Class Insecta (Arthropoda)

1. Have outer covering known as exoskeleton.
2. Exoskeleton is covered with sensory organs such as compound eye.
3. Insects have ability to fly and can still use legs effectively.
4. Reproduce many young.
5. Short life cycle, numerous egg laying periods.
6. Many insects taste with their feet.
7. Insects are ectothermic.

Insects are small animals which have the body divided into three regions, the head, thorax and abdomen. The insects take in air using tracheae which are a system of tubes placed throughout the body. All insects have four pairs of appendages, one pair on the head and three pairs on the thorax. These appendages are all jointed and usually elongate. Other insects use one or multiple sets of wings in conjunction with their appendages for flight. Insects are transversely segmented meaning their bodies are formed by a succession of ring. The amount of rings is usually around thirteen. Insects change in appearance greatly through the course of their lives. For example they start their lives as larvae and eventually metamorphosize into the insect shapes that are familiar to us.

• Insects form the larger part of the land animals in the world. The number of insect species outnumbers all other terrestrial animals and plants together. Although the insects numerically dominate the land as a group their predominance fades in the aquatic environment.
• Insects can experience pigment changes from eating certain foods or in some cases they can be manufactured by the insect.
• The number of described insects is around 700,000 species and an estimate of the known and unknown species together is around 10,000,000.
• Insects are many times thought to be bad for plants and animals. In many cases this can be true however many species can be beneficial. For example, a flowers success depends on the pollenation by bees.

1. Friedlander, C.P. 1976. The Biology of Insects. New York: Pica Press.
2. Klots, Alexander. 1961. 1001 Questions Answered about Insects. New York: Dover Publications INC.
3. Sharp, David. 1970. Insects. New York: Dover Publications INC.