Vertebratic animals include

• fish,
• amphibians,
• reptiles,
• birds and
• mammals.

Vertebratic animals have an internal supporting structure known as a skeleton. The skeleton consists of a backbone made of vertebrae, which is connected to the limbs. The skeletal system of a vertebratic animal helps to protect and support the animal's body. 

Mammals are animals that give birth to living offspring. These offspring are fed milk from the mother's mammary glands. This separates mammals from other kinds of animals, which do not have mammary glands and do not give birth to living, developed offspring. 

Like birds, mammals are warm-blooded animals. This means that they maintain a steady body temperature, even when the air temperature outside is extremely cold or hot. 

Many mammals have a protective fur layer and a fat layer. These features help the mammal to maintain their body temperature in cold environments. Humans do not have fur, which is why we need to wear clothes to stay warm. 

Mammals have powerful circulatory systems. This makes it possible for mammals to move at great speeds and maintain their body temperature. 


Mammals are warm-blooded animals, which means that their body temperature is steady. A gorilla also has a thick fur.