The world of sea turtle anatomy is actually quite fascinating. There are only about 100 living marine reptile species in the world that have the capability of surviving in salty ocean water. All turtles species share characteristics in common but any animal that lives in salt water will have many complex differences that will set them a part from the rest.
One of the easiest ways to distinguish between the freshwater turtles and sea turtles is by looking to see whether the turtle has flippers or feet. Sea turtles have flippers whereas freshwater turtles have feet. However, because sea turtles live in the ocean, most people assume they have adapted to breathe underwater. WRONG! They have the ability to hold their breath underwater between 4 and 7 hours when resting. They have a very impressive lung capacity.
Sea turtles could not survive in seawater if it weren’t for special glands located by their eyes called salt glands that release salt in higher concentrations than the surrounding ocean water. Sea turtles cannot have the same salt concentration as the saltwater they are in or else it’s lethal. The salt glands are what produces what most people know as sea turtle “tears”.
Sea turtles have very good vision seeing perfectly clear underwater and blurry above water (opposite of humans). Their weakest sense is their hearing because their ears are very small and are located inside of their head. Sea turtles also have an acute sense of smell that helps them locate their food easily.
All turtles have one characteristic in common: their shell! Shells can vary in size and material. 6 out of 7 species of sea turtles have shells made up of keratin (which is what our fingernails are made out of) allowing their shell to continuously grow with them throughout their life. Leatherback sea turtles are the only species that has a shell primarily made out of cartilage. The Leatherback’s shell is so flexible it allows them to dive over 3,000ft beneath the Earth’s surface!
One of the most unique features about a sea turtle is their BRAIN! As intelligent as these animals are, would you believe their brain is only about the size of a grape! They have a special sense that allows them to detect the magnetic field of the Earth which allows them the navigational ability to migrate as the weather changes. All reptiles rely on the environment to control their body temperature- known as ectothermic. The same magnetic field is what helps female sea turtles navigate thousands of miles year after year to lay their eggs! Pretty Cool!
It’s amazing how sea turtles have adapted to their environment over time. However, it won’t mean anything if we as humans don’t adapt to help them! Keeping our oceans clean and staying “ocean-minded” we can make the world a better place for everyone to live! Flippers Up - Melissa Goldblatt, SAT Board Mbr