From bats to whales, the key to longevity is group living

From the Arctic whale to the bald mole, from the horseshoe bat to the golden rhinopithecus, group life seems to be one of the keys to longevity, limiting the risk of becoming prey or suffering from food shortages: this is indicated by a study done on nearly 1,000 species of mammals characterized by different social organizations, and with a life span ranging from 2 years for shrews to more than 200 years for some whales.

The research was published in the journal Nature Communications by a group of researchers led by the Beijing Zoology Institute, and will improve our understanding of the role played by these factors in evolution and their link with a longer life.

Researchers led by Pingfen Zhu and Weiqiang Liu analyzed 974 mammal species, comparing solitary, pair and group life with life expectancy.

Companion-loving species included the Asian and African elephant, ring-tailed lemur and mountain zebra, while the 'lone wolves' also included the dugong (a marine mammal), aardvark (a curious African insectivore) and the oriental squirrel.

The results show that those who live in groups generally enjoy a longer life: for example, the northern (solitary) shrew is similar in size to that of the horseshoe bat, but while the former has a short life of only 2 years, the the second can reach 30. The authors of the study also performed a genetic analysis on 94 of the species examined: they thus identified 31 genes and various hormones and other molecules which confirm the link between sociability and longevity.