In which type of symbiotic relationship does one organism benefit while the other is not significantly affected?

In commensalism, one organism derives benefits while the other organism is neither helped nor harmed significantly. This type of relationship illustrates how some species can coexist in a shared environment, where one species might utilize resources provided by another without causing any negative effects.

For example, birds that build nests in trees can be considered in a commensal relationship with the trees. The birds gain a safe place to live and raise their young, while the tree remains unaffected by the presence of the birds.

Understanding commensalism contrasts with mutualism, where both organisms benefit, and parasitism, where one organism benefits at the expense of another, causing harm. Competition involves two or more organisms competing for the same resources, which creates a very different dynamic than what is observed in commensal relationships.