In search for the secret of longevity, scientists look closer at animal long-livers. Of special attention are those representatives of fauna whose life span evidently violates the patterns already revealed.
Biologists know well that large animals – elephants, whales, sharks – live longer as a rule than small animals, say, mice or rabbits. This can be explained relatively easily – small creatures have lower body weight and lose heat faster than larger species, their metabolism is more intensive, their hearts beat faster, and their respiration is excessively rapid. Figuratively speaking, their “motor” operates at a higher rate, and the cells of the organism degrade faster than in larger animals.
However, some inhabitants of the animal world, which are not distinguished by large size and should not have lived long, do not follow the pattern. They include the well-known burbot and sturgeon, as well as lobster, two species of tortoise, albatross, Andes condor, and several species of parrots. But the major sensation is a small fish from the family of Percidae. The habitat of this creature, which is called a big-eyed perch, are the ocean depths at the Pacific coast of the USA. Gerontologists are very enthusiastic about this fish because, in spite of all theories, it lives ten times longer than all its “relatives”. The lifetime of common sea perches is about 10-12 years, but the oldest of the big-eyed perch species caught was at least 140. The long-living perch does not lose the ability to multiply – it is even enhanced with age.
Several research centers in the USA try to resolve the enigma of this longevity. Professor Caleb Finch at the University of Southern California, who is considered to be one of the leaders of this trend in gerontology, has been attempting to solve this biochemical riddle for over 10 years now. “Some organisms developed unique anti-aging mechanisms”, he says. Over the lifetime, cells of these creatures experience smaller degradation than cells of man or other animals, which enables them to avoid age-associated diseases. Finch is convinced that in this case we deal with a mechanism which helps to avoid senescence.
Some scientists believe that the cause of this difference in the life span of related species is their habitat. It has been noted that creatures living under conditions that do not contribute to fast metabolism and high consumption of energy live longer.
A sort of a living proof of this hypothesis are three-meter-long tubular worms whose colonies reside at the bottom of the Mexican Bay at a depth of 500 meters. The age of particular species is 170 to 250 years. They are devoid of organs of vision and mouth orifices, and they feed by adsorbing organic substances through their skin. At the same time, close relatives of these long-livers, which also inhabit the bottom of the ocean, but live near geothermal springs, survive for only several years to several tens of years. In the opinion of scientists, life at a big depth without light, almost without food and movement, and, therefore, without stress, is the secret of longevity. Finch, however, is convinced that the environment has no significant effect and cells protect themselves by means of an unknown mechanism.
A group of German scientists working to resolve this enigma has found that lobsters caught in the Atlantic in the region of Boston produce a large amount of the enzyme telomerase. These animals that live over 100 years on average have few features of senescence, comments Boston Globe. The scientists do not rule out that telomerase protects the organism from aging. However, it has been also established that this enzyme occurs in man in 90% of cancer cells and lets them grow uncontrollably.