Zebra Grazing (IMAGE) University of Utah Caption A zebra grazes on grass at Kenya's Lake Nakuru National Park. Zebras are among the African animals that grazed during the past 4 million years and still do today. Most major African herbivore groups tried grasses, but many switched to browsing on trees and shrubs or went extinct. Credit Mahala Kephart Usage Restrictions Credit required. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.