‘entomon' and `logos'; ‘entomon’



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Concept & Historical

Development



of Insects
What is Entomology ?
Broadly Entomology is the branch of zoological science which deals with insects. The word Entomology derived from two Greek words entomon' and `logos'; entomon means insects and `logos' means discourse (Av‡jvPbv). The main aim of Entomology is to understand the insects' body organization , functions, habits, behavior, relations to other components of the surrounding environment, their classification, development, distribution, origin, pest history ,economic importance etc.
What is Insects?
Insect are Arthropods (mwÜc`) with distinct head, thorax and abdomen with a pair of antennae, three pair of working legs confined to the thorax and one or two pairs of wings. the integument is hardened into exoskeleton covering with body muscles.
Shape of Insects:
The shape of Insects vary very much. Some insect are spherical, others are flattened like a leaf or elongated like a stick, others have bizarre(wK¤~¢ZwKgvKvi) shape and are clothed with hairs, scales, spines, horns and other grotesque appendages.

Origin of Insects:
The origin of insects date back to about 35,00,00,000 years on the basis of our understanding of arthropod morphology, the myriapods appeared to be closely related insects. Evidence of this is seen from the fact that the first instars of many diplopod myriapods shows many features in the common with insects.




Several other theories have been put forwarded about the origin of insects. Handlirsch's Trilobite theory suggests that the insects have developed from marine ancestors ,the Trilobites (Three lobes: a fossil marine arthropod that occurred abundantly during the Palaeozoic era, with a carapace (‡Lvjv) over the forepart, and a segmented hind part divided longitudinally into three lobes.). This theory has no standing today.

Other theories of marine origin of insects were those of Hansen , who advocated that the insect originated from




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