Bowhead whales can live for 268 years, shows new Lifespan Clock that can predict how long an animal will live based on its DNA
A bowhead whale born today may roam the oceans for 268 years, suggests a new study.
Scientists arrived at this estimate, after developing the first Lifespan Clock — a technique that can predict the natural lifetime of animals by examining their DNA.
With the help of this technique, scientists found that the initial estimate of Bowhead whale lifespans may have been wrong. It was earlier believed that they may live up to 200 years.
"Knowing the lifespan of wild animals is fundamental for wildlife management and conservation," writes Dr. Benjamin Mayne from the Commonwealth Scientific and Industrial Research Organisation, Crawley, in The Conversation.
Scientists could use this information to conserve endangered species and dictate catch limits for sustainable fishing. Until now, scientists have not been entirely successful in determining the lifespan of most animals.
"Most estimates come from a small number of individuals living in captivity whose ages at death were known. For long-living species it is difficult to obtain a lifespan as they may outlive a generation of researchers," writes Mayne.
Hence, Mayne and his colleagues turned to DNA. "DNA is the blueprint of living organisms and it is an obvious place to seek insights into aging and lifespan. However, no-one has been able to find differences in DNA sequences that account for differences in lifespans," says Mayne.
They tracked changes in the status of DNA methylation, which can determine the age of an animal. "Despite DNA methylation being linked to aging and lifespan, no research until now has used it as a method to estimate the lifespan of animals DNA," he adds.
The technique can be used to determine the lifespan of extinct animals as well. For instance, the extinct Pinta Island giant tortoise was believed to live for over 100 years.
The lifespan clock estimated the maximum lifespan of the Pinta Island tortoise to be 120 years old, indicating that their lifespan was underestimated.
Humans, on the other hand, are outliers. When they applied the technique to humans, they found that humans have a natural lifespan of 38 years. But humans today enjoy longer lives, thanks to advances in medicine and lifestyle that have extended the average lifespan.
"As more scientists assemble the genomes of other animals, our method means their lifespans can readily be estimated. This has huge ecological and conservation significance for many species which require better wildlife management," he says.