1

Introduction

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development of MAVs with flapping wings. Hence, the understanding of flight

anatomy is rather essential.

(4)

Excretion is by malpighian tubules. They help in osmoregulation and excretion

and pour their secretions in the midgut (hindgut). Adipose tissue or fat body is

well developed in insects since it supplies large amounts of energy for flight.

Sexes are usually separate. Usually, the external genital aperture of a female

insect is found in the eighth abdominal segment and that of a male in the ninth

segment. Always fertilization is internal. Parthenogenesis and viviparity are

also known.

(5)

Development involves complete metamorphosis having egg-larva-pupa and

adult as in housefly and butterfly. Endocrinal glands play a vital role in postem-

bryonic development. The moulting hormone or ecdysones secreted by protho-

racic glands and juvenile hormone by corpora allata are responsible for the

metamorphic changes.

(6)

Life History: Cockroach has an egg case known as ootheca. It has 16 fertilized

eggs inside. The cockroach is paurometabolous. The development is gradual

through the nymphal stages (five). The nymph resembles the adult except in

size, colour, sexual maturity and lack of wings. The life history of termites is

extremely complicated. For complete metamorphosis, the silkworm is a good

example.

Reference

1. Chari (2014). Bio-aerodynamics of Avian Flight. NDRF, Banglore, India.