Insect Ecology - An Ecosystem Approach 2nd ed - Chapter 8 ppsx

... defenses induced by early-season herbivores on later colonists (Fig. 8. 11) (e.g., Harrison and Karban 1 986 , M. Hunter 1 987 , Kogan and Paxton 1 983 , N. Moran and Whitham 1990, Sticher et al. 1997, Van Zandt ... did not decline over time in ant-removal plots.These results reflected a gradual displacement of small-seeded plants (on which ants specialize) by large- seeded plants (on which r...

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... POPULATIONS 185 007-P 088 772.qxd 1/24/06 10:43 AM Page 185 long-distance dispersal and may be less able to recolonize vacant or new habi- tats (resulting from disturbance or climate change) across ... (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 paved roads not...

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... the context of ecosystem structure and function. IV. ECOSYSTEM APPROACH TO INSECT ECOLOGY Insect ecology can be approached using a hierarchical model (Coulson and Crossley 1 987 ). Ecosystem conditions ... However, an ecosystem approach provides a framework for integrating insect ecology with the changing patterns of ecosystem structure and function and for applyin...

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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 ... forest canopy and are carried by wind currents to new areas (Wellington 1 980 ). The distance traveled by wind- or water-dispersed insects depends on several factors, including flow rate and in...

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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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... 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-P 088 772.qxd ... allocated as is K), and 85 Sr (assimilated and allocated as is Ca), became use- ful tools for tracking the assimilation and allocation of nutrients through organ- isms, food webs,...

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... Following the appearance of transgenic insect- resistant crop species in the late 1 980 s, geneti- cally engineered, Bt toxin-producing corn, cotton, soybeans, and potatoes have replaced nontransgenic varieties ... labora- tory experiment with sex-linked mutant genes in Drosophila melanogaster (Peterson and Merrell 1 983 ), mutant and wild-male phenotypes exhibited about the same viability,...

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... cycling, and/or diversity and abundances of other organisms (Klock and Wickman 19 78, Leuschner 1 980 , Schowalter and Sabin 1991, Schowalter et al. 1991, Seastedt 1 984 , 1 985 , Seastedt and Crossley 1 984 , ... following predator removal (Carpenter and Kitchell 1 987 , 1 988 , Dial and Roughgarden 1995, Marquis and Whelan 1994, Oksanen 1 983 ). Manipulations in multiple-trophic–level syste...

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... Brown and Hyman 1 986 ) * on herbaceous plants; ** on woody plants 010-P 088 772.qxd 1/24/06 10:47 AM Page 289 that specialized (monophagous) associations almost disappeared at the bound- ary and have ... 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 litte...

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... (e.g.,terrestrial organisms captured by aquatic animals, detritus, and dissolved organic material entering 330 11. ECOSYSTEM STRUCTURE AND FUNCTION 011-P 088 772.qxd 1/24/06 10: 48 AM Page 330 Seastedt and Crossley ... time-integrated normalized difference vegetation index (NDVI) values for 1 987 (from R. Waring and Running 19 98) . 011-P 088 772.qxd 1/24/06 10: 48 AM Page 322 and Ramak...

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