Mammals are defined by having a number of shared characteristics:

Vertebrates

All mammals have a back bone or spinal chord made up of a number of individual vertebrae.

 

Warm-Blooded

Mammals are warm-blooded creatures, they have a fairly high body temperature which is maintained by the body’s metabolism.

 

Tetrapods

All mammals have four limbs. Some mammals walk on all four limbs, others walk on two and others can do both.

 

Hair

Mammals have hair which grows from follicles found in the skin. Functions of the hair include warmth, protection and to act as a sensor.

 

Respiration

Mammals breathe using a pair of lungs composed of spongy like material. The breathing rate of mammals varies – a whale might only breathe once every two hours while smaller rodents breathe 150+ times a minute.

 

Reproduction

Most mammals give birth to live young but a few lay eggs.

 

Mammals Pages

Features
Classification
Mammals A – Z