:In ecology, we notice that populations of animals and plants tend to change; that is an observation. The [[theory]] is that a type of organism will tend to increase its population wherever it finds a suitable environment, limited only by such factors as food and predators. | :In ecology, we notice that populations of animals and plants tend to change; that is an observation. The [[theory]] is that a type of organism will tend to increase its population wherever it finds a suitable environment, limited only by such factors as food and predators. |