on leaf blades of short grasses and nibbling off leaf sheaths from grass stems. In addition to this, it can derive nutritious food even from tall senile grasses. These adaptations of the hartebeest enable the animal to feed well even in the dry season, which is usually a difficult period for grazers. For instance, in comparison with the roan antelope, the hartebeest is better at procuring and chewing the scarce regrowth of perennial grasses at times when forage is least available. These unique abilities could have allowed the hartebeest to prevail over other animals millions of years ago, leading to its successful radiation across Africa. Grasses generally comprise at least 80 percent of the hartebeest's diet, but they account for over 95 percent of their food in the wet season, October to May. Jasminum kerstingii is part of the hartebeest's diet at the start of the rainy season. Between seasons, they mainly feed on the culms of grasses. A study found that the hartebeest is able to digest a higher proportion of food than the topi and the wildebeest. In areas with scarce water, it can survive on melons, roots, and tubers. In a study of grass selectivity among the wildebeest, zebra, and the Coke's hartebeest, the hartebeest showed the highest selectivity. All animals preferred Themeda triandra over Pennisetum mezianum and Digitaria macroblephara. More grass species were eaten in the dry season than in the wet season. Reproduction Mating in hartebeest takes place throughout the year, with one or two peaks that can be influenced by the availability of food. Both males and females reach sexual maturity at one to two years of age. Reproduction varies by the subspecies and local factors. Mating takes place in the territories defended by a single male, mostly in open areas. The males may fight fiercely for dominance, following which the dominant male smells the female's genitalia, and follows her if she is in oestrus. Sometimes a female in oestrus holds out her tail slightly to signal her receptivity, and the male tries to block the female's way. She may eventually stand still and allow the male to mount her. Copulation is brief and is often repeated, sometimes twice or more in a minute. Any intruder at this time is chased away. In large herds, females often mate with several males. Gestation is eight to nine months long, after which a single calf weighing