thus giving it the name "brindled gnu". The manes of both sexes appear long, stiff, thick, and jet black, the same colour as the tail and face. While the manes of the western and eastern white-bearded wildebeest are lank, those of the Nyassaland wildebeest and common wildebeest stick up. Scent glands, which secrete a clear oil, are present in the forefeet and are larger in males than females. In terms of skull length, the smallest subspecies of the blue wildebeest is the western white-bearded wildebeest. It is also the darkest subspecies; the eastern white-bearded wildebeest is the lightest race. Both subspecies possess a creamy white beard, whereas the beard is black in both the Nyassaland wildebeest and the common wildebeest. The longest muzzles are found in the Nyassaland wildebeest, and the shortest in female western white-bearded wildebeest. Horns Both sexes possess a pair of large horns, which are shaped like parentheses. These extend outward to the side, and then curve upward and inward. In the males, the horns can be long, while the horns of the females are long. Despite being an antelope, the blue wildebeest possesses various bovine characteristics. For instance, the horns resemble those of the female African buffalo. Further, the heavy build and disproportionately large forequarters give it a bovine appearance. Ecology and behavior The blue wildebeest is mostly active during the morning and the late afternoon, with the hottest hours of the day being spent in rest. These extremely agile and wary animals can run at speeds up to , waving their tails and tossing their heads. An analysis of the activity of blue wildebeest at the Serengeti National Park showed that the animals devoted over half of their total time to rest, 33% to grazing, 12% to moving about (mostly walking), and a little to social interactions. However, variations existed among different age and sex groups. The wildebeest usually rest close to others of their kind and move about in loose aggregations. Males form bachelor herds, and these can be distinguished from juvenile groups by the lower amount of activity and the spacing between the animals. Around 90% of the male calves join the bachelor herds before the next mating season. Bulls become territorial at the age of four or five years, and become very noisy (most notably in the western white-bearded wildebeest) and active. The bulls tolerate being close to each other and of