Than Males Diet can change the rate of aging in fruit flies, even reversing the normal longevity advantage of females over males, according to a population study by researchers at the University of California, Davis. The results support earlier findings by the same scientists indicating that life span is not necessarily fixed for all animals, as had been presumed for years by many gerontologists. Fast-breeding Medflies are used as models to study basic population questions. The newly published study provides a statistical analysis of the life span of more than 400,000 Mediterranean fruit flies.
Medflies usually live for about two to three weeks.
Those that make it to 60 days have lived the equivalent of 85 human years. If they receive a normal diet of sugar plus protein, females generally outlive males by about 1.5 days. But in this new study, the researchers report that, when fed a protein-deprived diet, males lived shorter lives overall, but outlived females by a little more than two days. Carey and colleagues conducted this nutrition-manipulation study to determine why death rates level off sooner and at a lower level for female Medflies than for their male counterparts. That project used 1.2 million Mediterranean fruit flies to produce the largest mortality study of any non-human species and provided powerful evidence that longevity is not genetically fixed for a species, but can be environmentally extended.