The Predation reference article from the English Wikipedia on 24-Apr-2004
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Predation

Predation is an interaction between organisms (animals) in which one organism captures and feeds upon another called the prey. The predator is usually the larger and stronger of the two. Predators are always either carnivores or omnivores. The prey might typically be a herbivore, but some predators feed on anything they can capture, including other predators.
Predation by a centipede on a large spider
This centipede crawled up under the eave of a shed to capture
and feed upon a predatory cane spider hunting there (enlarge)

Humans naturally think of large cats (lions, tigers) and large reptiles (crocodiles) as typical predators, or perhaps even snakes, many of which are predatory on small mammals. However, spiders, centipedes, most lizards and turtles, and frogs are also voracious predators.

The Volterra-Lotka equations describe a simple mathematical model of the interaction between predators and prey.