Pᴀʀᴀsɪᴛɪsᴍ
ᴛʜᴇ sᴄʀᴀᴍʙʟᴇᴅ ʟᴇᴛᴛᴇʀ ɪs Pᴀʀᴀsɪᴛɪsᴍ
Mᴇᴀɴɪɴɢ
- Parasitism is a symbiotic relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans.There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophically transmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. Classic examples include interactions between vertebrate hosts and tapeworms, flukes, the malaria-causing Plasmodium species, and fleas.Parasites reduce host fitness by general or specialised pathology, from parasitic castration to modification of host behaviour. Although parasitism is often unambiguous, it is part of a spectrum of interactions between species, grading via parasitoidism into predation, through evolution into mutualism, and in some fungi, shading into being saprophytic.
