Insects (Class Insecta) are arthropods, having a hard exoskeleton, a three-part body (head, thorax, and abdomen), three pairs of jointed legs, compound eyes, and two antennae. They are the most diverse group of animals on the planet and include more than a million species that are already described. Insects represent more than half of all known living organisms. The number of extant species is estimated at between six and ten million, and potenti...
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Insects (Class Insecta) are arthropods, having a hard exoskeleton, a three-part body (head, thorax, and abdomen), three pairs of jointed legs, compound eyes, and two antennae. They are the most diverse group of animals on the planet and include more than a million species that are already described. Insects represent more than half of all known living organisms. The number of extant species is estimated at between six and ten million, and potentially represent over 90% of the differing life forms on Earth. Insects may be found in nearly all environments, although only a small number of species occur in the oceans, a habitat dominated by another arthropod group, the crustaceans.
Adult modern insects range in size from a 0.139 mm (0.00547 in) fairyfly (Dicopomorpha echmepterygis) to a 56.7-centimetre (22.3 in) long stick insect (Phobaeticus chani). The heaviest documented present-day insect was a 70 g (2½ oz) Giant Weta, though the Goliath beetles Goliathus goliatus, Goliathus regius...
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