african bark black coats black skin Bray common zebra equids fast grant’s zebra grazers herbivores herbivorous herd herds individual mammal patterns plains zebra social stripes ungulates unique white fur white stripes zebra black-&-white black-coats black-skin common-zebra grant’s-zebra greyscale monochrome plains-zebra striped white-fur white-stripes erect manes harems mohawk-like manes stiff manes Africa animal creature exotic free natural nature plains safari savannah untamed wild erect-manes mohawk-like-manes stiff-manes gray grey patterned blue city crossing man pedestrian plain road roads roadsign roadsigns sign signs street townurban traffic walk warning