2024-08-01 06:00:08
Beneath the cold waters of the Arctic and North Atlantic, the Greenland shark has an astonishing characteristic: its longevity.
While this predator can live for more than 500 years, scientists have recently unraveled the mystery of its exceptional longevity. Contrary to previous hypotheses, the key lies in a metabolism that remains constant over the temps.
Greenland sharks (Dreamy microcephalus), which can reach depths of 2,647 meters, live in average 250 years, and some even exceed 500 years. Scientists thought that this longevity was due to their environment extremely cold and their weak activity. However, new research presented at the Society of Experimental Biology Conference in Prague reveal a surprising factor: their invariable metabolism.
A team of researchers took muscle tissue samples from 23 Greenland sharks caught off Disko Island in central Greenland. They measured the activity of five different enzymes to assess the sharks’ metabolic rate and response to environmental temperatures. They then estimated the sharks’ ages based on their body length, finding individuals ranging from 60 to 200 years old.
The results revealed that the sharks’ enzyme activity did not vary with age, unlike most animals where enzyme efficiency declines over time. This metabolic stability appears to prevent cellular degradation, thus explaining the exceptional longevity of Greenland sharks.
Tissue collection from a Greenland shark captured on the south coast of Disko Island, central Greenland.
Credit: Ewan Camplisson
The tests also showed that enzyme activity increased significantly at higher temperatures. This suggests that if Greenland sharks were exposed to warmer conditions, their metabolism could increase significantly, potentially changing their lifestyle. These tests are particularly relevant given the predictions of rising ocean temperatures due to global warming.
These findings pave the way for further research into shark aging markers and metabolism, with the aim of better understanding how to protect them in a rapidly changing environment.
1722497648
#Scientists #discover #secret