The tortoise is one of the few animals that have both an exoskeleton and an endoskeleton. There are also tortoises alive today that were around in the days of sailing ships and colonization of the globe. The oldest known tortoise alive today has a name, Jonathon and Jonathon lives on the island of St Helena.
He was hatched in the year 1832 and is a Seychelles giant tortoise, this was the year that Charles Darwin arrived in South America for the first time on the sailing ship Beagle.
In his lifetime, Jonathan has lived through two world wars, numerous smaller wars,the Russian Revolution, seven monarchs on the British throne and 39 US presidents and as at 2019 was still going strong at the ripe old age of 187 years. This matches the age of the tortoise given by Captain James Cook to the Tonga Royal family in 1777 and which died in 1965.
Tortoises are solitary creatures but in a group are referred to as a creep of tortoises. When threatened they retract their heads and limbs and wait for the danger to pass or give up trying to get through the shell.
Some eagles pick up a tortoise and fly with it until it finds some rocks below and drops it to break it open. Some alligators can break through a tortoise shell as can a jaguar. But the tortoise shell is pretty good protection against most threats.
The claws are really good for digging which comes into its own when the tortoise is preparing for winter or even when its digging burrows which it uses to regulate its temperature. Another important digging time is for the laying of eggs.
Most tortoises are herbivores but some species will eat insects worms and carrion when available.
When it comes to reproduction, the female can store sperm and use it to fertilize eggs for up to four years. Each successive year sees a reduction in fertility though. During the courtship and mating process there are often fights between contesting males which try to flip each other onto their backs.
Although some species can right themselves fairly easily others cant, its really dependent on the shell shape. If a tortoise finds itself on its back for a long time it does stand to die.
Tortoises lay up to 30 eggs at a time depending on the species. These eggs are laid in sandy soil that gets a lot of sunlight to complete the incubation process. Some tortoises will lay their eggs in the apron in front of their burrows although its not necessary to be so close as the mother doesn’t have any further interaction once the eggs are laid and covered with sand. This process of digging the hole, laying the eggs and covering them can take up to 4 hours to complete.
The top part of the tortoise shell is called a carapace and the scales are called scutes, all made from keratin (same as our fingernails).