What type of interaction is characterized by one species benefiting while the other is neither helped nor harmed?

The interaction described in the question is known as commensalism. In this type of relationship, one species derives benefit from the interaction while the other species remains unaffected, meaning it neither gains benefits nor suffers any disadvantages. An example of commensalism can be seen in birds that nest in trees; the birds benefit by having a place to live, while the tree is not significantly impacted by the presence of the birds.

Understanding commensalism is important in the broader context of ecological interactions, as it highlights the diverse ways species can coexist and impact one another within their environments. This is distinct from mutualism, where both species benefit, parasitism, where one species benefits at the expense of the other, and competition, where both species are negatively affected by their interaction over limited resources.

By recognizing commensalism, one gains insights into the balance of ecosystems and the varying roles species play within them.