Commensalism: Definition, Examples, and Significance

commensalism

one organism benefits and the other is unaffected

Commensalism is a symbiotic relationship between two organisms in which one organism benefits, while the other is neither helped nor harmed. In commensalism, one organism, called the commensal, obtains benefits from the other organism, called the host, without causing any harm to the host. The commensal may use the host as a source of food, shelter, or transportation, but does not cause any damage or harm to the host.

For example, a commensal relationship can be seen in the case of barnacles and whales. Barnacles are marine animals that attach themselves to the skin of whales to obtain a stable surface to live on. In this relationship, the barnacles benefit by getting a stable surface for attachment and a steady flow of food particles, while the whales are not affected either positively or negatively.

Another example of commensalism exists between cattle egrets and grazing cattle. The cattle egret feeds on insects that are disturbed by the movements of the cattle while grazing, and so obtains an easy source of food, whilst the cattle are not harmed.

In conclusion, commensalism is a type of symbiotic relationship in which one organism benefits, while the other is not affected. The relationship falls under the category of symbiosis because the two organisms live together, but the word ‘commensal’ refers to the organism that obtains benefits without causing harm or providing any essential services to the host organism.

More Answers: