Insect Ecology - An Ecosystem Approach 2nd ed - Chapter 3 docx

... parasites and pathogens in the hemo- coel (Tanada and Kaya 19 93) . Behavioral mechanisms also may be used for pro- tection against pathogens. Insects produce a variety of antibiotic and anticancer ... 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...

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... hierarchical approach offers a means of integrating evolutionary and ecosystem approaches to studying insect ecology. The evolutionary approach IV. ECOSYSTEM APPROACH TO INSECT ECOLOGY 11 001-P088772.qxd ... However, an ecosystem approach provides a framework for integrating insect ecology with the changing patterns of ecosystem structure and function and for appl...

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... locations. Although ants and rodents are best known 39 4 13. POLLINATION, SEED PREDATION, AND SEED DISPERSAL 0 1 3- P088772.qxd 1/24/06 11: 03 AM Page 39 4 systems than in gymnosperm-dominated ecosystems, ... only 5 m significantly increased seed survival to nearly 40% over a 7-month period (Fig. 13. 7). C. Chapman and Chapman (1996) compared fruit and seed disappearance and sur- vival of...

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... environmental 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 ... invasive IV. RESPONSES TO ANTHROPOGENIC CHANGES 49 002-P088772.qxd 1/24/06 10 :33 AM Page 49 exposed insects. McCreadie and Colbo (19 93) and Adler and McCreadie (1997) reported that sibling sp...

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... 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 004-P088772.qxd ... perceived to be of special concern because of the recognized importance of these organisms to human health and crop production. Radioactive isotopes, such as 31 P, 137 Cs (assimila...

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... labora- tory experiment with sex-linked mutant genes in Drosophila melanogaster (Peterson and Merrell 19 83) , mutant and wild-male phenotypes exhibited about the same viability, but mutant males ... Following the appearance of transgenic insect- resistant crop species in the late 1980s, geneti- cally engineered, Bt toxin-producing corn, cotton, soybeans, and potatoes have replaced nontransg...

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... 1.00 Stable equilibria 100.0% Invariant loops 27.0% 5-cycles 23. 0% 2-cycles 73. 0% Chaos 83. 5% Chaos 39 .1% Chaos 1.9% Chaos 0 .3% 8-cycles 99.8% 3- cycles 100.0% 3- cycles 45.1% Other cycles 37 .9% 1 3- cycles 29.9% 19-cycles 7.1% 6-cycles 54.9% Other cycles 9 .3% Other cycles 68.2% FIG. ... exposure to altered temperature and moisture (Seastedt and Cross- ley 1981a).Anthropoge...

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... “natural” ecosystems on all con- tinents. Many herbivorous insects and mites have arrived on agricultural or forestry products and become plant pests in agroecosystems or forests.Some her- bivorous and ... ornamental plants and their associated exotic insects and pathogens. Exotic or native ornamental species usually are stressed by soil com- paction, air and water pollutants, elevated urban...

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... displacement of small-seeded plants (on which ants specialize) by large- seeded plants (on which rodents specialize) in the absence of rodents. Ant removal led to higher densities of small-seeded species, ... 1994, 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...

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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 ... increased grass growth,and subsequently declined, as the abundance of forbs increased. Schowalter (1994, 1995), Schowalter and Crossley (1988), and Schowalter and Ganio (20 03) reported t...

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