Sharing is one of the hallmarks of human behavior : give me a cookie and I'm more likely to give you one later. But our bonobo cousins have an odd variation on the practice. They share with strangers before friends. The finding is in the journal PLoS ONE. Researchers tested bonobo sharing in experiments involving fourteen of the apes. All were born in the wild. In the primary experiment, bonobos were placed in a cage with food, and they could choose to admit either a known member of their group, a stranger, or both. In 51 trials, most bonobos shared the feast, but they let the stranger in first. Why choose an outsider over a friend? In another experiment, the scientists found bonobos only shared when doing so led to a social interaction . Giving up some food to strangers lets these apes expand their social network. This behavior may have evolved to promote social tolerance, in contrast with chimps' sometimes deadly aggression against strangers. Which means that even when food is offered , there's still no such thing as a free lunch

A lot of people just don't feel quite human without that morning cup of coffee. Now a study finds that the enhanced sense of well-being that caffeine can cause is reflected in our perception of words. Specifically, caffeine increases the ability to recognize words associated with positive thoughts, but doesn't provide the same boost for words with negative or even neutral associations. The research is in the journal PLoS One. Scientists assigned 66 subjects to one of two groups. Half got a 200-milligram caffeine tablet, a dose equal to almost three cups of coffee. The other half received a sugar tablet. Thirty minutes later the volunteers were shown strings of letters, and had to decide as fast as they could if a string formed a word or was just gibberish. The volunteers recognized words with positive associations much faster than either negative or neutral words. Other studies have shown that positive words tend to be recognized more quickly, but the caffeine increases the gap. So next time you wake up with a grumpy sweetheart, your compliments might be appreciated more if they have a cup of coffee first

Advertising and media companies often get lobbied to use models that ......represent.... the average woman's body— rather than ultra-thin models, whose images may influence some women to have an unhealthy ....relationship.... with food. Now a study supports that idea that observed images affect what people consider to be acceptable body types. The report is in the journal PLoS ONE. Researchers surveyed subjects about their ....opinions... of their own bodies and those of others. Then they presented the subjects with photos of large or thin women. Some photos were of beauty queens in evening gowns or other high-status clothing. Other photos were of women who were either very large or very thin, .....wearing.... neutral grey leotards. Following those viewings, the subjects were again surveyed about their body preferences. Subjects who originally preferred thin bodies only increased their preference for thinness after being shown photos of thin women. But they .....decreased.... their preference for thin bodies after being shown photos of larger women. And the attire of the women in the photos made no difference to the subject's latter preference.The researchers say that this study provides strong evidence that images of female bodies .....promoted..... by the media and ad agencies could have a real .....impact..... on women's preference and subsequent thoughts about body type