the insects an outline of entomology

... 25 2 The importance, diversity, and conservation of insects Curiosity alone concerning the identities and lifestyles of the fellow inhabitants of our planet justifies the study of insects. Some of ... phytophagous insects. Another explanation for the high species numbers of insects is the role of sexual selection in the diversifica- tion of many insects. T...

Ngày tải lên: 06/07/2014, 15:31

... 2 The importance, diversity, and conservation of insects Curiosity alone concerning the identities and lifestyles of the fellow inhabitants of our planet justifies the study of insects. Some of ... First, we outline the field of entomology and the role of ento- mologists, and then introduce the ecological functions of insects. Next, we explore insect divers...

Ngày tải lên: 06/07/2014, 15:35

... ii Third Edition The Insects An Outline of Entomology P.J. Gullan and P.S. Cranston Department of Entomology, University of California, Davis, USA With illustrations by K. Hansen McInnes TIA01 ... namely the ecology of ground-dwelling, aquatic and plant-feeding insects, and the behaviours of sociality, predation and para- sitism, and defence. Finally, aspects of m...

Ngày tải lên: 06/07/2014, 22:20

... First, we outline the field of entomology and the role of ento- mologists, and then introduce the ecological functions of insects. Next, we explore insect diversity, and then discuss how we name and ... past and some continuing cultural and economic aspects of insects, their aesthetic and tourism appeal, and their import- ance as foods for humans and animals. We conclude w...

Ngày tải lên: 06/07/2014, 22:20

... lip” (Fig. 2.10). The labrum forms the roof of the preoral cavity and mouth (Fig. 3.14) and covers the base of the mandibles; it may be formed from fusion of parts of a pair of ancestral appendages. ... crickets, and earwigs, the mouthparts are of a biting and chewing type (mandibulate) and resemble the probable basic design of ancestral pterygote insects more c...

Ngày tải lên: 06/07/2014, 22:20

... 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 related to the dis- tance of diffusion ... circulation, the tracheal system and gas exchange, the gut and diges- tion, the fat body, nutrition and microorganisms, the excretory system and waste disposal,...

Ngày tải lên: 06/07/2014, 22:20

... membrane, such that one half closely connects with the anterior and the other half with the posterior tympanal membrane. The primary route of sound to the tympanal organ is usually from the acoustic ... organ in the tibia approximates the function of a horn and amplifies the sound. Although the slits of the tympanic chambers do allow the entry of sound, their e...

Ngày tải lên: 06/07/2014, 22:20

... – the 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 ... messengers) and also control the synthesis of two groups of insect hormones – the ecdysteroids and the juvenile hormones (JH). More detailed discussions of...

Ngày tải lên: 06/07/2014, 22:20

... in insects is the result of the large amount of yolk in the egg. The blastoderm usually gives rise to all the cells of the larval body, whereas the central yolky part of the egg provides 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 measur...

Ngày tải lên: 06/07/2014, 22:20

... 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, ... moderate-sized, soft-bodied insects with anteriorly projecting mandibulate mouthparts and the compound eyes are either reduced or absent. The antennae are multisegmented and...

Ngày tải lên: 06/07/2014, 22:20