Aging is an unavoidable fact of life and one which science hasn’t fully explained but ecology Prof. Tom Sherratt is hoping dragonflies, damselflies and moths will help solve the mystery.
“If natural selection is so good at finding solutions to problems and optimizing, why is it that our bodies fall apart?” asks Sherratt, who has been studying insects as part of his research on aging. “If we can do something as miraculous as produce new offspring, why can’t we do something a little bit simpler and maintain what we already have?”
Sherratt began looking into the question with Robert Laird, who was then completing a post doctorate fellowship at Carleton and is now at the University of Lethbridge. They argue that aging happens when the physiological checks and balances that have evolved to protect individuals from environmental damage finally get stripped away. The reason that natural selection doesn’t protect people any further is that there is no point — organisms are likely to die from other causes anyway.
“If we’re going to be killed by a predator almost certainly by the age of 100, then it will protect us to the age of 100,” he explains. “Then there is no need to actually create any more protection for our bodily systems because so few individuals would ever live so long to use them.”
The insects are part of his research because Sherratt is trying to evaluate how and why damselflies and other species age in contrast to current thinking, which says that they die from other causes before they have a chance to get old.
“It has time and time again been suggested that aging does not occur in the wild — it only occurs in humans and animals domesticated by humans,” he says. Evidence disproving this long-held — and erroneous — belief has emerged in recent years and Sherratt hopes that his study will also uphold the belief that aging does, in fact, occur in the wild.
Next up is working with moths, in order to test the idea that some moths die soon after reproducing in order to protect their kin. The idea is that their presence can draw predators, harming other moths nearby. Sherratt and his graduate students are making artificial moths that they are placing outside, to see whether the presence of one moth increases the rate of attacks by predators on other moths. So far, they’ve found no evidence of this.
The natural question that emerges from research on aging is whether science can offer any solutions to help slow or stop the process. Sherratt says that although those in the scientific community are split regarding the question, he’s skeptical. “Science has shown some very, very clear ways to live longer and one of them is to eat less in a very balanced way.”
Sherratt doubts an anti-aging wonder drug will be developed in the future. “[Aging] is far too general a phenomenon … we can’t identify individual genes which are responsible for aging and do some gene therapy.”