How insects breed: a description of the main methods and interesting facts

In the world there are a huge number of insects, which can be found both in forests and fields, and in a person’s house. Consider how insects breed.

Propagation Features

Insects are characterized by sexual dimorphism, that is, it is quite easy to distinguish between a male and a female in appearance. They have different sizes (in this case, many species of females are several times larger than males), differ in color, length of antennae. In some species of butterflies, females do not have wings.

Communication between heterogeneous representatives of the species occurs in various ways:

• Using behavioral features.
• Sound and color signals.
• In a chemical way - the isolation of pheromones.

In certain species, male and female contact is not required for fertilization; these are lower insects whose habitat is rotten wood or soil. How do insects breed in this case? Males leave droplets of semen on the ground, and females capture them with special organs (genital appendages) located next to the genital openings. This is exactly the way inherent to representatives of the class with incomplete transformation:

• Praying Mantis.
• Cockroaches.
• Bedbugs.

Other insects reproduce by mating individuals of different sexes, this phenomenon is called copulation.

Most of the representatives of the class are characterized by reproduction involving individuals of both sexes, however, exceptions are also found in nature.

Ways

There are five main ways insects reproduce. Information about them is presented in the form of a table.

These are the main methods of reproduction of insects found in nature.

Parthenogenesis

Consider which insects are capable of breeding parthenogenetically. These are stick insects, some species of beetles, scale insects, aphids, many species of wasps, ants and bees.

To such reproduction are capable of:

• Males, in this case, the phenomenon is called arrenotokia.
• Females, we are talking about telitokia.
• Both those and others, it is an amphitokia.

It is customary to distinguish several types of parthenogenesis, the differences of which are presented in the table.

This method of reproduction has adaptive value, in the process an individual of only one sex is occupied, this helps insects survive even in adverse external conditions.

Developmental stages

Consider how insects breed and develop. If the process of reproduction can take place both with fertilization and without it, then the development goes through several stages:

• In an incomplete cycle of transformation, it includes three stages: an egg - a larva - an adult (in science, it is called an adult). In this case, the structural features of the larva practically do not distinguish it from the imago.
• The complete transformation cycle involves four stages: egg - larva - pupa - imago. In this case, larvae differ significantly from adult insects.

These are the phases of insect development . The larva can molt several times, gradually increasing in size.

Egg Features

We examined how insects breed. Now we find out what is the peculiarity of their development in each of the phases.

The eggs of the representatives of the class are covered with two shells, have a very different shape, color and size. Most often in nature there are such forms:

• ball;
• oval;
• hemisphere;
• barrel.

For example, the eggs of butterflies and flies are most often oval, while in bedbugs they are in the shape of an almost regular ball. Most often they are deposited in small groups - egg-laying, but in some species they can be deposited one by one.

Larva classification

By type of larva there are:

• Adults (nymphs) - in insects with incomplete transformation. As previously mentioned, they are not much different from adults, hence the name. Most often lead a lifestyle similar to adults and eat the same.
• Non-imaginative are present in the representatives of the class with a complete transformation. They have a simpler structure of the eyes and limbs than adults, there may be a completely different structure of the mouth.

Non-imaginative, in turn, are divided into three types:

• Campoids - resemble adults, quite active, often predators.
• Worm-shaped. Such larvae are large, their body is practically not divided into departments, legs are short or may be completely absent.
• Caterpillars are distinguished by the presence of several pairs of adnexal legs.

These are the main varieties of larvae of the insect class.

Chrysalis stage

Most often, the transformation of the larva into a chrysalis occurs in the soil, less often - inside or on plants. The insect itself remains motionless, but inside it an intensive process of formation of adult tissue occurs. Toward the end of its development, the pupa becomes very similar to an adult, however, it is still possible to distinguish the pupa from the imago: the latter lack an additional protective shell.

Curious facts

Having learned how insects breed, we will get acquainted with a selection of interesting facts:

• Bees mate only once in a lifetime.
• In mosquitoes, mating occurs in the fall, but the females lay their eggs only in the spring, that is, a rather long time elapses between copulation and fertilization.
• Under certain circumstances, parthenogenetically reproduce almost all insects, with the exception of dragonflies and bugs.
• The process of mating ladybugs can last more than 10 hours.
• After mating, the female mantis often eats up the male in order to make up for the lack of nutrients in the body.

We looked briefly at how insects breed. There are many ways, they help populations survive and spread, despite adverse environmental conditions.