"Aging - or senescence - has been seen under controlled conditions in the lab, but never before in insects living in their naturally evolved habitat," says University of Toronto zoology doctoral candidate Russell Bonduriansky. "Our study of antler flies shows these animals do age in the wild."
Bonduriansky and co-researcher Chad Brassil, both of the evolutionary ecology group at U of T, studied male antler flies to see if there was aging - a term used to denote a deterioration of the body's vital functions, not chronological time. The two zoologists examined the flies to see if their abilities to survive to the next day and to mate deteriorated with age. The study appears in the Nov. 28 issue of Nature.
"We found that the flies deteriorate over their lives. As they get chronologically older, their chances of dying by the next day increase," says Bonduriansky. "While their probability of death increased, their probability of mating decreased. A decrease in both survival and reproduction unambiguously demonstrates aging."
An important feature of the study was the flies' natural environment, says Brassil. "When you study flies in the lab, they live for a long time because they don't have any predators or risks. Eventually, however, they do start to deteriorate. Now we have shown that this deterioration also occurs in the wild."
In Ontario's Algonquin Park, the researchers studied several hundred antler flies, an insect that breeds exclusively on the discarded antlers of moose and deer. The insects' relatively small geographical domain enabled the team to mark and track the progress of individual flies throughout their lives. "We had a small number of moose antlers in the field so we knew we were looking at the whole system. We were able to follow the flies throughout their lives - a very rare occurrence in nature where insects ch
Contact: Lanna Crucefix
University of Toronto