The Insects: Structure and Function

Structure and Function......Page 1
Structure and Function......Page 3
Contents......Page 5
Preface......Page 9
Acknowledgments......Page 12
Prologue......Page 13
Outline placeholder......Page 0
Archaeognatha......Page 16
Ephemeroptera......Page 17
Plecoptera......Page 18
Mantodea......Page 19
Grylloblattodea (Notoptera)......Page 20
Dermaptera......Page 21
Phasmatodea......Page 22
Psocoptera......Page 23
Hemiptera......Page 24
Megaloptera......Page 25
Neuroptera......Page 26
Strepsiptera......Page 27
Siphonaptera......Page 28
Trichoptera......Page 29
Hymenoptera......Page 30
Part NaN: The head, ingestion, utilization and distribution of food......Page 33
Introduction......Page 35
1.1.1 Orientation......Page 36
1.1.2 Rigidity......Page 37
1.1.3 Molting......Page 40
1.2 Neck......Page 41
1.3.1 Antennal structure......Page 42
1.3.3 Functions of antennae......Page 44
Recommended reading......Page 45
References in figure captions......Page 46
Introduction......Page 47
2.1.1 Biting mouthparts......Page 48
2.1.3 Sucking mouthparts......Page 51
2.2 Mechanics and control of feeding......Page 54
2.2.1 Biting and chewing insects......Page 56
2.2.2 Fluid-feeding insects......Page 57
2.2.3 Prey capture by predaceous insects......Page 63
2.3 Regulation of feeding......Page 66
2.5.1 Mandibular, hypopharyngeal and maxillary glands......Page 69
2.5.2 Labial glands......Page 71
SummarySummaryThe extraordinary diversity of feeding niches occupied by insects has involved an equivalent diversification of mouthpart structures. The resulting mouthpart designs are all modifications of a common ground plan, involving the same basic ``toolkit´´ of components - labrum, hypopharynx, mandibles, maxillae and labium.The mechanics of feeding involves a complex interplay between the physical and chemical properties of the food and the sensory, neural and motor system responsible for coordinating the movements of the mouthparts.The timing and size of bouts of feeding (meals) is determined by the physiological state of the insect, chemical and mechanosensory cues from the food and negative feedbacks that accrue during and after a m.........Page 75
References in figure captions and tables......Page 76
Introduction......Page 78
3.1.2 The foregut......Page 79
3.1.3 The midgut......Page 80
3.1.4 The peritrophic envelope......Page 84
3.1.5 The hindgut......Page 87
3.1.6 Muscles of the gut......Page 88
3.1.7 Innervation of the gut......Page 90
3.2.1 General patterns in insect digestion......Page 91
3.2.3 Digestion in the gut lumen......Page 94
3.2.4 Protein digestion......Page 95
3.2.5 Carbohydrate digestion......Page 96
3.2.6 Digestion of lipids......Page 101
3.2.7 Variation in enzyme activity......Page 102
3.3.1 Transport of amino acids and protein......Page 104
3.3.3 Transport of lipids and related compounds......Page 105
3.3.5 Absorption of water......Page 106
3.4 The alimentary tract as an immunological organ......Page 109
Recommended reading......Page 110
References in figure captions and table......Page 111
Introduction......Page 113
4.1.2 Amino acids......Page 114
4.1.3 Carbohydrates......Page 115
4.1.4 Lipids......Page 116
4.1.5 Vitamins......Page 118
4.2 Balance of nutrients......Page 119
4.2.1 Changes in nutrient requirements......Page 120
4.2.2 Maintaining nutrient balance......Page 122
4.2.4 Pre-ingestive mechanisms of nutritional regulation......Page 125
4.3 Nutritional effects on growth, development, reproduction and lifespan......Page 127
4.4.1 Symbiotic microorganisms and provision of nitrogen......Page 130
4.4.3 Microorganisms and the sterol nutrition of insects......Page 135
Headings3......Page 136
References in figure captions......Page 137
Introduction......Page 139
5.1.1 The dorsal vessel......Page 140
5.1.2 Sinuses and diaphragms......Page 142
5.1.3 Accessory pulsatile organs......Page 143
5.2.1 Movement of the hemolymph......Page 145
5.2.2 Heartbeat......Page 146
5.3.1 Hemolymph volume......Page 149
5.3.3 Osmotic pressure and osmotically active solutes......Page 151
5.3.4 Hemolymph proteins......Page 153
5.4.1 Types of hemocytes......Page 156
5.4.2 Origin of hemocytes......Page 157
5.4.3 Functions of hemocytes......Page 159
Recommended reading......Page 161
References in figure captions......Page 162
Introduction......Page 164
6.1.1 Trophocytes......Page 165
6.1.2 Urate cells......Page 167
6.1.5 Development and maturation of the fat body......Page 168
6.2.1 Lipids......Page 169
6.2.2 Proteins and amino acids......Page 170
6.2.3 Carbohydrates......Page 171
6.2.4 Mobilization of energy stores......Page 172
6.2.5 Larval energy stores in adults......Page 173
6.3.1 The fat body as an endocrine organ......Page 174
6.3.2 Monitoring nutritional status......Page 175
References in figure captions......Page 176
Part NaN: The thorax and locomotion......Page 179
Introduction......Page 181
7.1 Segmentation of the thorax......Page 182
7.2.1 Tergum......Page 183
7.2.2 Sternum......Page 184
7.2.3 Pleuron......Page 186
Recommended reading......Page 187
References in figure captions......Page 188
Introduction......Page 189
8.1 Structure of the legs......Page 190
8.1.1 Segmentation of the legs......Page 191
8.1.2 Muscles of the legs......Page 193
8.1.3 Sensory system of the legs......Page 194
8.1.4 Attachment devices......Page 196
8.2 Walking and running......Page 198
8.2.2 Patterns of leg movement......Page 199
8.2.3 Coordination of leg movement......Page 201
8.2.4 Stability......Page 204
8.3.1 Jumping with the legs......Page 205
8.3.2 Other mechanisms of jumping......Page 209
8.3.3 Crawling......Page 210
8.4.1 Movement on the surface......Page 212
8.4.3 Swimming with the legs......Page 214
8.4.4 Other mechanisms of swimming......Page 215
8.5 Other uses of legs......Page 217
8.5.2 Grasping......Page 218
8.5.3 Grooming......Page 219
8.5.5 Reduction of the legs......Page 220
SummarySummaryInsects typically have six legs, each containing six segments, the coxa, trochanter, femur, tibia, tarsus and pretarsus. The legs are furnished with a variety of exteroceptors, proprioceptors and chemoreceptors, and most insect orders have evolved smooth or hairy pads as attachment devices.Walking and running movements typically involve the coordinated movements of all six legs. Sensory feedback is important to patterning leg movements, particularly when the required movements are slow or unpredictable. The central nervous system plays an important role in pattern generation, and centrally generated commands may dominate during fast motions. Viscoelastic damping is also important in providing dynamic stabilization of fast movem.........Page 221
References in figure captions......Page 222
Introduction......Page 225
9.1.1 Wing membrane......Page 226
9.1.2 Veins and venation......Page 227
9.1.3 Flexion lines......Page 229
9.1.4 Fold lines......Page 231
9.1.5 Areas of the wing......Page 232
9.1.6 Sensilla on the wings......Page 233
9.1.8 Articulation of the wings with the thorax......Page 234
9.2.1 Wings adapted for flight......Page 236
9.2.2 Halteres......Page 237
9.2.4 Winglessness......Page 238
9.3.1 Types of flight muscle......Page 239
9.3.3 Movements produced by the flight muscles......Page 241
9.3.4 Movements due to elasticity......Page 243
9.3.5 Initiation and maintenance of wing movements......Page 244
9.3.6 Control of wing movements......Page 245
9.4 Wing kinematics......Page 246
9.4.1 Wingbeat frequency......Page 248
9.4.2 Stroke plane angle......Page 250
9.4.4 Wing rotation......Page 251
9.4.5 Wing deformation......Page 252
9.5.1 Leading-edge vortices......Page 253
9.5.2 Rotational lift......Page 254
9.6.1 Fuels for flight......Page 255
9.7 Sensory systems for flight control......Page 257
9.7.1 Vision......Page 258
9.7.2 Airflow sensors......Page 259
9.7.4 Inertial sensors......Page 260
Headings5......Page 262
References in figure captions......Page 263
Introduction......Page 265
10.1.1 Basic muscle structure......Page 266
Synchronous skeletal muscles......Page 269
Asynchronous skeletal muscles......Page 272
Cardiac muscle......Page 273
10.2.1 Mechanics of contraction......Page 274
10.3.1 Innervation......Page 276
Activation of the muscle fiber......Page 278
Activation of the contractile system......Page 280
Neuromodulation......Page 281
Control of visceral muscles......Page 283
10.4.3 Twitch duration......Page 284
10.4.5 Oxygen supply......Page 285
10.5.1 Muscle tonus......Page 286
10.5.2 Locomotion......Page 287
10.6 Changes during development......Page 289
10.6.2 Post-eclosion growth of the flight muscles of holometabolous insects......Page 290
10.6.3 Regressive changes in flight muscles......Page 291
10.6.4 Muscles associated with hatching, eclosion and molting......Page 292
10.6.5 Effects of activity on muscles......Page 294
Recommended reading......Page 295
References in figure captions and table......Page 296
Part NaN: The abdomen, reproduction and development......Page 299
Introduction......Page 301
11.1.2 Structure of abdominal segments......Page 302
11.1.3 Musculature......Page 304
11.2 Abdominal appendages and outgrowths......Page 305
Styliform appendages......Page 306
11.2.2 Larval structures associated with locomotion and attachment......Page 307
11.2.3 Sensory structures......Page 308
11.2.4 Gills......Page 309
11.2.6 Secondary sexual structures......Page 310
11.2.7 Other abdominal structures......Page 311
SummarySummaryThe adult abdomen generally consists of 11 segments plus the telson, which bears the anus. Abdominal segments typically consist of a sclerotized tergum and sternum, and a membranous pleural region. Intersegmental membranes connect adjacent segments, although these may also be fused wholly or in part.The more anterior segments have a spiracle on either side. Genital segments may be highly modified, to form copulatory structures in the male, and in some orders, the ovipositor in the female.There are longitudinal muscles that extend and retract the abdomen, and lateral muscles that compress the abdomen dorso-ventrally. Other muscles are also present that connect with the abdominal appendages, especially the genitalia, and the spir.........Page 312
References in figure captions......Page 313
Introduction......Page 314
12.1 Anatomy of the internal reproductive organs......Page 315
12.2.1 Structure of mature spermatozoa......Page 318
12.2.2 Sperm bundles......Page 320
12.2.3 Spermatogenesis......Page 321
Spermiogenesis......Page 322
Control of spermatogenesis......Page 323
12.3 Transfer of sperm to the female......Page 324
12.3.1 External reproductive organs of the male......Page 325
12.3.2 Pairing and copulation......Page 327
Spermatophores......Page 329
Direct insemination......Page 335
Hemocoelic insemination......Page 336
Sperm capacitation......Page 337
12.4.1 Nutritive effects of mating......Page 338
12.4.2 Enhancement of female oviposition......Page 339
12.4.3 Reduction of females readiness to remate......Page 340
12.4.4 Transfer of other ecologically relevant compounds......Page 341
SummarySummaryThe internal anatomy of the male reproductive tract includes the testes, where sperm are manufactured, the vas deferens and seminal vesicles, where mature sperm are stored, and the ejaculatory duct and accessory glands that secrete proteins that contribute to the seminal fluid.The head of the mature spermatozoa consists of an acrosome and nucleus. The tail consists of the axoneme and mitochondrial derivative.Sperm cysts are produced at the apex of the testis follicle and grow to form spermatocytes as they move through the follicle. Following two meiotic divisions to produce spermatids, they develop into spermatozoa before being shed into the vas deferens and from there move to the seminal vesicle.Insect external genitalia exhib.........Page 342
References in figure captions......Page 343
Introduction......Page 345
13.1 Anatomy of the internal reproductive organs......Page 346
13.2 Oogenesis......Page 349
13.2.1 Types of ovariole......Page 350
13.2.3 Meiosis......Page 354
Patterns of accumulation in the oocyte......Page 355
Yolk proteins......Page 356
13.2.5 Vitelline envelope and chorionogenesis......Page 360
13.2.6 Resorption of oocytes......Page 363
13.3 Ovulation......Page 364
13.4 Fertilization of the egg......Page 365
13.5.1 Female genitalia: the ovipositor......Page 366
13.5.2 Mechanisms of oviposition......Page 368
13.5.3 Control of oviposition......Page 370
13.5.4 Role of the accessory glands......Page 371
SummarySummaryThe internal anatomy of the female reproductive tract includes: the ovaries, where eggs are manufactured; the oviducts through which they pass; and a genital chamber referred to as the vagina and/or bursa copulatrix, into which males deposit their ejaculate. There are one or more spermathecae in which sperm are stored prior to their utilization, and frequently a pair of accessory glands.There are two basic types of ovary - panoistic and meroistic. In panoistic ovaries, ova develop directly from oocytes that have their origins in the germarium. In meroistic ovaries, nurse cells or trophocytes provide content to the developing oocyte. In telotrophic ovaries nurse cells remain in the germarium while in polytrophic ovaries they rem.........Page 375
References in figure captions......Page 376
Introduction......Page 379
14.1 The egg......Page 380
14.1.1 Major structural features of insect eggs......Page 381
14.1.2 Fertilization......Page 383
14.1.3 Respiration......Page 384
14.1.4 Water regulation......Page 385
14.1.5 Water absorption......Page 386
14.1.6 Features of the eggshell that facilitate hatching......Page 388
14.2 Embryogenesis......Page 389
14.2.1 Cleavage......Page 390
14.2.2 Formation of the blastoderm and vitellophages......Page 391
14.2.5 Germ anlage formation......Page 392
14.2.6 Gastrulation and segmentation......Page 393
14.2.7 Formation of embryonic membranes......Page 395
14.2.8 Regulation of segmentation......Page 397
14.2.9 Regulation of dorsal-ventral axis formation......Page 399
Epidermis and the formation of appendages......Page 401
Nervous system......Page 403
Imaginal discs......Page 405
14.2.13 Mesoderm structures and formation of the body cavity......Page 406
Muscles, fat body and hemocytes......Page 407
14.2.16 Transcriptional and translational activity......Page 408
14.2.17 Temporal pattern of embryogenesis among insects......Page 410
Pseudoplacental viviparity......Page 412
Adenotrophic viviparity......Page 413
Hemocoelous viviparity......Page 415
Ovoviviparity......Page 416
Polyembryony......Page 417
14.4 Sex determination......Page 420
14.5.1 Thelytoky......Page 422
14.5.2 Arrhenotoky......Page 423
14.6 Pedogenesis......Page 424
SummarySummaryMost insects are oviparous and lay eggs with a pre-packaged source of nutrients - yolk - that is surrounded by a rigid eggshell with features important for fertilization, respiration and water regulation.Embryogenesis begins with the formation of a zygote nucleus and ends with development and hatching of a nymph or larva. The extraordinary series of events that transpire during embryogenesis are regulated by a multitude of genes that form complex regulatory cascades and signaling pathways.Some insect groups have evolved other strategies for acquiring the nutrients necessary for embryonic development. These include viviparous species whose eggs obtain nutrients from the mother, and a large number of endoparasites whose eggs obta.........Page 425
Recommended reading......Page 426
References in figure captions......Page 428
Introduction......Page 430
15.1.1 Mechanisms of hatching......Page 431
15.1.3 Hatching stimuli......Page 433
15.2 Larval development......Page 435
15.2.1 Types of larvae......Page 438
15.2.2 Heteromorphosis......Page 440
Weight......Page 442
Increase in size of the cuticle......Page 444
Growth of the tissues......Page 446
Control of growth......Page 448
15.3.1 Hemimetabolous insects......Page 449
Pupa......Page 451
Adult epidermal structures......Page 454
Adult muscles......Page 459
Adult nervous system......Page 460
Malpighian tubules......Page 462
Other adult systems......Page 463
Escape from the cocoon or cell......Page 464
Eclosion of aquatic insects......Page 466
Timing of eclosion......Page 467
15.4 Control of postembryonic development......Page 468
15.4.1 Initiation of molting and metamorphosis......Page 469
15.4.3 Control of ecdysis......Page 472
15.4.4 Controlling expansion and sclerotization......Page 474
Castes of social insects......Page 475
Aphid morphs......Page 476
Color, form and behavior......Page 477
15.6.1 Occurrence of diapause......Page 480
Photoperiod......Page 481
Other factors......Page 483
15.6.4 Diapause development......Page 484
15.6.5 Control of diapause......Page 485
SummarySummaryPostembryonic development is divided into a series of stages, each separated from the next by a molt.In hemimetabolous insects the developmental changes that transform a larva into the adult are relatively slight; in holometabolous insects the changes are very marked and a pupal stage is interpolated between the final larval stage and the adult.Most cuticular growth and changes in cuticular form occur when an insect molts. The molt includes two distinct processes: apolysis, the separation of the epidermis from the existing cuticle, and ecdysis, the casting of the old cuticle after the production of a new one. The escape of the adult insect from the cuticle of the pupa or, in hemimetabolous insects, of the last larval stage is k.........Page 486
Headings9......Page 487
References in figure captions......Page 488
Part NaN: The integument, gas exchange and homeostasis......Page 493
Introduction......Page 495
16.1.1 Epidermal cells......Page 496
16.1.2 Oenocytes......Page 497
16.1.4 Membrane organization and junctional contacts......Page 498
16.1.5 Epidermis differentiation......Page 500
16.2 The cuticle......Page 501
16.2.1 Epicuticle......Page 502
16.2.2 Procuticle......Page 503
16.2.3 Pore canals and wax channels......Page 504
16.3.1 Chitin......Page 505
16.3.2 Chitin metabolism......Page 506
16.3.3 Proteins......Page 509
Cuticle-modifying enzymes......Page 510
16.3.4 Lipids......Page 513
16.3.5 Minerals......Page 514
16.4.1 Rigid and hard cuticles......Page 515
16.4.2 Membranous cuticle......Page 517
Elastic cuticles......Page 518
Plasticization of cuticle......Page 519
16.5.1 Changes in the epidermis......Page 520
16.5.3 Digestion of the old endocuticle......Page 523
16.5.4 Ecdysis......Page 524
16.6.1 Formation of the epi- and procuticle......Page 525
16.6.2 Sclerotization of cuticle......Page 526
16.7 Functions of the integument......Page 529
SummarySummaryThe integument has many important functions for insects. It is composed of the epidermis, the basement membrane and the cuticle, which is a highly specialized apical extracellular matrix consisting of chitin microfibrils embedded in a proteinous matrix.The cuticle is a multilayered biocomposite that can be divided into endo-, exo- and epicuticle. The epicuticle is covered with a wax layer that serves for waterproofing. In addition, the wax layer can be impregnated with hydrocarbons important for social communication.Most of the cuticle components are secreted by epidermal cells in a developmentally regulated manner, but some components are added by other cells such as oenocytes. Insect cuticles vary widely in their mechanical p.........Page 530
References in figure captions......Page 531
Introduction......Page 533
17.1.1 Tracheae......Page 534
17.1.3 Tracheal development......Page 535
17.1.4 Distribution of the tracheae within the insect......Page 537
17.1.5 Molting the tracheal system......Page 540
Pneumatization......Page 542
17.2.2 Structure......Page 543
17.2.3 Control of spiracle opening......Page 546
17.4 Respiratory pigments......Page 547
17.5.1 Diffusion......Page 548
17.5.2 Convection......Page 549
17.5.3 Discontinuous gas exchange......Page 553
17.5.4 Variation in gas exchange......Page 556
Gas exchange in flight......Page 557
17.5.5 Control of ventilation......Page 558
17.6.1 Aquatic insects obtaining oxygen from the air......Page 560
Gas exchange via air bubbles......Page 562
17.6.2 Insects obtaining oxygen from the water......Page 563
Tracheal gills......Page 564
Plastron respiration......Page 566
17.6.3 Ventilation in aquatic insects......Page 567
17.7 Insects subject to occasional submersion......Page 569
17.7.1 Spiracular gills......Page 570
17.8 Gas exchange in endoparasitic insects......Page 572
17.9 Other functions of the tracheal system......Page 573
SummarySummaryGas exchange in insects is facilitated by a tracheal system, an air-filled cuticle-lined invagination. While most insects appear to have intracellular hemoglobin, and some groups of insects have hemocyanin in the hemolymph, the dominant pathway of gas exchange is via the air-filled tracheae. The tracheal system provides a lightweight, high-capacity oxygen-delivery system that enables the highest rates of gas exchange in animals, and recovery from anoxia by diffusion.Most insects have spiracles with closing mechanisms that are actively regulated by the nervous system; these respond to oxygen and carbon dioxide levels, and often are coordinated to allow unidirectional flow.\nMost insects utilize convection to move air through the .........Page 574
Recommended reading......Page 575
References in figure captions......Page 576
Introduction......Page 578
18.1.1 Malpighian tubules......Page 579
18.1.3 Sites of ion exchange in aquatic insects......Page 581
18.2.1 Formation of the primary urine......Page 584
18.2.2 Movement of solutes......Page 585
18.2.3 Excretion of ions......Page 586
18.3.1 Terrestrial insects......Page 587
18.3.2 Freshwater insects......Page 588
18.3.3 Saltwater insects......Page 590
18.4 Control of diuresis......Page 591
18.5 Nitrogenous excretion......Page 594
18.5.1 Using genomics to discover metabolic pathways......Page 596
18.5.2 Storage excretion......Page 597
18.6 Detoxification......Page 599
18.7.1 Specialized secretions and light production......Page 601
18.8 Nephrocytes......Page 603
18.9 Water regulation......Page 605
Water loss through the cuticle......Page 606
Water loss from the respiratory surfaces......Page 607
Adaptation to water loss......Page 608
Uptake through the cuticle......Page 609
18.9.3 Water balance......Page 613
SummarySummaryThe basic excretory system is composed of the Malpighian tubules and hindgut, which generate urine and selectively reabsorb water or nutrients, respectively. Some insects lack tubules, or have other specializations (e.g., anal papillae).Urine production is driven by a plasma membrane V-ATPase, combined with exchangers and channels. It is under sophisticated neuroendocrine control.The excretory system also plays key roles in detoxification and metabolism; and in innate immunity.Nephrocytes and macrophage-like hemocytes provide further protection against toxic compounds or foreign material in the hemocoel.Although organismal water balance depends critically on the excretory system, there are a range of physiological and behaviora.........Page 616
References in figure captions and tables......Page 617
Introduction......Page 620
19.1.1 Heat gain......Page 621
19.1.2 Heat loss......Page 625
19.2.1 Behavioral regulation......Page 627
19.2.2 Physiological regulation......Page 628
19.2.3 Regulation of colony temperature by social insects......Page 629
19.3 Performance curves......Page 630
19.4.1 Flight at low temperature......Page 632
19.4.2 Survival at low temperatures (cold hardiness)......Page 633
19.5 Activity and survival at high temperatures......Page 639
19.6 Acclimation......Page 641
19.6.1 Rapid thermal responses......Page 642
19.8 Temperature and humidity receptors......Page 643
19.8.1 Cellular mechanisms of temperature sensation......Page 645
19.9 Temperature-related changes in the nervous system......Page 646
19.10 Large-scale patterns in insect thermal biology......Page 648
SummarySummaryInsects are capable of sensing, integrating and responding to temperature in their environments. Many insects are capable of modifying the environmental temperatures they experience using behavioral or physiological adjustments.Insect performance is a function of body temperature. This function is non-linear and asymmetric. Overheating poses a greater survival threat than cooling an equivalent amount.Insects can survive low temperatures by either allowing or preventing freezing of body fluids. There is considerable diversity within these two general strategies of cold hardiness among insect species.Insects survive high temperatures by using behavioral strategies, having high levels of heat resistance, rapidly developing heat re.........Page 649
References in figure captions and tables......Page 650
Part NaN: Communication......Page 655
Introduction......Page 657
20.1.1 Neuron......Page 658
20.1.2 Glial cells......Page 660
20.2.2 Signal transmission......Page 662
Action potentials......Page 663
Events at the synapse......Page 665
20.2.3 Chemical messengers of neurons......Page 666
Neurotransmitters......Page 668
Neuromodulators......Page 670
Neurohormones......Page 673
20.3.1 Ganglia......Page 674
Motor neurons......Page 675
Interneurons......Page 676
Homologies......Page 678
20.4 Brain......Page 679
Mushroom bodies......Page 680
Central complex......Page 684
Optic lobes......Page 686
20.4.2 Deutocerebrum......Page 689
20.5.1 Integration at the synapse......Page 691
20.5.2 Integration by interneurons......Page 692
20.5.3 Neural mapping......Page 693
20.5.4 Pattern generation......Page 695
20.5.5 Neural basis of learning......Page 696
20.5.6 Rhythms of behavior......Page 699
Headings3......Page 701
Headings9......Page 702
References in figure captions and tables......Page 703
Introduction......Page 706
21.1.3 Peptide hormones......Page 707
Glands producing ecdysteroids......Page 716
Corpora allata......Page 717
Ring gland of cyclorrhaphous Diptera......Page 718
Endocrine cells of the midgut......Page 719
21.2.2 Neurosecretory cells......Page 720
21.4.1 Molting hormones......Page 723
21.4.2 Juvenile hormone......Page 726
21.4.3 Neuropeptides......Page 727
21.5.1 Ecdysteroids......Page 728
21.5.2 Juvenile hormone......Page 730
21.5.3 Peptide hormones and biogenic amines......Page 732
Headings4......Page 735
Headings7......Page 736
Headings9......Page 737
References in figure captions and table......Page 738
Introduction......Page 740
22.1.2 Ommatidial structure......Page 741
Variation of ommatidial structure within species......Page 744
Interspecific variation in ommatidial structure......Page 745
22.2.1 Image formation......Page 747
22.2.2 Resolution......Page 749
22.2.5 Distance perception......Page 750
22.2.6 Visual tracking......Page 752
22.3.1 Transduction......Page 753
22.3.2 Adaptation......Page 755
Regulation of light reaching the receptors......Page 756
Regulation of receptor sensitivity......Page 757
22.3.3 Spectral sensitivity and color vision......Page 759
22.3.4 Discrimination of the plane of vibration (polarization sensitivity)......Page 761
22.4 Dorsal ocelli......Page 763
22.5 Stemmata......Page 764
22.6.1 Dermal light sense......Page 766
SummarySummaryInsects have compound eyes, which in part mediate capacities similar to those of lens eyes in vertebrates, but sometimes with wholly different mechanisms. However, some of the visual abilities of insects are wholly different to those of humans - for example, the sensitivity to polarized and ultraviolet light, and the capacity (found in some insects) for 360 vision.\nCompound eyes typically have relatively poor spatial resolution when compared with vertebrate eyes, which can be compensated in part by relatively higher temporal resolution and rapid scanning of the visual scene.Many components of compound eyes, such as the resolution of the ommatidial array and color vision, show dramatic variation between species and are often exq.........Page 767
References in figure captions......Page 768
Introduction......Page 770
Cuticular components......Page 771
Cellular components......Page 773
23.1.2 Functioning......Page 774
Overall response to stimulation......Page 775
Exteroception......Page 776
Proprioceptors......Page 778
23.2.2 Functioning......Page 780
23.2.3 Distribution and functions in the living insect......Page 782
23.2.4 Femoral chordotonal organs......Page 783
23.2.5 Subgenual organs......Page 784
23.2.6 Johnstons organ......Page 785
Structure and occurrence of tympanal organs......Page 787
Functioning of the tympanal organs......Page 791
Functions of tympanal organs......Page 795
23.3.1 Unspecialized receptors......Page 796
23.3.2 Receptors with accessory structures......Page 798
23.3.3 Functioning of stretch receptors......Page 799
SummarySummaryMechanoreceptors are classified as exteroceptors, interoceptors or proprioceptors. Insects possess a great many mechanoreceptors of many different types which, through their various specializations, underpin the senses of touch, hearing and proprioception.Mechanoreceptive sensilla are comprised of a cuticular structure (which is not always present), one or more sensory neurons and associated sheath cells with the cavities they enclose and the structures they produce. In most cases, the sensory neurons are bipolar, having a single dendrite, but some are multipolar with numerous branching dendrites. Chordotonal organ sensilla are characterized by a structure called a scolopale and are referred to as scolopidia.Mechanoreceptive se.........Page 800
References in figure captions......Page 801
Introduction......Page 803
24.1.1 Olfaction......Page 804
24.1.2 Contact chemoreception......Page 805
24.2 Cellular components......Page 806
24.4.1 Perireceptor events......Page 808
24.4.2 Transduction process and receptor molecules......Page 810
24.4.3 Specificity of response......Page 814
24.4.4 Response to mixtures of chemicals......Page 818
24.4.5 Temporal changes in neuronal responsiveness......Page 819
24.5 Integrating function and behavior......Page 820
24.6.1 The olfactory system......Page 821
24.6.2 The contact chemosensory system......Page 822
Headings4......Page 823
References in figure captions and table......Page 824
Introduction......Page 825
25.2.2 Interference in multilayers......Page 826
25.2.3 Coherent scattering in other structures......Page 832
25.3 Pigmentary colors......Page 833
Pterins......Page 834
Ommochromes......Page 835
Quinone pigments......Page 837
25.4 Color patterns......Page 838
25.5.1 Physiological color change......Page 840
Ontogenetic changes......Page 841
Homochromy......Page 842
25.6 Significance of color......Page 844
Deimatic behavior......Page 845
Deflection marks......Page 846
Mimicry......Page 847
25.6.2 Intraspecific recognition......Page 848
25.7.1 Structure of light-producing organs in Coleoptera......Page 849
25.7.3 Control of light production......Page 851
25.7.4 Significance of light production......Page 852
SummarySummaryThere is a spectacular variety of insect color patterns, such as in the butterflies, dragonflies and beetles. The ways in which butterflies, for example, generate iridescence by physical structures show natures nanotechnology at its best. The way in which pigment patterns are generated by the interaction of morphogens and response thresholds in flies and butterflies has become a model system in evolutionary developmental biology.\n\nInsects use visual color signals in a large variety of behavioral contexts, such as the recognition of mates and conspecific competitors, but also to deter predators - and signals are not always honest, such as in butterflies displaying eyespots and harmless flies mimicking the body coloration of wasp.........Page 853
References in figure captions......Page 854
Introduction......Page 856
26.1.2 Acoustic signals......Page 857
26.2.1 Signals having intraspecific significance......Page 858
Attraction from a distance......Page 859
Signaling physiological state or genetic quality......Page 861
Communication in social insects......Page 862
26.2.2 Signals having interspecific significance......Page 863
26.3.1 Percussion......Page 864
Stridulation in Orthoptera......Page 865
Stridulation in other insects......Page 870
Timbals in Hemiptera......Page 871
Timbals of Lepidoptera......Page 874
26.3.4 Signals produced by the flight muscles......Page 875
26.3.5 Air expulsion......Page 876
26.4.1 Organized patterns......Page 877
26.5 Neural regulation of sound production......Page 879
SummarySummaryMany insects produce air-borne sounds and substrate vibrations in order to transmit information to conspecifics, other insects or even non-insect species.Insect acoustic and vibrational signals contribute to reproductive behaviors by attracting potential mates from a distance, advertising individual quality, signaling physiological state and establishing copulatory readiness. Among other purposes they also serve important functions in territorial behaviors, defense against predators and coordination of social insects behaviors.Insect acoustic signals differ in frequency composition, intensity and temporal patterns. Most sound signals are highly species-specific, especially between sympatric species, and many insects produce dif.........Page 885
Headings6......Page 886
References in figure captions......Page 887
Introduction......Page 889
27.2.1 Sex pheromones......Page 890
27.2.3 Aggregation pheromones......Page 895
27.2.4 Marking pheromones......Page 897
27.2.5 Trail pheromones......Page 898
27.2.7 Pheromones of social insects......Page 901
Division of labor: the role of primer pheromones......Page 902
27.3 Information content of pheromonal signals......Page 906
27.3.1 Lepidoptera......Page 908
27.4.2 Coleoptera......Page 910
27.4.3 Diptera......Page 911
27.4.4 Social insects......Page 913
27.5 Regulation of pheromone production......Page 914
27.6 Perception of pheromones and other infochemicals......Page 915
27.7 Information transfer between species: allelochemicals......Page 917
27.8 Producing, storing and releasing allomones......Page 919
27.9 Allelochemicals used in defense......Page 922
27.10 Mimicry......Page 927
Headings4......Page 930
References in figure captions......Page 931
Index......Page 933