# 12.5: Assumption of the basic model

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This basic model of interacting predators and prey reveals the tension between population growth and decline, and shows the kind of cycling that characterizes predator–prey systems. It has, however, a number of simplifying assumptions that can be relaxed in more detailed studies, including the following:

1. The predator lives only on this prey, and perishes without it.
2. The prey has no carrying capacity of its own—only that imposed by the predator.
3. The environment is homogeneous and prey have no hiding places.
4. Growth is continuous, with no age structure, maturation periods, and so forth.
5. The number of prey taken is proportional to the number of prey present. In other words, predators are never satiated.
6. Genetics are uniform within each species, and there is no evolution.

Relaxing all of these assumptions is a book in itself, but we will relax some of them in sections ahead.

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