Some insects are capable of sponging, as in the housefly. One of the mouthparts is specialized
for this function, where liquid food is channeled to the esophagus. The housefly is able to
eat solid food by secreting saliva and dabbing it over the food item. As the saliva dissolves
the food, the sponging mouthpart absorbs the liquid food.
Reproduction and Life Cycle of Insects
Most insects have a high reproductive rate and can rapidly reproduce within a short period
of time. With a short generation time, they evolve faster and can adjust to environmental
changes faster. Although there are many forms of reproductive organs in insects, there is
a basic design and function for each reproductive part. These parts may vary in shape
(gonads), position, and number (glands), with different insect groups.
Most insects reproduce via sexual reproduction. The female produces eggs, which are fer-
tilized by the male, and then the eggs are usually deposited in a precise microhabitat at or
near the required food. Most insects areoviviparous, where the young hatch after the eggs
have been laid. In some insects, there is asexual reproduction and in the most common type,
the offspring are essentially identical to the mother. This is most often seen in aphids and
scale insects.
An insect can have one of three types of metamorphosis and life cycle: