Parasitism - Wikipedia
Symbiosis is any type of a close and long-term biological interaction between . In a parasitic relationship, the parasite benefits while the host is harmed. Parasitism takes many forms, from endoparasites that live. In evolutionary biology, parasitism is a relationship between species, where one organism, the parasite, lives on or in another organism, the host, causing it. Some have lifelong relationships with other organisms, called symbiotic Parasitism: One organism (the parasite) gains, while the other (the host) suffers.
A few examples of parasites are tapeworms, fleas, and barnacles. Tapeworms are segmented flatworms that attach themselves to the insides of the intestines of animals such as cows, pigs, and humans. They get food by eating the host's partly digested food, depriving the host of nutrients. Fleas harm their hosts, such as dogs, by biting their skin, sucking their blood, and causing them to itch. The fleas, in turn, get food and a warm home.
Barnacles, which live on the bodies of whales, do not seriously harm their hosts, but they do itch and are annoying. Usually, although parasites harm their hosts, it is in the parasite's best interest not to kill the host, because it relies on the host's body and body functions, such as digestion or blood circulation, to live.
Some parasitic animals attack plants. Aphids are insects that eat the sap from the plants on which they live. Parasitic plants and fungi can attack animals. A fungus causes lumpy jaw, a disease that injures the jaws of cattle and hogs.
parasitism | Definition & Examples | czechbattlefield.info
There are also parasitic plants and fungi that attack other plants and fungi. Parasitism is an extremely successful mode of life; as many as half of all animals have at least one parasitic phase in their life cycles, and it is also frequent in plants and fungi.
Moreover, almost all free-living animal species are hosts to parasites, often of more than one species. Mimicry Mimicry is a form of symbiosis in which a species adopts distinct characteristics of another species to alter its relationship dynamic with the species being mimicked, to its own advantage.
Batesian mimicry is an exploitative three-party interaction where one species, the mimic, has evolved to mimic another, the model, to deceive a third, the dupe. In terms of signalling theorythe mimic and model have evolved to send a signal; the dupe has evolved to receive it from the model.
This is to the advantage of the mimic but to the detriment of both the model, whose protective signals are effectively weakened, and of the dupe, which is deprived of an edible prey. For example, a wasp is a strongly-defended model, which signals with its conspicuous black and yellow coloration that it is an unprofitable prey to predators such as birds which hunt by sight; many hoverflies are Batesian mimics of wasps, and any bird that avoids these hoverflies is a dupe.
Amensalism is an asymmetric interaction where one species is harmed or killed by the other, and one is unaffected by the other.
Competition is where a larger or stronger organism deprives a smaller or weaker one from a resource. Antagonism occurs when one organism is damaged or killed by another through a chemical secretion.
An example of competition is a sapling growing under the shadow of a mature tree. The mature tree can rob the sapling of necessary sunlight and, if the mature tree is very large, it can take up rainwater and deplete soil nutrients.