Why can't eyebrows be as long as hair?

Hair pores

Although I just went to cut my hair, but just over a month later, my hair grew longer and needed to be trimmed again. For eyebrows, there has never been a short cut but it always seemed like that.

According to research by scientists, the length of human hair is caused by capillaries (capillary bags) that grow out hair that is large or small in deciding.

The eyebrows can only be up to one year old and a certain length, then over time will fall away, where the fall away will grow new hairs. In different positions on the body, hair growth hairs of different lengths by hair in different positions will have different capillary bags. At the same time, each type of capillary can only support a certain length of hair. The cilia of the eyebrow has much less tolerance than the cilia of the hair. Therefore, when the eyebrows reach a certain length, the capillary cannot stand it, the eyebrows will stop growing, self-falling cannot grow as long as hair.