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 distinguish ecological groups of animals. This is a classification of representatives of the fauna in relation to environmental conditions. In the article, we will consider different 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 a particular natural factor. In the process of evolution, different types of animals were formed in certain environmental conditions and adapted to them. In this regard, similar anatomical and biological features have been 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 they all have in commonadaptability to life in conditions of high humidity. Therefore, these different animal species belong to the same ecological 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 these classes of animals have nothing in common. But in fact, they all have wing-like flight adaptations that allow them to move through the air. Therefore, they are usually referred to the same ecological group.
Classification
In zoology, ecological groups of animals are distinguished in relation to the following natural factors:
- temperature;
- water;
- light;
- ground;
- snow cover.
This classification is conditional, since it is impossible to draw clear boundaries between different ecogroups. So, for example, mammals are isolated into a homoiothermal group. This means that their body, thanks to the developed thermoregulation, is able to function normally both in heat and in cold. However, northern animals living in the Arctic seas (beluga whale, narwhal, some varieties of pinnipeds) are not included in this group. They can only live with slight fluctuations in low temperatures. Their physiology is not adapted to 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 air temperatures.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 types of protozoa.
- Thermophiles. These are heat-loving animals in which the body is adapted to living in hot conditions. These include some species of fish, spiders, and insects. For example, in the hot mineral springs of Southern California, a fish lives - spotted cyprinodon. She lives in waters around 50 degrees.
Different types of bioorganisms can live in different temperature ranges. On this basis, the following ecological groups of animals are distinguished:
- Homeothermal. Able to exist in conditions of sharp fluctuations in temperature. They can tolerate both heat and cold. This group includes birds and mammals. Their body has the ability to self-regulate, due to the four-chamber structure of the heart and a fast metabolism. These animals are practically independent of the external temperature.
- Stenothermal. This group of bioorganisms can live only with slight fluctuations in external temperature. Stenothermic animals can be both heat-loving 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 below zerodegrees.
- Poikilothermic. These animals can survive with very small fluctuations in external temperature. They have poorly developed thermoregulation and a very slow metabolism. Their activity and survival is completely dependent on the temperature of the habitat. Poikilothermic animals include most fish, reptiles and amphibians.
Humidity
Humidity is of great importance for animals. The evaporation of water from the surface of the body and the structural features of the skin depend on this factor. Scientists distinguish the following ecological groups of animals in relation to water:
- Hygrophiles. 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 conditions. These include most of the inhabitants of 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 lack of moisture well, they have reduced evaporation of water from the skin. This group includes camels, bustards, ostriches, snakes and monitor lizards.
Light
The following ecological groups of animals can be distinguished in relation to light conditions:
- Daily. This variety includes mostanimals. They are most active in daylight, and after sunset they are in a state of sleep. For example, many birds only wake up when there is enough light.
- Night. This group of animals includes owls and bats. They sleep during the day and are active at night. Usually such animals have well-developed hearing.
- Twilight. These animals are most active at dawn and during the evening twilight, when the illumination is somewhat reduced. This feature of behavior arose in the process of evolution. This way of life helps them hide from predators. Crepuscular animals include domestic and wild cats, rodents, kangaroos, and many species of beetles and butterflies.
Connecting with the soil
Insects and burrowing mammals are classified according to their association with the soil. Zoologists distinguish the following ecological groups of animals:
- Geobionts. These are the permanent dwellings of the soil. Most of their life takes place in the ground. This group includes moles, earthworms and some types of primary wingless insects (silverfish, two-tailed, springtails).
- Geophiles. These include flying insects. Most of their lives, juveniles and adults spend in the air. However, at the stage of larva and pupa, insects live in the soil.
- Geoxens. These animals lead a predominantly terrestrial lifestyle, but use the soil as shelter. This group includes mammals living in holes, some species of beetles, as well as insects of the orders Cockroaches and Hemiptera.
- Psammophiles. This class includes insects that live in the desert sands, such as the ant lion and marble beetle.
Snow cover
Animals living in conditions of winter snowfall are divided into the following groups in relation to the depth of snow cover:
- Chionophobes. These animals cannot move and forage for themselves when the snow cover is too deep. For example, roe deer live only in places where the snow depth does not exceed 50 cm.
- Chionophiles. This group includes animals that take shelter under the snow from predators and bad weather. Chionophiles include voles and shrews. In the thick of the snow cover, these rodents are able to make passages, build nests and breed.
Sea life
Classification of marine animals (hydrobionts) has its own characteristics. Depending on the depth and localization of their habitat, they are divided into the following groups:
- Pelagic organisms. They live in the water column.
- Benthos. This group includes the inhabitants of the seabed.
Among pelagic organisms, the following subgroups are distinguished:
- Nekton. These are animals that are able to move in water. They have developed organs of movement, and the body has a streamlined shape. Nekton includes large animal species: fish, marine mammals (whales, pinnipeds) and cephalopods.
- Zooplankton. These are pelagic organisms that cannot move independently in the water and resist the current. They are carried by watermasses. Most often, among zooplankton, you can find small crustaceans, as well as larvae of small marine animals. They serve as food for nekton organisms.
Benthos are animals that slowly move along the bottom or dig the ground. Their large concentrations are noted in shallow water. Coelenterates, brachiopods, mollusks, ascidians, and worms most often live at the bottom. For example, such animals of the Black Sea as marble crabs, mussels, sea sponges and sea anemones belong to benthos.
Hydrobionts make up a single biosystem (hydrobiocenosis). All animals living in the marine environment are interconnected. A decrease in the zooplankton population leads to a decrease in the number of fish, as they are deprived of a source of food. And the destruction of benthic fauna and flora has a negative impact on the life of pelagic organisms.
