Not all adaptations involve physical structures. Zebra have several behavioral adaptations in addition to their physical adaptations. For example, most species of zebra live in herds, like other members of the horse family. Unlike most other horse species, zebra often herd with other animals as well, such as giraffes. While this behavioral adaptation offers many of the same advantages for all herding animals -- such as more eyes to spot predators -- living in groups enhances some other zebra adaptions. In groups, the stripes help break up their outlines, making it harder for predators to pick out the shape of individual zebra. This benefits all members of the group. Even the Grevy's zebra, which does not live in true herds, still tend to form small groups that can offer some of the same advantages.