COCKROACH
Cockroaches (or roaches) are a paraphyletic group of insects belonging to Blattodea, containing
all members of the group except termites. About 30 cockroach species out of 4,600 are associated
with human habitats. Some species are well-known as pests.
The cockroaches are an ancient group, with their ancestors, known as "roachoids", originating
during the Carboniferous period, some 320 million years ago. Those early ancestors, however,
lacked the internal ovipositors of modern roaches. Cockroaches are somewhat generalized insects
lacking special adaptations (such as the sucking mouthparts of aphids and other true bugs); they
have chewing mouthparts and are probably among the most primitive of living Neopteran insects.
They are common and hardy insects capable of tolerating a wide range of climates, from Arctic
cold to tropical heat. Tropical cockroaches are often much larger than temperate species.
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