Why do some people become midgets?

This is due to a disorder in the endocrine glands. Some dwarfs have short arms and legs but a normal sized head and trunk. This is due to diseases of the cartilage. A lack of hormones in the pituitary gland also causes dwarfism. Other glands like the adrenal gland, thyroid, male and female sex glands can also play a role in deciding the height of a person. However, for a pygmy, his height is normal as heredity determines it.