Ethological structure of populations

The ethological or behavioral structure of the population is the system of relationships between members of one population.

Behavior of animals in relation to other members of the population depends primarily on whether a single or group way of life is peculiar to the species.

A single way of life, at which the species of a population are independent and separate from each other, is typical for many species, but only at certain stages of the life cycle. Completely solitary existence of organisms in nature does not occur, since in this case it would be impossible to carry out their basic life function - reproduction. However, some species are characterized by very weak contacts between cohabiting individuals. These are, in particular, individual aquatic inhabitants with an external method of fertilization, in which there is no need to directly meet partners, for example, single actinia.

Family way of life. In the family way of life, the ties between parents and their generation are strengthened. The simplest kind of such connection is the care of one of the parents about the laying eggs: protection of the egg laying, incubation, additional aerating, etc.

In the family way of life the territorial behavior of animals is obviously expressed: various signals, marking, ritual forms of threat and direct aggression ensure possession of a site sufficient for rearing generation.

The larger groups of animals are flocks, herds and colonies. At the heart of their formation lies the further complication of behavioral links in populations.

Colonies. These are group settlements of sedentary animals. They can exist for a long time or arise only for the period of reproduction, as, for example, with many birds - rooks, gulls, loons, puffins, etc. The complexity of the interrelationships between species of the colony of animals is extremely varied - from simple territorial aggregations of single forms to associations, where individual members perform, as organs in a coherent organism, different functions of species life.

The most complex colonies of social insects - termites, ants, bees. They arise on the basis of a greatly expanding family. In such colonies-families insects perform together most of the basic functions: reproduction, protection, provision of food for themselves and their generation, construction, etc.

Flocks (shoals, packs). These are temporary associations of animals that exhibit a biologically useful organization of actions. Flocks facilitate the performance of any function in the life of the species: protection from enemies, getting food, migration. The aggregating behavior is common among birds and fish, as for mammals it is common for many canids. Imitative reactions and orientation toward neighbors are highly developed in the flocks.

Herds. These are longer and more permanent animal associations than flocks. In herd groups, as a rule, all the basic functions of the life of the species are realized: foraging, protection from predators, migration, reproduction, rearing of young animals, etc. The basis of group behavior of animals in herds is the relationship of dominance-subordination based on individual differences between species.

Optimization of physiological processes leading to viability increase in the joint existence, was called the effect of the group. Life in the group through the nervous and hormonal systems is reflected in the course of many physiological processes in the animal's body. Isolated species have changes in metabolic rate, faster usage of reserve substances, viability decrease; they haven't a number of instincts.