Discovered: Babies are very calculating; political turmoil affects HIV treatment; another Earth is out there, probably; gender stereotypes affect the advancement of women in science.

Babies like people who injure babies not like them. It's no secret that infants like people who are nice to them — usually their parents, and maybe their playmates, too. But according to several American researchers, babies also like people who harm or otherwise injure babies who are somehow unlike them — i.e., babies who like different kinds of food than they do. To be sure, such behavior is found among adults — the enemy of your enemy is your friend, and all that. But who knew that babies were so calculating, too? As one of the researchers in a new study explained, "The fact that infants show these social biases before they can even speak suggests that the biases aren’t solely the result of experiencing a divided social world, but are based in part on basic aspects of human social evaluation." [Psychological Science]

Political turmoil affects HIV treatment. Treating HIV in the developing world is difficult for a lot of reasons — a lack of access to contraception among them — but rarely is the political climate figured into treatment research. But scientists at Brown University now insist that political strife can attenuate the efficacy of HIV treatment: "When violence erupts, staying on ... delicately balanced medications can become impossible. Drugs may no longer get to the clinic, patients and health care workers can become displaced, travel to the clinic can become unsafe, and patients can become profoundly depressed by the horror and tragedy around them." All the more reason to avoid violence whenever possible: "If political leaders and their opponents happen to need one more reason to forgo violence, they can consider how it appears to worsen the HIV pandemic among their constituents." [AIDS Reviews]

Another Earth is out there, probably. We know that there exist other planets which, like Planet Earth, are capable of supporting life. But until now we weren't quite sure how many of them there were in the universe. Just within ten light years, a Penn State geoscientist says, there "about four" Earth-sized planets in the habitable zones — "a region around a star where rocky planets are capable of sustaining liquid water and therefore life" — of the 10 nearest small stars. The geoscientist went straight to the point in explaining the application of his research: "There are nearly three times as many Earth-sized planets in the habitable zones around these low mass stars as in previous estimates [which] means Earth-sized planets are more common than we thought, and that is a good sign for detecting extraterrestrial life." [Astrophysical Journal Letters]

Gender stereotypes affect advancement of women in science. We like to think of science as coolly rational, unaffected by cognitive shortcuts like stereotypes. But according to three American researchers, women with careers in commercial science are often impeded by stereotypes about their gender. "Female professors are almost 50 percent less likely than their male counterparts to be invited to join corporate scientific advisory boards (SABs) and start new companies mainly because of gender stereotyping," their study found, citing belief that "women lack leadership and business savvy" and that women "are not capable of helping new ventures attract investment." Academia, they argue, can help level the field: "University scientists have helped create at least half of the publicly traded biotech firms operating today, and a female professor is most likely to draw a science advisory board invitation by tapping into her school's technology transfer office." [Academy of Management Journal]