Interactions Between Species

General interactions between species

Mutualism

An interaction where both species benefit.

Commensalism

(+/0) An interaction where one species benefits and the other is neither helped nor harmed, like barnacles hitching a ride on a whale.

Parasitism

(+/-) An interaction where one organism (the parasite) lives on or inside another (the host) and harms it, such as a tick drinking blood from a deer.

Predation

(+/-) An interaction where one species (the predator) kills and eats another (the prey), like a lynx hunting a hare.

Herbivory

(+/-) An interaction where an organism eats parts of a plant or alga, such as a caterpillar feeding on a leaf.

Competition

(+/-) An interaction where individuals of different species compete for the same limited resource, such as two species of birds fighting over the same nesting site.

Amensalism

(+/0) An interaction where one species is harmed or destroyed while the other remains unaffected, like a heavy animal stepping on and killing grass.