Are Turtles Mammals?

Mammals are animals that have hair or fur. However, dolphins are mammals and they only have hair for a short time after birth. Mammals have vertebrae and are warm-blooded, though there are some mammals, such as the rock hyrax and the sloth, that aren’t as warm-blooded as mammals usually are. Mammals breathe air, too. Yet, cetaceans such as dolphins and whales, and sirenians such as manatees, live their entire lives in water.

Mammals also give birth to live young and nurse their babies with milk from their mammary glands, however, the platypus and the echidna lay eggs. Most mammals are placental. The placenta is a structure that delivers nutrients to the developing baby in the uterus. However, some mammals are marsupials, and their babies are born underdeveloped and continue their development in their mother’s pouch. So, are turtles mammals? Keep reading to find out.

Why Some Might Think Turtles Are Mammals

People might think turtles are mammals because turtles breathe air. Additionally, turtles have vertebrae. One might even think that turtles are mammals because their meat is sometimes used for food, similar to the meat of mammals such as cows and pigs. Turtles also have lower jaws, which is another hallmark of a mammal. They don’t have hair, but the scales of their shells are made of keratin, which is what human hair is made of.

Despite some similarities, a turtle is not a mammal. Turtles are reptiles that belong to an order called Testudines. This means that turtles have a shell that is part of their skeleton. The shell was formed when their ribs and vertebrae flattened and fused with their skin, developing the bony plates that surround their bodies.

How Are Turtles Like Reptiles?

Most reptiles are cold-blooded, or ectothermic, which means their body temperature is determined by their environment. Turtles are also ectothermic. Their shells help with thermoregulation, as they can retain heat to help the turtle stay warm. Reptiles do not have hair or fur, they have scales or scutes, which are what make up the outer layer of the turtle’s shell. Reptiles are tetrapods, meaning they are vertebrates with four limbs, or they have an ancestor with four limbs. Turtles also have four limbs. However, different species may have limbs that are specially adapted for digging, walking, or swimming, depending on their habitat.

Reptiles breathe air through their lungs. Although there are some turtles that spend much of their lives in the water, all turtles must also breathe air. Reptiles lay eggs, just as turtles do, and they lay those eggs on land. The developing young also need to breathe oxygen, which passes through the egg shells. Reptiles also undergo internal fertilization. Turtles’ eggs are fertilized inside their bodies, too. Most reptiles do not care for their offspring post-hatching. Other than covering up the eggs after they’ve been laid, a turtle provides no parental care. So, while turtles may not fit in with the mammal class, they fit in perfectly with the reptiles.