Conceptual Overview of Evolution of Parasitism

As the name suggests, parasitism is a close relationship between species in which one organism, the parasite, lives inside another organism, the host, causing harm to the latter, and the host is structurally tailored to the parasite. Essentially, parasitism describes the relationship between two species where one organism lives on or inside another and benefits from it by harming the other. Furthermore, parasites affect host behavior, fitness, and population size, often affecting trophic interactions, food chains, competition, biodiversity, and keystone species. It is evident from these interactions that parasites shape communities and ecosystems. In addition, parasites can greatly influence host behavior and fitness, regulate host populations, influence trophic interactions, food webs, competition, biodiversity, and keystone species. Community- and ecosystem structures are shaped by parasite interactions.