Insect Ecology - An Ecosystem Approach 2nd ed - Chapter 4 doc

... rest and can be exposed sud- denly to startle would-be predators. The margin of the front wings in some sat- urniids are shaped and colored to resemble the heads of snakes (Fig. 4. 11) (Grant 0 0 4- P088772.qxd ... are not significantly different (P > 0.05). Instar 12 345 67Total A/I 0.69 0. 64 0.60 0.55 0 .48 0 .43 0 .41 0. 54 P/I 0 .41 0.26 0.28 0.22 0.25 0.26 0.20 0.23 P/I 0.59 0 .43...

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... of organisms and the 4 1. OVERVIEW 001-P088772.qxd 1/ 24/ 06 10:31 AM Page 4 I. SCOPE OF INSECT ECOLOGY Insect ecology is the study of interactions between insects and their environment. Ecology ... the context of ecosystem structure and function. IV. ECOSYSTEM APPROACH TO INSECT ECOLOGY Insect ecology can be approached using a hierarchical model (Coulson and Cross...

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... limited number of resistance mechanisms that confer cross-resistance to plant defenses and structurally related toxicants and, in some cases, to chemi- cally unrelated compounds (Soderlund and ... parasites and pathogens in the hemo- coel (Tanada and Kaya 1993). Behavioral mechanisms also may be used for pro- tection against pathogens. Insects produce a variety of antibiotic and anticancer .....

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... pollinators, seed predators, and seed dispersers affect ecosystem processes. 40 4 13. POLLINATION, SEED PREDATION, AND SEED DISPERSAL 013-P088772.qxd 1/ 24/ 06 11:03 AM Page 40 4 for caching seeds (J. Brown ... this small-seeded composite became numerically dominant and reduced species diversity. Many plant species have become dependent on animal mutualists for seed dis- persal. Seed and...

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... changes, as described earlier, any change will alter insect abundance and distribution and may increase the incidence of crop pests and vectors of human and animal dis- eases (Stapp et al. 20 04, ... invasive IV. RESPONSES TO ANTHROPOGENIC CHANGES 49 002-P088772.qxd 1/ 24/ 06 10:33 AM Page 49 exposed insects. McCreadie and Colbo (1993) and Adler and McCreadie (1997) reported that siblin...

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... 1– 24 25 49 50– 74 75–99 100– 149 150–199 200 40 0 > ;40 0 Recaptured beetles Distance moved (m) 1999 2000 505 285 156 123 49 40 40 54 19 25 14 31 9 24 77 1 4 FIG. 5.5 Range of dispersal distances from ... Following the appearance of transgenic insect- resistant crop species in the late 1980s, geneti- cally engineered, Bt toxin-producing corn, cotton, soybeans, and potatoes hav...

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... cycling, and/or diversity and abundances of other organisms (Klock and Wickman 1978, Leuschner 1980, Schowalter and Sabin 1991, Schowalter et al. 1991, Seastedt 19 84, 1985, Seastedt and Crossley 19 84, ... 1995, Marquis and Whelan 19 94, Oksanen 1983). Manipulations in multiple-trophic–level systems have shown that a manipulated increase at one predator trophic level causes reduced abundanc...

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... POPULATIONS 191 007-P088772.qxd 1/ 24/ 06 10 :43 AM Page 191 cially of insects, can be found in virtually all “natural” ecosystems on all con- tinents. Many herbivorous insects and mites have arrived on agricultural ... (Fig.7.9).Mound den- sities were significantly highest along dirt roads not covered by forest canopy and lowest along roads covered by forest canopy. Powerline and graveled or...

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... al. 19 94, see Chapter 13). Insects are an important food source for a variety of other organisms. Car- nivorous plants generally are associated with nitrogen-poor habitats and depend on insects ... INTERACTIONS 008-P088772.qxd 1/ 24/ 06 10 :44 AM Page 232 Granivorous ants and rodents frequently partition available seed resources. Ants specialize on smaller seeds and rodents specialize on...

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... particular tolerances to disturbance or postdistur- bance conditions (see Chapter 2). Often, legacies from the predisturbance com- munity (such as buried rhizomes, seed banks, woody litter, and animals ... DYNAMICS –30 40 –50 –60 –70 –80 010203 040 500510152025 –20 –10 0 10 20 30 40 50 K/T meters Percent of leaves damaged # Damage types 207 40 4 149 5 252 259 205 2 34 500 225 209 24...

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