From Science:
In elephant society, nothing is more important than family. From traveling packs of mothers and calves to larger groups that contain aunts and cousins, all segments of the creature's complex social structure are typically composed of relatives. But what happens when these populations are decimated by humans? New research reveals that elephants sometimes bring in non-kin to keep their social groups viable. The finding is based on a survey of about 400 elephants living in Kenya's Samburu National Reserve. The elephants are part of a larger population that lost three-quarters of its members to ivory poachers in the 1970s. Today, the group remains vulnerable to illegal killing by nomadic tribes, farmers, and others. Curious about how such devastation has affected the social structure of the Samburu elephants, conservation biologist George Wittemyer of Colorado State University in Fort Collins and colleagues studied the creatures for 5 years. They pinpointed the elephants' genetic relationships to each other by sequencing DNA from fresh dung samples. The researchers found that when they looked at the largest groupings of elephants in this society–so-called “clan” and “bond” groups–many of the elephants had opened up to include nonrelatives.
More here.
