41 percent more likely to move up at least one social class during their lives." The study defines class mobility based on your dad's occupation and, later, yours. Breastfeeding makes a small difference even within the same family. Approved theories: 1) Breastfeeding helps brain development and therefore IQ. 2) It makes you physically healthier. 3) It makes you emotionally healthier. 4) Moms who breastfeed are smarter, so their kids have other genetic or environmental advantages. Unapproved theory: Breastfed kids are better at finding teats. (For previous updates on breastfeeding and alcoholism, click here and here.)

Terrorism has erupted in a huge, online fantasy world. Membership in Second Life has soared from 100,000 to 2 million in a year. Freeloaders and corporations selling real stuff are coming in; imaginary elves are leaving. The company that runs the world says it needs corporate money to keep it growing and going. Some old-timers, angry at the changes, stratification, and limits on democracy, have formed the "Second Life Liberation Army" and are virtually shooting people and detonating bombs outside chain stores to generate real publicity. Liberation Army's spin: We're like the American revolutionaries. Left-wing view: Everything started going to hell when the corporations came in. Right-wing view: Everything started going to hell when the terrorists came in. Human Nature's view: Everything started going to hell when the people came in. (For previous updates on virtual sex, virtual offices, and real money, click here, here, and here. For Human Nature's take on prosecuting cybersex, click here.)

Europeans are pushing to ban smoking in cars. The German government is considering it, and the Irish lobby that pushed through the first nationwide ban on indoor smoking has targeted cars. Rationales: 1) We've already agreed that smoking should be banned indoors because it's particularly harmful in tight spaces. 2) Cars are very tight spaces. 3) Libertarian arguments don't apply, because passive smoke harms other passengers, including kids. 4) "If it is not safe to hold a mobile phone while driving—it's difficult to see how it can be safe to smoke." Objection: Your home is a tight space, too. Is that next? (For previous updates on car smoking bans in Arkansas, Maine, and New Zealand, click here, here, and here.)

A drug company will stop lobbying states to vaccinate all girls againsta sexually transmitted virus. The company, Merck, was under fire for using third-party groups to push its lucrative vaccine on lawmakers.The virus, known as HPV, causes cervical cancer. Conservative arguments against the vaccine mandate: 1) It usurps parental authority. 2) It encourages promiscuity. 3) It's unnecessary, since you can't catch the virus just from being in school, as you can with measles. Liberal arguments against it: 1) At $360 a pop, it's too expensive. 2) It's too new to be declared safe enough to mandate. 3) Other diseases are more urgent. Merck's spin: We'll stop the lobbying, since it has become a "distraction" from our noble goals. Cynical translation: We'll stop the lobbying, since it has been exposed. (For a previous update on the HPV vaccine, click here.)

Malaysia is considering a ban on fast food ads. The government is also contemplating a "sin tax" on fast food. Rationale: Junky meals have become "silent killers," making Malaysians fat, diabetic, and hypertensive. Health minister's spin: "We do not allow advertising for cigarettes and liquor. … Fast food should be treated in the same way as alcohol." Response from Malaysian ad industry: Even the crazy Americans haven't gone this far. (For Human Nature's takes on regulating fast food, click here, here, and here.)

The record for gestational age of a surviving baby has been broken again. New record: 21 weeks and 6 days (5 months). The baby was 9.5 inches long and weighed 10 ounces. After four months of round-the-clock intensive care, she's finally well enough to go home. A national registry shows no other surviving babies born before 23 weeks. The American Association of Pediatrics says a baby born at 21 weeks or weighing less than a pound is not viable. Pro-life spin: Thanks to IVF, we can verify this baby's gestational age and prove that the viability line has advanced. Anti-choice spin: Thanks to IVF, this pregnancy was imposed on a body naturally unfit for it, resulting in a tortured pregnancy, a horribly early birth, and a disastrous four-month drain on hospital resources.  (For Human Nature's previous take on fetal pain at 20 weeks and beyond, click here.)

India is offering to raise baby girls so couples will stop aborting them. Problem: Sex-selective abortions have wiped out millions of fetuses and skewed the population. Proposed solution: Nationally funded orphanages. Government minister's message to couples: "If you don't want a girl child, leave her to us … [D]on't kill them because there really is a crisis situation." Cynical translation: We didn't care about these abortions till they became a demographic problem. (For previous updates on sex selection of embryos and fetuses, click here, here, and here.)

Latest Human Nature columns: 1) The future of pain-beaming weapons. 2)  Gay sheep and human destiny. 3)  More on gay sheep. 4) The power to shrink human beings. 5) The first human embryo factory. 6) The bum rap on cloned food. 7) Lesbians of mass destruction. 8) The Best of Human Nature 2006. 9) Food and sex without consequences.