The Insects - Outline of Entomology 3th Edition - Chapter 17 docx

... when the apex of the point is directed away from the person mounting. For most very small insects, the tip of the point should contact the insect on the vertical side of the thorax below the wings. ... base of the triangle and the insect is then glued to the tip of the point using a minute quantity of water-soluble glue, for example based on gum arabic....

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... numbers of insects is the role of sexual selection in the diversifica- tion of many insects. The propensity of insects to become isolated in small populations (because of the fine scale of their ... classification and their roles in our economic and wider lives. First, we outline the field of entomology and the role of ento- mologists, and then introduce the...

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... defensive and other com- pounds are products of the epidermis, which is a near- continuous, single-celled layer beneath the cuticle. Many of these compounds are secreted to the outside of the insect ... pair of gonostyles (the third valves) derived from the distal part of the appendages of segment 9 (and homo- logous with the styles of the apterygotes mentioned...

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... by the plant. By comparison, a macerate-and-flush strategy is typical of Heteroptera, such as mirids and coreids. These insects disrupt the tis- sues of plants or other insects by thrusting of the ... to be the primary mechanism for the movement of gases in the tracheae and is always the sole mode of gas exchange at the tissues. The efficiency of diffusion is...

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... across. The field of view of each ommatidium differs from that of its neigh- bors and together the array of all ommatidia provides the insect with a panoramic image of the world. Thus, the actual ... insensitive to the wing tone of males of their species. Neither can the male detect the wing tone of immature females – the Johnson’s organ in his antenna respond...

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... transfer of sperm via the insertion of part of the male’s aedeagus (edeagus), the penis, into the repro- ductive tract of the female. In males of many species the extrusion of the aedeagus during ... oviposition in insects. 5.1 BRINGING THE SEXES TOGETHER Insects often are at their most conspicuous when syn- chronizing the time and place for mating. The flas...

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... further discus- sion of the actions of eclosion hormone). Apolysis at the end of the fifth larval instar marks the beginning of a prepupal period when the developing pupa is pharate within the ... affects the eggs of the next generation. The ability of insects to recognize seasonal photo- period and other environmental cues requires some means of measuring tim...

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... as wings held roof-like over the abdomen, fore wings either membranous or in the form of tegmina of uni- form texture, and with the rostrum arising ventrally close to the anterior of the thorax, ... or mistaken. The fore-wing-derived halteres of strep- sipterans are gyroscopic organs of equilibrium with the same functional role as the halteres of Diptera (although...

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... complex circulation of air through the passageways of the nest, as illustrated for the above-ground nest of the African Macrotermes natalen- sis in Fig. 12.10. The origin of the mutualistic relationship ... farming by leaf-cutter ants The subterranean ant nests of the genus Atta (15 spe- cies) and the rather smaller colonies of Acromyrmex (24 species) are amongst...

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... hundreds of kilometers from shore in the Pacific Ocean. The dis- tribution of these insects coincides with mid-oceanic accumulations of flotsam, where food of terrestrial origin supplements a diet of ... proponents of the pre- ferred exite–endite theory speculate that the progenitor of the pterygotes had aquatic immature stages. Support for the latter hypothesis app...

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