The Strange Biology of the Fish That Lives for a Century

And this slow-aging process is common in other long-living creatures. "Long-lived species characterized by slow life history and relatively low fecundity are known to be extremely vulnerable to perturbations of a natural or anthropic nature due to their very low replacement rate," explained Mahé, in the release. One reason humans age has to do with DNA replication. Telomeres are "caps" at the end of every strand of DNA that protect our chromosomes, not unlike bottle caps or the plastic tips on shoelaces' ends, and they're a vital part of human cells. Much like shoelaces, without this "cap," the DNA strands accrue damage and reduce the effectiveness of cells.

Every time a human cell copies itself, the telomeres deplete. So naturally, one idea of prolonging or extending life involves slowing the decay of our telomeres, and thus reducing the rate of decay for our DNA. The recent study didn't investigate coelacanth DNA, instead concerning itself with external evidence of age, analyzing the circuli on the creatures' scales. "We demonstrated that these circuli were actually annual growth marks, whereas the previously observed macro-circuli were not," said Mahé. "It meant that the maximum longevity of coelacanth was five times longer than previously thought, hence around a century." But it stands to reason that an underlying biological factor in the unusually long lifespan of the creatures could involve its telomeres.

The coelacanth species' aging process might be affected by climate change

For now, the researchers emphasized the acute implications of their findings on conservation efforts for the coelacanth. According to the researchers, the African coelacanth is regarded as critically endangered, on the IUCN's Red List of Threatened Species. "Long-lived species characterized by slow life history and relatively low fecundity are known to be extremely vulnerable to perturbations of a natural or anthropic nature due to their very low replacement rate," said Mahé in the release. "Our results thus suggest it may be even more threatened than expected due to its peculiar life history."

"Consequently, these new pieces of information on coelacanths' biology and life history are essential to the conservation and management of this species," added Mahé. And a microchemical analysis of the creatures' scales might reveal a relationship between its slowed growth and temperature, potentially shedding light on environmental factors in the aging process affecting this and other vulnerable species in a time of accelerating climate change.