Association of Populations

Nature of the Interaction

Competition is an interaction between individuals or populations that is mutually detrimental. Due to limited supply of resources (food, water, territory) such interaction could result in both species suffering losses.

In certain situations, competition between 2 distinct species results in the stronger species overpowering the weaker or the weaker species outnumbering the stronger.

describes the relationship between two species which do interact but do not affect each other. It is to describe interactions where the fitness of one species has absolutely no effect whatsoever on that of other. Neutralism is difficult to prove as at least one species displays a minor benefit.

It describes the relationship between individuals of different species where both species derive a common benefit. If the mutual relationship between species is strong enough, it is generally considered by scientists to be symbiosis. This relationship dictates that one organism cannot live without the other.

Is a method in which two species interact with each other beneficially however the have no obligatory need to interact with each other but instead interact purely for the extra gain. It is not necessary for protocooperation to occur since growth and survival is possible outside of this. The interaction usually occurs between to distinct species.

Is the interactions between 2 species where one species benefits at the expense of another. Predation is an interaction between organisms in which one organism captures the complete biomass of the other organism. It is generally synonymous with carnivorous animals, however it also applies to herbivores as well.

A parasitic relationship is one in which one member of the association benefits while the other is harmed. Parasitic symbioses take many forms, from endoparasites that live within the host's body to ectoparasites that live on its surface. In addition, parasites may be necrotrophic, which is to say they kill their host, or biotrophic, meaning they rely on their host's surviving. Biotrophic parasitism is an extremely successful mode of life.

Commensalism is a relationship between two species where one species derives a benefit from the relationship and the second species is unaffected by it.

Commensalism is much more difficult to demonstrate than mutualism. For true commensalism, the second species must be unaffected by the presence of the first, but commonly a detailed study of the relationship will show some affect on the second species.

Is an interaction between two species of organisms where one impeding the success of the other without being affected positively or negatively by the existence of the other organism.

Examples of Population Interaction

Example of sea anemone competing for space in a tidal pool at the intertidal zone.

Lion and Hyena compete for the same food in the Serengeti plains of South Africa.

Desert tarantula that lives amongst the cactus plants. Neither one if effected however the tarantula might get some shade from the cactus.

A common example is the relationship between flowers and butterflies.

Another common example is the relationship between clown fish and sea anemone.

Ants and Aphids may sometimes cooperate so easy is mutually benefited in someways or the other. However each organism is fully capable of survival without the other.

The female mosquito ingests blood from its victim without harming it. The male ingests plant juice.

The clown fish derives its protection from the sea anemone while the sea anemone appears to be unaffected by the fish's presence.

The Remora fish clings to the shark body with special suctions fins while feeding off the scraps of food that escapes the jaws of the shark.

A classic example is the Penicillin secretion which is actually a fungal secretion. This secretion has detrimental effects on bacteria.