1. Brazilians, more European than not? This blog post summarizes a recent genetic study of the ancestral background of Brazilians from different regions of the country: “black Brazilians have a much higher load of European ancestry than black Americans, while white Brazilians have a much higher load of Amerindian and African, than white Americans.”

2. Religious fundamentalism is in the genes. This summarizes a study done to compare identical and fraternal twins to examine how much of the subjects’ religious personality characteristics are determined by genetics, the home environment, and the external environment. For childhood religiosity, “[t]he biggest factor is your family, and not your genetics. It’s not until adulthood that the effects of genetics really start to shine through.” The “importance of religion in your life is about one-quarter defined by genetics, as is your spirituality. The most important factor here, however, is the external environment.” Same for religious attendance. “There are three factors that are about 40% driven by genetics, with your family upbringing having hardly any effect. These factors are: how often you turn to religion for guidance, whether or not you take the bible literally, and whether people should stick to one faith, or experiment with others. . . . But the big finding in this study is the born-again religious. These are the people who answered ‘yes’ to the question: ‘Have you been ‘born-again,’ that is, had a turning point in your life when you committed yourself to Jesus Christ?’ A whopping 65% of this kind of religiosity is genetically driven!”

3. Does religion lead to a healthier society? They compare the correlation of various negative behaviors (homicides, abortions, teen pregnancies) in different countries, and the levels of religiosity in those countries. They find a positive relationship between the bad behaviors and religiosity (meaning that there is more bad behavior in countries that are more religious). I don’t think their results are very convincing to prove that religion has any sort of negative effect (in their defense, they acknowledge that their results are preliminary and do not prove causation). Three problems: first, they don’t adjust for the different demographic characteristics of the countries (for example, people who have more education tend to be less religious, but also tend to engage less in many sorts of negative behaviors; there are several other similarly relevant demographic characteristics that need to be controlled for). Second, even if the relationship is still there after the relevant factors have been controlled for, it doesn’t tell us about causation (it could be that crime causes more religiosity as people seek in violent societies seek solace and and a sense of community from their local churches). Third, by other measures, the United States (which stands out as the most religious developed country) does better than the less-religious countries. For example, even though U.S. Murder rates are high, overall violent crime rates are lower than they are in many European countries. People in many religious countries also appear to be more charitable than they are in less religious countries (giving more money, volunteering more time to charities, and offering help to strangers).

4. How Humans Got Spineless Penises and Big Brains. Two things (among others) that make humans unique from our chimpanzee cousins is that our brains are bigger and human penises lack spines (most male mammals have spiny penises). A comparison of the human and chimpanzee indicates that some specific deletions from our genome led to these changes (and that neanderthals had these same deletions).