Weight lessons from hunter-gatherers

As the obesity epidemic grows, one of the big debates is where the problem lies: our sedentary Western lifestyle, or our gluttonous Western diet? By monitoring a tribe of hunter-gatherers in Africa and comparing them to Western populations, a team of researchers discovered that humans generally burn about the same number of calories per day, regardless of what kind of society they live in. The stark conclusion: “Even dramatic differences in lifestyle may have a negligible effect,” and it’s diet that matters.

Pontzer, H. et al., “‘Hunter-Gatherer Energetics and Human Obesity,” PLoS ONE (July 2012).

Everyone loves a possible gold medalist

Whom would you advise the Red Sox to recruit: a rookie with a good shot to win Rookie of the Year, or a player who’s already won the award? According to researchers from Stanford and Harvard, you’re more likely to go for the rookie. In a series of experiments, people consistently preferred someone with the potential for a certain level of achievement over someone who had actually attained that level of achievement. The researchers even confirmed this phenomenon in a real ad campaign: Facebook ads that highlighted a comedian’s potential outperformed ads that highlighted the comedian’s achievement.

Tormala, Z. et al., “The Preference for Potential,” Journal of Personality and Social Psychology (forthcoming).

Same-sex benefits:
the profit case

When it comes to gay rights, the United States is a country in transition. For moral reasons, a company may well decide for or against offering same-sex partner benefits to its employees. But it turns out this decision also has financial implications: According to research from two professors of accounting at the University of Michigan, publicly traded companies that adopted same-sex partner benefits delivered “substantive and permanent improvements in firm value and operating performance” compared to similar companies that didn’t. These results didn’t seem to be explained by more successful companies being more likely to adopt benefits in the first place.

Li, F. & Nagar, V., “Diversity and Performance,” Management Science (forthcoming).

Smile, you’re low status!

You’re never fully dressed without a smile, the song goes—but whether you wear one may actually depend on how important you are. A new study finds that smiling is associated with lower status. In pictures, high-end fashion models and large football players displayed less smiling than low-end fashion models and small football players. Observers also seem to expect this pattern, as they reported seeing more smiling after being shown split-second pictures of fashion models from supposedly low-end brands.

Ketelaar, T. et al., “Smiles as Signals of Lower Status in Football Players and Fashion Models: Evidence that Smiles Are Associated with Lower Dominance and Lower Prestige,” Evolutionary Psychology (July 2012).

When equality helps
you survive

Given the military’s age-old embrace of an orderly hierarchy, you might imagine that this is the best social structure to protect soldiers’ lives, in good times and bad. But a new study by professors at Boston College suggests that in certain dire situations, your chances are better if you’re surrounded by equals. It turns out that American prisoners of war in World War II were less likely to survive if they were part of prisoner groups that were more hierarchical, because enforcement of the hierarchy made it harder for prisoners to trade necessities among themselves, with guards, and with the local population.

Holderness, C. & Pontiff, J., “Hierarchies and the Survival of Prisoners of War During World War II,” Management Science (forthcoming).