Why are physically attractive people more intelligent than others, on average?

Research has shown that people who are regarded as physically attractive also tend to be seen as more intelligent. And it has often been noted that attractive children tend to receive higher grades in school. Although the later finding has been interpreted as evidence of teacher bias, an economic analysis of the informal market for marriage partners suggests that better-looking children may actually e smarter. Evolutionary psychologists Satoshi Kanazawa and Jody Kovar, for e.g. offer persuasive evidence for the following four propositions:

1) More intelligent men tend to achieve higher social status and higher incomes.

2) Men generally regard physically attractive women more desirable for marriage partners

3) Women generally regard men with higher incomes and higher social status as more desirable marriage partners.

4) Both intelligence and physical attractiveness are traits with significant heritable components.

If the first three propositions are true, then it follows logically that relative attractive women will pair up disproportionately with relatively intelligent men. And if both beauty and intelligence are heritable, then the offspring of such unions will tend to display above-average value of both traits. In short… the hypothesis that beauty and rains go together does not appear far-fetched

Why are whales in danger of extinction, but not chickens?

Seldom does a year pass without street demonstration by environmental activists decrying international hunting that threatens extinctions for many large marine mammals’ species. Yet to my knowledge there has never been a demonstration exhorting us to save chickens. Why not? The short answer is that chickens have never been an endangered species. But that just raises the question of why one species is endangered and another not. Whales’ populations have been dwindling because no one owns whales. They swim in international waters, and several nations have refused to respect the international treaties that have attempted to protect them. Japanese’s and Norwegian whalers understand perfectly well that their current practices threaten the survival of whales and hence their own livelihood. But each whaler also knows that any whale he does not harvest will be taken y someone else. Thus no whaler stands to gain from self-restraint. In contrast, most chickens in the world are owned by someone. If you kill one of your chickens today, that is one less chicken you own tomorrow. If chicken farming were your livelihood, you would have strong incentives to balance the number of birds you send to the market and the number of chicks you would acquire. Chickens and whales are both economically valuable. The fact that people enjoy secure property rights in chickens but not in whales explains why the former are secure and the latter are endangered.

Why are DVD’s sold in much larger packages than CD’s, even though the two types of discs are exactly the same size?

CD’s come in cases that are 148 milimeters wide and 125 milimeters high. In contrast, DVD’s are sold in cases that are 104.5 milimeters wide and 191 milimeters high. A little digging reveals the historical origins of this difference. Prior to the appearance of digital CDs, most music was sold on vinyl discs, which were packaged in close-fitting sleeves that measured 302 millimeters square. The racks on which vinyl discs were displayed were just wide enough, in other words, to accommodate two rows of cases with a divider between them. Making the CD cases a little less than half as wide as the album sleeves they were replacing thus enabled retailers to avoid the substantial costs of replacing their storage and display racks. Similar considerations seem to have driven the decision regarding DVD packaging. Before DVDs became popular, most film rental stores carried videotapes in the VHS format, which were packaged in form-fitting boxes that measured 135 millimeters wide and 191 millimeters high. These videos were typically displayed side by side with their spines out. Making DVD cases the same height enabled stores to display their new DVD stocks on existing shelves while consumers were in the process of switching over to the new format. Making the DVD package the same height as the VHS package also made switching the DVDs more attractive for consumers, since they could store their new DVDs on the same shelves they used for their VHS tapes