Keystone species mussel population explodes uncontrollably, driving out most other species. These creatures need not be apex predators. Sea stars are prey for sharks, rays, and sea anemones. Sea otters are prey for orca. The jaguar, whose numbers in Central and South America have been classified as near threatened, acts as a keystone predator by its widely varied diet, helping to balance the mammalian jungle ecosystem with its consumption of 87 different species of prey. The lion is another keystone species. Keystone mutualists are organisms that participate in mutually beneficial interaction and the loss of which would have a profound impact upon
Barbary sheep Barbary sheep The Barbary sheep ("Ammotragus lervia") is a species of caprid (goat-antelope) native to rocky mountains in North Africa. Six subspecies have been described. Although it is rare in its native North Africa, it has been introduced to North America, southern Europe, and elsewhere. It is also known as aoudad, waddan, arui, and arruis. Barbary sheep stand tall at the shoulder and weigh . They are sandy-brown, darkening with age, with a slightly lighter underbelly and a darker line along the back. Upper parts and the outer parts of the legs are a uniform reddish brown or grayish brown.