Competition within and between species is an important topic in biology, specifically, in the field of ecology. Competition between members of a species is known as intraspecific competition. Competition is also present between species is known as interspecific competition. First, a limited amount of resources, such as food, water, territory, are available, and several species may depend on these resources. Thus, species, and often individuals within a species, compete to gain these resources. As a result, several species less suited to compete for the resources may either adapt or die out. According to evolutionary theory, this competition within and between species for resources plays a critical role in natural selection.

Types of competition

Interference competition - occurs directly between individuals via aggression etc. when the individuals interfere with foraging, survival, reproduction of others, or by directly preventing their phyisical establishment in a portion of the habitat.

Exploitation competition - ocurrs indirectly through a common, limiting resource, which acts as an intermediate. For example the use of the resource(s) depletes the amount available to others, or they compete for space.

Apparent competition - ocurrs indirectly between two species which are both predated upon by the same predator.

Competition | Ecology