What is the relationship where one species benefits and the other is harmed?

The relationship where one species benefits while the other is harmed is known as parasitism. In parasitism, the parasite relies on the host for survival, often at the expense of the host's health or well-being. For example, tapeworms living in the intestines of host animals absorb nutrients from the host, which can lead to malnutrition, disease, or even death of the host organism. This interaction highlights how one organism can thrive at the cost of another, emphasizing the detrimental impact on the host while providing a clear advantage to the parasite.

In contrast, other types of relationships, such as mutualism, involve mutual benefits for both species, while commensalism sees one species benefit without affecting the other. Predation involves one species preying on another, leading to the death of the prey, but its focus is on the act of hunting rather than a parasitic relationship. Understanding these various interactions is crucial for grasping ecological dynamics.