What is parasitism? Differences and similarity of parasitism with predation

The article describes what parasitism is, what its forms are. In addition, the question of the similarity and difference of this phenomenon with predation is considered.

A life

Life on our planet exists about 4 billion years. And during this time, a huge number of biological species had appeared on it, developed, and disappeared. And, probably, this process will continue. Despite this, any form of life, even the simplest and smallest, is very astonishing from a scientific point of view. However, like some forms of species existence. One of them is parasitism. This phenomenon is quite common. So what is parasitism, what forms does it have, what are its features? In this we will look further.

Definition

Parasitism is one of the main types of coexistence of organisms. Unlike the others, it is characteristic for him that two or more living beings that do not have a genetic connection with each other and, in general, are heterogeneous, live together for a long time, but remain antagonists. This is the kind of relationship between different species. One of them is a parasite. He uses the other (master) as a power source. In doing so, it imposes on him, in whole or in part, relationships with the environment. Now we know what parasitism is.

If we talk about the groups in which this kind of coexistence occurs, then they are very diverse: animals, protozoa, fungi, bacteria. As a rule, the physiological actions of the parasite are often subordinated to the host. And its life cycle and reproduction strongly depend on obtaining from the biological resources necessary for these actions. If we talk about the degree of parasitism, then the longer the organism exists at the expense of the host, the less will eventually cause harm to the latter. The victim always adapts. What is parasitism, we now know. But let us examine in more detail its main varieties.

Forms

If we talk about what forms of this phenomenon exist, they are also very diverse. Parasites are both animal and vegetable. They differ in that different sources are used to obtain resources: representatives of fauna and flora, respectively. Vegetables according to the official classification are usually called phytoparasites. Most often such are small fungi, less often - bacteria. Now consider the forms of parasitism. There are only two of them.

There is a so-called ectoparasitism and endoparasitism. In the case of the first, the creature lives outside its master and is somehow connected with its skin or other veils. The most striking example of this is ticks or fleas. Both for life, people or animals are needed. They hide either in the hairline, or bite into the skin.

In the case of endoparasitism, the organism lives inside the being, which provides it with all the necessary biological resources. Such forms include protozoa, parasitic worms and others. Strange as it may seem, but it is the second species - life inside the host - that meets much more often ectoparasitism. According to biologists, this is due to the fact that it is easier and easier to inhabit inside, since it is very difficult to detect a pest. It is not accidentally crushed, not smashed, like the same tick or flea.

As a rule, parasites that live inside the host use passive propagation mechanisms. For example, lay the larvae in the grass, then they are eaten together with the vegetation by the animal, and already inside it they hatch. And ectoparasites for propagation use active methods. Also there are necrotic parasites. They differ in that they cause the death of their carrier due to a lack of nutrients. Or he dies because of the toxic substances released by pests in the process of their life.

Superparasites

Superparasites were called so not in vain. Their distinctive features are not in size or distribution. The thing is that they parasitize, being themselves like that. Such a creature lives at the expense of a pest that stays in the animal. Also called a parasite of the second kind. In very rare cases, you can meet such "insolent" third and fourth order!

Predation and parasitism

The distinction between the classification of pure predation and parasitism is rather controversial. And it often causes confusion. Sometimes by this definition we mean any eating of one organism by another, and without killing. Simply put, this is the attitude of the parasite and the host. But we'll still try to figure this out.

As in the case of classical animal predation, the parasite damages the external or internal structure of the host organism. The only purpose of an uninvited invasion is different. If we consider the similarities and differences between predation and parasitism, then the wrecker throughout his life, as a rule, lives on the same owner. He is not interested in his death. True, it does not always happen. Some types of parasites, although they live inside, but their ultimate goal is to devour the victim. For example, this is how larvae of some dipterous insects act.

Also, science knows some animals that can combine a parasitic way of life with a predatory one. Such qualities are possessed by the bugs of the Predatory family. They can eat both other insects and the blood of a person or other warm-blooded animal.

What is the similarity of predation and parasitism?

With all their differences, there is, of course, a similarity. Both parasites and predators live off others. Just the last do it, periodically going on a hunt. So come the lions, tigers, panthers and so on. Others, because of their small size, are forced to eat carefully, placing emphasis on secrecy.