Turtles

Did you know that turtles are reptiles? Yes, your turtle is a member of the Tuestudines Order. In fact all living turtles are members of the Chelonia crown group. Obviously you know that turtles are animals that are covered by shells made of bone or cartilage and that there is evidence that turtles existed as long as two hundred and fifteen million years ago. This makes turtles older than snakes and lizards! Today there are three hundred living turtle species (some of which are very endangered).

Contrary to popular belief, turtles cannot breathe under water. All turtles (and tortoises) breathe oxygen and, like whales, they must make regular trips to the water's surface to refill their lungs with oxygen. Of course, there is one kind of turtle that is being studied for being able to breathe under water and that is the Australian fresh water turtle. These turtles have large papillae filled cavities that are able to take dissolved oxygen from their papillae—it is sort of like the way that fish make use of their gills.

Like all reptiles, turtles lay eggs and these eggs are leathery and soft. The largest species of turtle lays eggs that are spherical, but the rest of the turtle species are elongated like “regular” eggs. The egg whites of turtle eggs contain protein but it is different than the protein found in birds' eggs and it will not become solid when it is cooked. There are even certain species of turtle whose young depend on the temperature to determine their gender. If the nest is in a warmer climate, the eggs will produce female turtles. If the nests are in a colder client, the eggs will produce male turtles. The nests are typically made of a sand or mud hole that is covered up. Unlike other animals, turtles do not incubate their young by sitting on them. The eggs are left alone. Then when the eggs hatch, the baby turtles dig up to the surface and then go to the water on their own. Turtles do not care for their young.

Here is an interesting turtle fact: With most animals, their internal organs break down over time and become increasingly less efficient as they age. With a turtle, this is not the case. A turtle that is one hundred years old has kidneys, lungs and a liver that are almost exactly the same as a turtle that is very young. When researchers discovered this, they began examining the genome of the turtle to see if there is such a thing as a “longevity gene.”

The word turtle has also been used to describe sea turtles, tortoises and terrapins, and the smaller terrestrial and freshwater turtles are often kept as house pets. The most common types of turtle pets are the Russian Tortoises, the Greek spur-thighed tortoises and the red ear sliders, which are actually terrapins.

Many people have found the turtle fascinating and over the years, turtles have been one of the most popular animals to study.