“Until now it has been difficult to estimate lifespan for most wild animals, particularly long-living species of marine mammals and fish.” - Dr Ben Mayne, CSIRO.

Findings could prove beneficial for conservation

Researchers at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) have developed a new method to estimate the lifespan of a species.

The discovery will greatly improve conservation and wildlife management, which has previously relied on observing the life span of wild animals. The natural human lifespan was found to be 38 years, matching estimates for early modern humans. This has of course been extended by medical advancements and lifestyle changes.

Postdoctoral fellow with CSIRO’s Environomics Future Science Platform Dr Ben Mayne said: “Our method for estimating maximum natural lifespan is based on DNA. If a species’ genome sequence is known, we can estimate its lifespan.

“Until now it has been difficult to estimate lifespan for most wild animals, particularly long-living species of marine mammals and fish.”

According to a statement, the researchers used genomes of animals with known lifespans from public databases, such as the Animal Ageing and Longevity Database, to calibrate their method.

Researchers were also able to uncover the lifespan of extinct species, such as the wooly mammoth (60 years) through assembling a new genome from that of the modern African elephant.

Dr Mayne continues: “There are many genes linked to lifespan, but differences in the DNA sequences of those genes doesn’t seem to explain differences in lifespan between different species.

“Instead, we think that the density of a special type of DNA change, called DNA methylation, determines maximum natural lifespan in vertebrates.

“DNA methylation does not change a gene’s sequence but helps control whether and when it is switched on.

“Using the known lifespans of 252 different vertebrate species, we were able to accurately predict lifespan from the density of DNA methylation occurring within 42 different genes.

“These genes are likely to be good targets for studying ageing, which is of huge biomedical and ecological significance.”