Their age can not be determined. They can be killed by predators, fishermen, illnesses. Sea urchins live in their 100 years of age, as in 10. Previously, scientists believed that they live for 10-15 years. It turned out that even survivors of the atomic bomb tests live, as if nothing had happened. Elder sea urchins grow at a constant rate, not noticing changes in the environment.
They are constantly growing. All life. The largest of the caught ones reached 19 centimeters. These lived about 200 years. It is already known that a centennial sea urchin can give offspring as young. Even better, because in adult urchins eggs and spermatozoa of better quality than young ones.
Japan is the main consumer of sea urchins. It consumes 500 tons of sea urchin annually. Maybe this explains why the life expectancy in Japan is 85 years, and this is despite the fact that the country has survived a nuclear bombing.
The sea urchin is immortal. Its caviar has in its composition a very wide range of active substances. They can stimulate the body to work in normal mode, regardless of unfavorable environmental factors.