The fauna of planet Earth is extremely diverse. In zoology, there are various systematizations of the animal world. Bioorganisms are divided into classes, orders and families. Scientists also identify environmental groups of animals. This is a classification of fauna in relation to environmental conditions. In the article we will consider various groups of animals in relation to natural factors.
Definition
The ecological group of animals is a community of different types of bioorganisms. They are united by the same need for the degree of impact of one or another natural factor. In the process of evolution, different species of animals formed in certain environmental conditions and adapted to them. In this regard, similar anatomical and biological characters are fixed in their genotype.
For example, animals of different classes can live in the aquatic environment: fish, mollusks, marine and river mammals, as well as waterfowl. But all of them are united by their adaptability to life in conditions of high humidity. Therefore, these different species of animals belong to the same environmental group.
Birds, bats, some species of insects and marine fish of the Sarangiformes order can live in the air. At first glance, it seems that there is nothing in common between these classes of animals. But in fact, they all have flight devices in the form of wings that allow them to move in the air. Therefore, they are usually attributed to one environmental group.
Classification
In zoology, environmental groups of animals are distinguished in relation to the following natural factors:
- temperature
- water
- light;
- soil;
- snow cover.
This classification is conditional, since no clear boundaries can be drawn between different eco-groups. So, for example, mammals are isolated in a homoyothermal group. This means that their body, thanks to the developed thermoregulation, is able to function normally both in heat and in cold. However, the northern animals living in the Arctic seas (beluga whale, narwhal, some species of pinnipeds) are not included in this group. They can live only with slight fluctuations in low temperatures. Their physiology is not adapted for existence in warm conditions.
Temperature conditions
The following ecological groups of animals are distinguished in relation to temperature:
- Cryophiles. Otherwise, they are called cold-loving animals. Their body is able to function at fairly low temperatures of air and water. These animals remain active even when their tissue fluids are supercooled. Lowering the temperature of the cells of the body to -10 degrees does not affect the condition of the animals. This group includes worms, arthropods, mollusks and some species of protozoa.
- Thermophiles. These are thermophilic animals in which the body is adapted to live in hot conditions. These include some fish species, spiders and insects. For example, in the hot mineral springs of Southern California, a fish lives - spotted cyprinodone. She lives in waters with a temperature of about +50 degrees.
Different types of bioorganisms can live at different temperatures. On this basis, the following ecological groups of animals are distinguished:
- Homoyothermal. They can exist in conditions of sharp temperature fluctuations. They can tolerate both heat and cold. This group includes birds and mammals. Their body has the ability to independently thermoregulate, thanks to the four-chamber structure of the heart and rapid metabolism. These animals are practically independent of the temperature of the environment.
- Stenothermal. This group of bioorganisms can live only with slight fluctuations in external temperature. Stenothermic animals can be both thermophilic and cold-loving. For example, coral polyps, reptiles and some insects are able to live at a temperature of at least +20 degrees. Salmon fish and arctic animals are most active at temperatures not exceeding zero degrees.
- Poikilothermal. These animals can survive very small fluctuations in external temperature. Their thermoregulation is poorly developed and their metabolism is very slow. Their activity and survival depends entirely on the temperature of the environment. Most fish, reptiles and amphibians belong to poikilothermic animals.
Humidity
Of great importance for animals is air humidity. Evaporation of water from the surface of the body and structural features of the skin depend on this factor. Scientists distinguish the following ecological groups of animals in relation to water:
- Hygrophils. These animals live in areas with high humidity, in wetlands, as well as along the banks of water bodies. This group includes amphibians (frogs, toads), beavers, otters, dragonflies.
- Mesophiles. This is the largest group. Mesophiles prefer to live in medium humidity. These include most of the inhabitants of the middle latitudes: moose, bears, wolves, forest birds, ground beetles, butterflies, etc.
- Xerophiles. These bioorganisms like to live in dry conditions, for example, in desert and steppe natural zones. Animals tolerate the absence of moisture well, they have reduced evaporation of water from the skin. This group includes camels, bustards, ostriches, snakes and monitor lizards.
Shine
The following ecological groups of animals can be distinguished in relation to light conditions:
- Daytime. Most animals belong to this variety. They are most active in daylight, and after sunset are in a state of sleep. For example, many birds wake up only with sufficient light.
- Nightly. This group of animals includes owls and bats. During the day they sleep, and at night they are active. Typically, these animals have well-developed hearing.
- Twilight. These animals are most active at dawn and during evening twilight, when the illumination is slightly reduced. This feature of behavior arose in the process of evolution. This way of life helps them hide from predators. Twilight animals include domestic and wild cats, rodents, kangaroos, as well as many species of beetles and butterflies.
Soil connection
Insects and burrows are classified according to their relationship with the soil. Zoologists distinguish the following ecological groups of animals:
- Geobionts. This is a permanent abode of soil. Most of their lives are in the earth. This group includes moles, earthworms, and some species of primary wingless insects (silverfish, two-tailed, nailed tails).
- Geophiles. These include flying insects. Young and adult individuals spend most of their lives in the air. However, at the stage of larvae and pupae, insects live in the soil.
- Geoxenes. These animals lead mainly a terrestrial way of life, but use the soil as a shelter. This group includes mammals living in burrows, some species of beetles, as well as insects of the orders Tarakanovy and Semi-rigid winged.
- Psammophiles. This class includes insects living in the sands of the desert, for example, ant lion and marble raspberry.
Snow cover
Animals living in winter snowfalls are divided into the following groups in relation to the depth of snow cover:
- Hionophobes. These animals cannot move and earn their own food when the snow cover is too deep. For example, roe deer live only in places where the depth of snow does not exceed 50 cm.
- Chionophiles. This group includes animals that take refuge under the snow from predators and bad weather. Chionophiles include field voles and shrews. In the thickness of the snow cover, these rodents are able to make moves, arrange nests and breed.
