We talk to expert João Pedro de Magalhães about animal ageing
What fascinates you about ageing and longevity?
I decided early to work on ageing because I’m afraid to die, and ageing is directly or indirectly the major reason people die in modern societies. So my motivation was to solve what I see as the greatest cause of suffering and death. In addition, even though ageing affects the majority of people, it remains a mystery in that we still don’t understand at the mechanistic level why humans age, or why longevity varies across species.
Why do we think some creatures live longer?
We don’t understand yet why there are differences in the longevity between species, including between very similar species like chimpanzees and humans. There’s evidence that animals that have a lower body temperature live longer, so some of the longest-lived animals in the world, like the ocean quahog clam, live in very cold waters. From an evolutionary perspective, we also understand that animals that live very long need to be protected from predators (such as by flying or living on predator-free islands), and conversely animals that suffer a lot of predation need to grow and reproduce very quickly.
How do you determine the age of wild animals?
It’s quite a difficult process, and it depends on the species. For bowhead whales, for example, researchers quantified biochemical changes in the eye lenses. These are not very accurate methods, however, so we may well be overestimating or underestimating the longevity of many species.
What are some of the most exciting recent discoveries in your field?
The discovery that the Greenland shark can live for nearly 400 years has been very exciting because it’s the longest-lived vertebrate. I think the other revolution is at the level of DNA sequencing, in that we can now sequence the genome of any species quickly and cheaply.
Tell us about the AnAge project
I’ve always loved animals and wanted to understand differences in longevity. I started the AnAge database of ageing longevity in animals when I was a PhD student. It started as a way of keeping track of records, and now we have over 4,000 species. It’s useful for scientists to study the evolution of longevity and which factors correlate with longevity. It has been cited hundreds of times and is a major tool for researchers and the public.
Can humans learn the secret of long life from animals?
Absolutely. My hypothesis is that different animals use different tricks to live longer, and if we can unravel those tricks we may then use that knowledge to allow people to live longer, healthier lives. For example, if there are particular mutations in long-lived animals that confer longevity or disease resistance, we may be able to develop drugs that mimic the benefits of those new mutations so we can all benefit.