animal black Chordata dolichohippus equidae equus equus grevyi equus quagga equus zebra hippotigris mammal mammalia perissodactyla savage texture white widlife wild zebra adult backside Chapman's Zebra Equus quagga chapmani graze herbivore horse leg nature rear stripe stripes tail foal hoof mane young african bark barking black-&-white black-coats black-skin Bray braying Camouflage common-zebra contrast contrasting equids equus-quagga-boehmi erect-manes family-groups fast grant’s-zebra grazers harems herbivores herbivorous herd herds individual mammals mohawk-like-manes patterns plains-zebra social stiff-manes subspecies ungulates unique unique-stripe-patterns white-fur white-stripes