Category: Science

On Taiwan, abortions have skewed the island’s demographics to the point that only two girls are born for every three boys.

For the full story, along with a Darwinian analysis, read here.

I vote for the gorilla, which in fact took first prize.

Here is Steve Landsburg’s follow-up column, from Slate.com, it includes an excellent summary of the original debate as to whether daughters cause divorces.

The bottom line: Landsburg argues convincingly that divorce really is more common when parents have a daughter, rather than a son. Now here is Steve’s new explanation for this fact:

Suppose parents believe that inherited wealth is more important to a boy than to a girl–either because wealth gives boys a bigger advantage in the mating competition or because boys are more likely to do something entrepreneurial. Then parents of boys will try harder than parents of girls to preserve their wealth. In particular: 1) Parents of boys will avoid divorce, because divorce is costly; and 2) parents of boys will have fewer children, because extra children dilute the inheritance.

My take: I still think that most parents, especially fathers, simply prefer boys, whether they admit it or not. But like Steve, I consider myself an exception to this principle!

Some people find this objectionable but I am in favor of experimentation.

The nocebo effect arises when you expect a poor health outcome, and then get one. For obvious reasons, nocebo effects are harder to test scientifically, because researchers do not wish to create them on purpose.

Robert Ehrlich, in his Eight Preposterous Propositions, reports a few experiments. A group of hospital patients were given sugar water, and were told it would induce vomiting. Eighty percent of the patients vomited as a result.

Many Chinese and Japanese people believe that the number four is unlucky. Scientists studied a sample of 200,000 such people, living in America. On the fourth day of the month, the death rate from heart attacks was thirteen percent higher.. In California, where Asian population concentrations might reinforce superstitious beliefs, the death rate on the fourth was twenty-seven percent higher. I wonder how many of the “heat deaths” in Europe were accelerated, simply because some people thought they were supposed to be dying.

Additional notation: The machine I am working on won’t do “Cut and paste” for links, among other things, nor will it do boldface. You can track down the Ehrlich book through Amazon.com or my previous posts on placebos.

OK, a big meteorite falls through your roof and wrecks part of your house. Are you worried? Maybe. Are you rich? Well, maybe yes. Exactly this happened to one family in New Orleans.

“They’re extremely lucky,” said Rhian Jones, curator of meteorites at the Institute of Meteoritics, with a note of envy creeping into her voice. “It’s so rare and such an amazing thing to happen. They were lucky they weren’t in the house at the time, but they were lucky that it happened. It makes them very special.”

One dealer estimated that the meteorite could sell for $8 to $20 a gram, or somewhere between $108,862 and $272,156. If it had been from the moon or Mars, it would have been worth millions. The damage to the house was estimated at $10,000. The family will now take that long-awaited European vacation.

Meteorite dealing has boomed in the last decade, in part because of the Internet, and in part because of new supply extracted from the Sahara and Antarctica. Here is one reputable place to buy a meteorite. Here is an ebay listing, 759 items when I checked, although most of them are cheapies. Note that a quality meteorite collection can be worth several million dollars.

For the full story of the “victimized” family, click here. It remains to be seen whether insurance will cover the damage to the house. After all, are meteorites not the proverbial “act of God”?

Placebos have been shown to be quite effective in treating skin warts, which are clearly not a subjective ailment and are caused by viruses. According to an Australian physician, F.E. Anderson, warts probably have the highest number of folk remedies of any disease, which is not surprising if they respond well to placebos.

From the excellent Eight Preposterous Propositions, by Robert Ehrlich.

Francis Bacon recommended treating warts with pig fat. Sometimes warts respond well to hypnotic suggestion, an effect which is not well understood. And this is from an author strongly opposed to pseudo-science.

Read here. Here is a short bit on the scientific developments behind cheap corn. I wouldn’t want to take any of these developments back, as they have saved millions of lives around the world. Nonetheless the biological/behavioral arguments for market failure are growing in importance (human beings did not evolve to handle fully abundant fats and sugars), relative to the traditional externalities arguments. If you don’t believe me, check back in thirty years.

Old ideas that REM sleep deprivation led to insanity have been convincingly disproved…

Now I hope this second part was not funded by government money:

…although studies show that depriving someone of sleep, for example by prodding him or her awake repeatedly, can definitely cause irritability…

What else did I learn?

Body size appears to be a major determinant in the amount of sleep that a species needs. In general, the larger the animal, the less sleep it requires. Data suggest that one of the functions of sleep is to repair damage to brain cells. The higher metabolic rates of small animals lead to increased cellular injury and may, consequently, require more time for repair.

Opossums sleep eighteen hours a day, elephants three.

From the November issue of Scientific American, the article, “Why We Sleep,” is not yet on-line.

When a country experiences a dramatic, faltering economy, there is an equally dramatic, faltering effect on the birth rate. Specifically, there are more female births than male births, according to new research from the University of California, Berkeley. Although this phenomenon has long been observed in herd animals, this is the first time it’s been shown to happen in humans, too.

Here is the full article. Here is a press release from Berkeley. Here is Ralph Catalano’s [the researcher] home page. Here is the article itself, but the whole thing will cost you $19.00.

By the way, here is another puzzle: more boys are born in southern Europe than in northern Europe. More females are born in Mexico. Could this all correspond to stress? Here is another study, it says that stressed out parents are more likely to have girls.

My take: I can believe the result, but I haven’t much raised my priors. Note that the spike in East German female births comes in 1991, when the East German economy collapses. OK, we have found some related results elsewhere, and for other animals, that counts for a good bit in my eyes. Nonetheless I am reminded of Brad DeLong’s excellent article Are all Economic Hypotheses False?”, with Kevin Lang. If you spend enough time looking, and there is publication bias, some results will pop up, whether they are true or not. The cynical would say that behind this article, as described in the press releases, there is really only a single data point, namely 1991. N.B.: I haven’t paid the $19 to read the article itself, final judgment is reserved for those who pay and read.

Addendum: Jon Klick read the piece and sent me the following:

You’re exactly right that you’re really only focusing on one data point to identify the hypothesized effect. One wonders why he didn’t include the GDP numbers directly rather than simply including a “collapse” variable. Doing so would have allowed for more variation. If the claim is endogeneity (isn’t it always), then that’s not really solved through the collapse variable since it would be endogenous too. Also, isn’t it kind of funny how he uses a 55 year pre-period relative to an 8 year post period. If the ARIMA structure went through any significant changes around the 1991 period, you would be implicitly weighting your early data (and their ARIMA parameters) more heavily than the potentially new parameters. Thus, the 1991 change could be due to these structural parameters rather than anything GDP related; impossible to sort the effect in this design.

…[it] potentially suffers from huge omitted variable bias. That said, there are intuitive reasons to believe the thrust. Apparently, boys are more expensive in every way during the early years of life (e.g., they have more health problems which cause financial and physical drains on parents . . . this shows up in the evidence that mothers of boys die earlier and the like). Presumably then, the reproductive system has developed such that boys are spontaneously aborted when their births are likely to be most troublesome (e.g., when economic and psychological stresses are particularly acute).

Chris Mooney says yes. Here is his bottom line:

In 1995, a budget-cutting Republican Congress fired its science advisers for being too politicized and too slow. In an age of bioterror, climate change, and high-tech weaponry, we need them back.

I’d like to return to this topic in the future, and the general question of whether pure science deserves government subsidy, but here is the link while it is hot.

Here are some views that declined in popularity from 1925 to 1950. The first number is the percentage of people who believed the claim in 1925, the second number is the percentage from 1950:

1. Long, slender hands show an artistic nature: 42.0, 6.4

2. Adults can become feeble-minded from overstudy: 56.0, 10.9

3. You can closely judge a person’s IQ from his face: 50.0, 3.6

4. Women are by nature purer and better than men: 38.0, 1.8

5. The position of planets affects your character 15.0, 6.4

6. Expectant mothers can affect the character of unborn children by thought: 38.0, 2.7

From Robert Ehrlich’s Eight Preposterous Propositions: From the Genetics of Homosexuality to the Benefits of Global Warming. I’ll be blogging more about this interesting book soon.

Those six views are, of course, all preposterous. But if I had to defend one of these in a debate, I would opt for number three. Number six would come next, then number four. Number five is totally stupid, but in a way we have grown to expect. So number one seems the craziest to me.