Ecological Interactions

What are some ecological interactions? Population – group of individuals of the same species living in the same area, potentially interacting Community – group of populations of different species living in the same area, potentially interacting What are some ecological interactions?

Why are ecological interactions important? Interactions can affect distribution & abundance. Interactions can influence evolution. Think about how the following interactions can affect distribution, abundance, and evolution.

Types of Ecological Interactions competition predation parasitism mutualism commensalism symbiosis

Competition – two species share a requirement for a limited resource  reduces fitness of one or both species

Predation – one species feeds on another  enhances fitness of predator but reduces fitness of prey herbivory is a form of predation

Parasitism – one species feeds on another  enhances fitness of parasite but reduces fitness of host

Mutualism – two species provide resources or services to each other  enhances fitness of both species

Commensalism – one species receives a benefit from another species  enhances fitness of one species; no effect on fitness of the other species

Symbiosis – two species live together  can include parasitism, mutualism, and commensalism

Organizing Ecological Interactions effect on species 1 + 0 - predation herbivory parasitism + - commensalism mutualism effect on species 2 competition