All modern breeds of cattle are descended from the now-extinct aurochs, wild cattle of Europe and the Near East who had been domesticated by 6500 b.c. As herd animals, cows have a cooperative nature. The movement and assembly of the group are accomplished through various means of communication, with a greater reliance on cooperation than on domination. Although a hierarchy is established within each herd, dominant cows usually are not herd leaders. Instead, the leader at any particular time can be any one of a pool of animals.
Cows have a nine-month pregnancy.
A cow will separate herself from the herd shortly before her baby is born. After birth, she begins licking the newborn. They are caring mothers and will bravely protect their young. Dairy cows form strong bonds, especially among mothers and young and among peers. If they are allowed to stay together, the bond between a cow and her calf remains even after weaning.