WHY DO TURTLES & TORTOISES LIVE SO LONG?

Turtles  and tortoises are some of the most long-lived

 members of the reptile family. Even small species that

   are typically kept as pets, like box turtles and

 terrapins, live between 30 and 40 years if they're kept

 healthy. Larger species such as sea turtles are 

estimated to live about 80 years. The giant tortoise, the

 largest of all land turtles, typically lives at least a

 century. Some have even been known to live for more

 than 200 years! 

Theories

There is no hard and fast answer for why turtles and tortoises live so long. There are, however,

 a few theories, including the slow rate of their metabolisms, naturally healthy lifestyles and 

evolutionary theories regarding reproduction. Of course, the longevity of a turtle's life depends

 on surviving predators, pollution and other environmental risks. New hatchlings are especially

 vulnerable to predators until their shells harden. As for domestic turtles, whether they live out 

the full extent of their natural lifespan depends largely on the type of care they receive.

Slow Growth

One reason turtles are believed to have such long lifespans is their slowness. Turtles continue 

to grow very slowly  throughout their lives. This prevents them from aging in the same way birds

 and mammals do. Thanks to their slow metabolisms, they can survive long periods without

 food or water, which also gives them a greater chance of survival in harsh conditions.

Reproduction

Another explanation is that the long lives of turtles and tortoises gives them an evolutionary 

advantage that aids in effective reproduction. Wild turtles tend to live in harsh environments that

 aren't always conducive to breeding. Their long lifespans provide them with more opportunities 

to procreate. Turtles also have natural protection from predators in their tough shells and thick, 

armored skin, which, unlike animals that tend to be prey, gives them the luxury of being able to 

take their time reproducing.

Lifestyle

The longest-lived of all the turtle species, the Galapagos giant tortoise, eats a strict vegetarian

 diet that's full of greens and free of fat and cholesterol. These slow-moving gentle giants are 

extremely docile and peace-loving creatures that generally live stress-free lives. This 

combination of calm and healthy living is likely another explanation for their extreme longevity.