An assortment of tree-living mammals
In The Descent of Man, Darwin talked about the benefits of life among the treetops, citing the "power of quickly climbing trees, so as to escape from enemies". Around 140 years later, these benefits have been confirmed by Milena Shattuck and Scott Williams from the University of Illinois.
By looking at 776 species of mammals, they have found that on average, tree-dwellers live longer than their similarly sized land-lubbing counterparts. Animals that spend only part of their time in trees have lifespans that either lie somewhere between the two extremes or cluster at one end. The pattern holds even when you focus on one group of mammals - the squirrels. At a given body size, squirrels that scamper across branches, like the familiar greys, tend to live longer than those that burrow underground, like prairie dogs.
These results are a good fit for what we ...
