insect-papilio-1

insect-papilio-1 - is very acute but in butterflies it is...

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The citrus swallowtail butterfly - Papilio demodocus Papilio demodocus is a butterfly, common in sub-saharan Africa. It is most abundant during the rains when its larvae (caterpillars) may cause damage to citrus trees. The body consists of a distinct head, thorax and abdomen, with three pairs of walking legs and two pairs of wings attached to the thorax. The head bears a pair of compound eyes , each with about six thousand separate lenses. The compound eyes are chiefly detectors of movement and pattern, also acting as direction finders. There is little evidence that the insect eye sees a distinct image of the kind seen by a mammalian eye. They are therefore useful in helping the insect to recognize shapes of flowers, or wing patterns of the same species of butterfly, and for detecting the wing movements or sudden approach of predators. On the head there is also a pair of long antennae which bear organs of smell. In moths this sense
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Unformatted text preview: is very acute but in butterflies it is often reduced, probably because their day-flying habits enable visual navigation. The proboscis is a fine tube which is used to suck up nectar or other fluids. When not in use the proboscis is coiled beneath the head. The feet carry taste receptors. If the butterfly lands on a suitable fluid, the proboscis uncoils. The head, body and legs are clothed with hairs, which are flattened and modified on the wings to form overlapping, pigmented scales, giving the wings their characteristic pattern. The scale colour may be produced by a bending of light rays through the scales so that they act like tiny prisms, or by pigment in the scales. The forewings overlap the hind wings so that in flight both pairs move together. Dr. N. Jago compound eye antenna coiled proboscis Papilio head leg antenna compound eye fore-wing hind-wing abdomen thorax Papilio demodocus D.G. Mackean...
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This note was uploaded on 11/29/2011 for the course BIO 218 taught by Professor Young during the Fall '11 term at BYU.

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