What Makes a MammalA warm-blooded animal with a backbone that breathes air, and has at least some hair at some point during its life. The females have glands that produce milk, which they feed to their young.?
There are more than 4,000 different speciesA group of individuals that have many of the same characteristics, and are different from all other animals in some important way. Hamsters and mice are two different species of rodent. of mammals. The smallest is the hog-nosed bat, which weighs 0.05 ounces. The largest is the blue whale, which can be 100 feet long and weigh 150 tons. But whether they live on land or water, all mammals share some common characteristics.
- Are vertebrates (which means they have a backboneThe column of bones (spine) in the back of many animals. It supports the body. An animal with a backbone is called a vertebrate. or spineA stiff, sharp projection on an animal; another word for quill.).
- Are endothermic. Also known as “warm-bloodedAn animal whose body temperature stays fairly constant, no matter what the temperature of the air around it.,” endothermic animals regulate their own body temperate which allows them to live in almost every climate on Earth.
- Have hair on their bodies.
- Produce milk to feed their babies. This allows them to spend more time with their young and teach them important skills they need to survive on their own.