INSECTS

Reproduction

Most species of insects have males and females that mate and reproduce sexually. In some cases, males are rare or present only at certain times of the year. In the absence of males, females of some species may still reproduce. This is common, particularly among aphids. In many species of wasps, unfertilized eggs become males while fertilized eggs become females. In a few species, females produce only females.

A single embryo typically develops within each egg, except in the case of polyembryony, where hundreds of embryos may develop per egg. Insects may reproduce by laying eggs or, in some species, the eggs may hatch within the female which shortly thereafter deposits young. In another strategy common to aphids, the eggs hatch within the female and the immatures remain within the female for some time before birth.

Eggs
There is great variety in the eggs of insects, in the shapes and manner of deposition. The shell is chiten and varies in thickness, hardness, texture and color. It may be laid bare and singly, exposed in clusters, enclosed in a structure of some material, inserted into the ground or plant or animal materials, deposited on or in water, deposited on a surface or suspended on a pedistal.