Biologists finally horn in on senescence in the wild.

In 1995, biologists discovered an unusual new species, the antler fly (Protophila litigata). Antler flies inhabit discarded moose and deer antlers for most of their life cycle, and male antler flies exhibit sexually selected behaviors on their home antlers. It now turns out that these curious flies might provide new insights into the evolution of aging. For years, biologists assumed that senescence did not occur in the wild. But over the past decade, several studies of natural populations of birds and mammals have found age-related declines in rates of reproduction or survival, indicating senescence. A new study of antler flies by Bonduriansky and Brassil provides the first evidence for senescence in a wild invertebrate. The researchers are able to mark individual flies and follow them throughout their entire, albeit short, life-spans. This small species offers huge opportunities to study senescence and age-related selection on fitness characters in the wild.