Zebra stallions are the protectors of the herd, watching over a harem of five to six females, usually. These family groups join with others to create a herd, but each stallion stands watch over his ladies and children to protect them from danger and other stallions who might get the idea to steal a few of them. They often fight each other for rights to certain females, so the biggest and strongest usually win. This leads to the males being larger than the females, averaging 700 pounds but topping out at 990 pounds.