Food smells shorten flies' lifespan
Flies that hover around our food are a real nuisance, and unknown to them, they tend to live longer if they can?t smell food.Updated: Feb 05, 2007, 19:58 IST
Flies that hover around our food are a real nuisance, and unknown to them, they tend to live longer if they can’t smell food; no it has nothing to do with not getting swatted for hovering too close to our food.
A new research by Scott Pletcher of the Baylor College of Medicine, Houston, Texas, has revealed that fruitless can boost their lifespan by just not smelling their food.
According to the study, flies probably use their sense of smell as well as the actual consumption of food for determining how rich their environment is, and how they should go about distributing their energy resources.
Pletcher says the possible reason why animal fed on restricted diets generally live longer than those given abundant food, is that when there is little or less food, animals channelize more of their resources into maintaining their everyday body function.
For his study, Pletcher looked at mutant fruit-flies that did not have properly functioning smell receptors.
Findings revealed that fully fed flies without a sense of smell lived longer than normal flies on the same diet by 40 to 50 percent.
"We wanted to see whether we could use odour to trick the flies into thinking the environment was more nutrient-rich than it actually was. Normally, cutting a lab fly's usual food intake in half lengthens its lifespan by about 20 percent, from 41 to 50 days. But exposing hungry flies to the scrumptious smell of yeast, a favourite food, took away some of this benefit. About one-third of the beneficial effects on lifespan are lost," said Pletcher.
“It's difficult to tell what mechanism is at work. It is possible that, instead of the smell being an environmental signal, the yeast gives off some toxic substance that has a direct physiological effect on a fly that shortens its life,” said evolutionary biologist Daniel Promislow of the University of Georgia, Athens, who was not involved with the study.
The results are reported in the journal Science.