Scientists have discovered a new record holder for longevity in the animal world. Strangely, this is not a turtles but polar sharks can live over 400 years!
Polar Sharks, also called Greenlandic fishery (Somniosus microcephalus), live in the North Atlantic, both at the surface and at a depth of about 2 km. Adults reach a length of 4-5 m, their anatomy is poorly understood, although biologists know that these are some of the slowest known sharks. Such a mode of life usually goes hand in hand with longevity, but no one knew that sharks, polar can live so long!
The pioneer research sharks Polar is Dr. Julius Nielsen of the University of Copenhagen. The age of the species in the traditional way is determined through analysis of calcified tissues.
Such in the sharks do not exist. Nielsen team came up with a different way and therefore collected the eye lenses 28 female animals that become entangled in fishing nets. Biologists have studied the center of the lens, ruling during embryonic development and identified, how old is the shark.
The results were surprising. It turned out that the average life expectancy of the sharks was 272 years, while the two biggest female (5 m) survived the 335 respectively and 392 years. Interestingly, sharks, polar reach sexual maturity at the age of only sexually 156 +/- 22 years of age.
Recent studies have confirmed that the sharks are the longest living vertebrate species known on Earth.
Analysis of the crystalline lens
To work around this problem, the researchers used a technique of carbon dating 14 on the eye of the sharks. This radioactive molecule binds in the body of the shark during prenatal development. Well to shelter inside the lens capsule, the stock of carbon 14 evolves more thereafter, unlike what happens in other parts of the body. The amount of carbon 14 in the lens therefore reflects that of the atmosphere during its manufacture.