Last Reviewed and Updated on August 6, 2022
Not all birds fly, and not all mammals walk on land or give birth to live young… In nature, the lines are often blurred. Bats can fly, but they don’t have feathers, so you might be wondering, are bats birds or mammals? Let’s take a closer look at these night flyers and explore under which category they fall.
What defines a bird, and what defines a mammal?
When you think about birds, you think about feathers, eggs, and flying. And when you think about mammals, you usually think about animals giving live birth, fur, and walking on land or swimming. But what about an ostrich or a penguin who can’t fly or a platypus, a mammal that lays eggs?
Let’s look at what defines a mammal. A mammal is any class of warm-blooded, higher vertebrates (has a backbone or spinal column) that feed their young with milk from mammary glands. The skin of a mammal is usually covered with hair (but the hair can be rare, like with humans). In addition to that, three middle ear bones are also required as well as the neocortex (part of a brain).
Birds, on the other hand, are characterized by feathers, toothless beaked jaws, laying of eggs, high metabolic rate, four-chambered heart, and lightweight skeleton.
Are bats birds or mammals?
If you read what defines a bird and what defines a mammal, you most likely already guessed that bats are mammals.
If you haven’t had a chance to take a closer look at a bat, things might not be super clear, so let’s go over the criteria.
Bats are covered with fur and not feathers. They also don’t have beaks.
They don’t lay eggs; they give birth to live young and feed their young with their milk. These animals are warm-blooded and have four-chambered hearts and a backbone. As is the case with all other mammals, they also have three middle ear bones and a neocortex.
They are unique when it comes to mammals, though, as no other species of mammals is capable of true flying.
Be sure to also read: facts about bats.