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Although behavioral resistance remains enigmatic, an examination of the literature firmly supports the existence of behavioral resistance in both the presence and absence of the better understood and accepted physiological and biochemical mechanisms. Studies of pyrethroid resistance in the horn fly and the tobacco budworm have identified several resistance mechanisms, including behavioral adaptations, in addition to target‐site insensitivity and enhanced detoxification. The coexistence of physiological and behavioral responses neither precludes a common mechanism nor requires one. Even if a common mechanism such as knockdown resistance or enhanced detoxification is involved, this does not negate the survival benefit of either avoiding the toxicant or reducing movement to avoid exposure. Thus, behavioral resistance may be much more ubiquitous and important than previous interpretation of the literature suggests.

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On the occasion of the Ecological Society of America's centennial, we sought to learn which ecological concepts members value in terms of their utility. This required defining “concept,” and selecting concepts from current ecology textbooks that might arguably belong to a normative set. All ESA members were invited to participate in an online survey in October 2014 in which they rated 70, randomly selected concepts (out of a total set of 131) in terms of utility. Alternative to rating, respondents could mark the concept as unfamiliar. Respondents were also able list concepts that were important to them that were not encountered in the survey. Fifteen percent (1324) of the ESA membership participated in the survey. Of these, 89% were addressed in North America, 62% were male, 77% held Ph.D. degrees, 67% were involved in academia through employment or as students, and about one‐half of the total were divided between community and ecosystem ecology domains of interest. The 10 highest ranked concepts (in descending order) for utility were scales (small, local, regional, global, etc.), ecosystem, habitat, species, disturbance/perturbation, organism, population, community, competition, and species life history. The 10 lowest ranked concepts (in descending order) for utility were Lotka‐Volterra predator–prey/competition models, Allee effect, nutrient spiraling, character displacement, doubling time, climax, Hardy‐Weinberg equation, red queen hypothesis, chemoautotroph/chemoautotrophy, and mimicry. Respondents entered 2800 terms not encountered in the survey. After parsing for concepts missed due to the survey's random presentation process, for semantic redundancy and for terms deemed non‐concepts, 119 candidate concepts emerged. Many of these deserve consideration for inclusion in a normative set and introduction in textbooks. This research provides a well‐considered definition of “concept,” a basis for defining a normative set of concepts expected to be known to all ecologists, and a measure of familiarity but, more importantly, a measure of usage by contemporary ecologists who were members of ESA. These results help us to understand ourselves and our science, to better teach ecology, to guide the initiatives of the collective ecological community, and to further explore the extent and intellectual structure of the principal concepts by which ecologists pursue their work.

Sexually mature males of the sourthern green stink bug, N. viridula, release a pheromone attractive in the field to conspecific females, males, and late‐stage larvae and to the parasitoid Trichopoda pennipes (Diptera: Tachinidae). The pheromone blend typically includes (Z)‐α‐bisabolene (17%), trans‐ and cis‐1,2‐epoxides of (Z)‐α‐bisabolene (44 and 15%, respectively), (E)‐nerolidol (1.4%), and n‐nonadecane (7.4%). The existence of Nezara pheromone strains, first suggested by differential Trichopoda parasitization of geographically isolated N. viridula populations, has been chemically verified.

Summary1. Rangeland grasshopper movement was studied in Wyoming, USA, with respect to the biological and ecological factors (population density, developmental stage and weather) in¯uencing net displacement and directionality. 2. A novel adaptation of the mark±recapture method was developed to monitor grasshopper dispersal. The method used¯uorescent powder and resighting marked grasshoppers in the ®eld with ultraviolet light, rather than physical recapturing of individuals. 3. Rangeland grasshoppers exhibited a strong tendency for directional movement. Adult grasshoppers demonstrated a signi®cant tendency for dispersal in a northwesterly direction across a range of population densities (5±8, 10±15 and r 18 grasshoppers m ±2 ). Although not a de®nitive explanation, weather might have in¯uenced this behaviour, as the grasshoppers consistently moved upwind. 4. The mean displacement of grasshoppers in a 36-h period ranged from 2´3 m in nymphs to 3´7 m in adults, with the distance of displacement being positively correlated with population density.5. An understanding of grasshopper movement in terms of directionality and displacement has immediate applicability to reduced agent±area treatments for rangeland grasshopper management.

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