Which type of ecological interaction benefits one organism while harming another?

The type of ecological interaction that benefits one organism while harming another is known as parasitism. In this relationship, one organism, the parasite, derives benefits such as nutrients or habitat from another organism, the host, which is typically harmed in the process. For example, tapeworms live in the intestines of their hosts, absorbing nutrients from the host's food, which can lead to malnutrition or other health issues for the host. This dynamic highlights the nature of parasitism, where one organism thrives at the expense of another.

Mutualism, on the other hand, is a relationship where both organisms benefit, such as bees and flowering plants. Commensalism involves one organism benefiting while the other is neither helped nor harmed, like barnacles attaching to a whale. Cooperation refers to interactions where two organisms work together for mutual benefit, similar to mutualism but often involves individuals of the same species. Each of these interactions serves a different ecological purpose, making parasitism distinct as it clearly exemplifies a relationship where one party benefits at the other's expense.