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
Predator (fictional species) tactical nuclear bomb on the town, incinerating both combatants as well as the few remaining humans in the city. The salvaged plasma pistol is then taken by United States Military officers to Ms. Yutani. In "Predators", it is revealed that there are two warring Predator tribes: one group uses quadrupedal hunting beasts and elaborate traps to hunt, and the other hunts traditionally. An international group of soldiers and dangerous criminals from different locations from Earth are dropped onto a forested planet used as a Predator game reserve. After numerous skirmishes resulting in the deaths of two Predators and all but