@article {1067,
	title = {Trade-offs between direct and indirect defences of lima bean (Phaseolus lunatus)},
	journal = {Journal of Ecology},
	volume = {96},
	year = {2008},
	note = {J
SEP},
	month = {2008///},
	pages = {971 - 980},
	abstract = {1. Plant defence theory predicts trade-offs among defence traits as a result of resource limitation or pleiotropic effects. Although theoretically widely accepted, empirical demonstrations of such trade-offs are surprisingly scarce and mechanistic explanations are usually lacking. 2. We quantified cyanogenesis (the release of hydrogen cyanide (HCN)) as a direct defence and the emission of volatile organic compounds (VOCs) as an indirect defence against herbivores. To elucidate whether the trade-offs occur at the genetic or phenotypic level we investigated cultivated and wild-type accessions of lima bean (Fabaceae: Phaseolus lunatus L.) and compared different leaf developmental stages. Genetic relationships among the accessions were studied using amplified fragment length polymorphism (AFLP) analysis. 3. Cyanogenesis and the release of VOCs differed significantly among the accessions and were negatively correlated: high cyanogenic accessions released low amounts of VOCs and vice versa. The same remained true for the ontogenetic stages, since primary leaves of all accessions hardly ever produced HCN at all, yet regularly showed high release rates of VOCs. 4. Low and high cyanogenic accessions of lima bean formed distinct clades in an AFLP-based dendrogram, while wild-types and cultivars did not separate. The first pattern indicates that the underlying defensive syndromes are genetically conserved, while the latter is likely to be caused by a multiple origin of cultivated lima beans or an extensive gene flow among cultivated and wild plants. 5. Synthesis. Trade-offs between cynogenesis and VOC release were obvious both between accessions and at the ontogenetic level, and thus cannot be explained by pleiotropy. We contend that allocation restrictions and/or adaptations to different enemy pressures are most likely to explain why lima bean can invest into cyanogenesis or VOCs, but not both},
	keywords = {ADAPTATION, multiple, PLANTS, theory, TRADE-OFFS},
	isbn = {0022-0477},
	url = {ISI:000258379800015},
	author = {Ballhorn,D.J. and Kautz,S. and Lion,U. and Heil,M.}
}
@article {941,
	title = {Does competition between resources change the competition between their consumers to mutualism? Variations on two themes by Vandermeer},
	journal = {American Naturalist},
	volume = {170},
	year = {2007},
	note = {J
NOV},
	month = {2007///},
	pages = {744 - 757},
	abstract = {How does competition between resources affect the interaction between consumer species that share those resources? Existing theory suggests that high resource competition can lead to mutualism. However, this is based on an analysis that need only apply near equilibrium, and experimental demonstrations of such mutualism are rare. Two alternative approaches to measuring food web mutualism are examined here. These are based on the population level effects of adding or removing a consumer species or on the amount of additional mortality that can be applied to one consumer without excluding it. Both measures suggest that mutualism is likely to be confined to two situations: when overlap in resource use by the consumers is very low and when the consumers are inefficient users of their resources. Competition between resources is also likely to increase the occurrence and magnitude of "hypercompetition" between consumers, where the reduction in population size caused by the introduced consumer is greater than that caused by a consumer that is identical to the resident species. Competition between resources can also increase the negative interaction between consumers by destabilizing the dynamics of the system. Such destabilization can cause negative indirect interactions between specialist consumers having no overlap in resource use},
	keywords = {COMPETITION, DYNAMICS, indirect interactions, interactions, MORTALITY, MUTUALISM, SIZE, theory},
	isbn = {0003-0147},
	url = {ISI:000249981500009},
	author = {Abrams,P.A. and Nakajima,M.}
}
@article {971,
	title = {Current trends in the evolutionary ecology of plant defence},
	journal = {Functional Ecology},
	volume = {25},
	year = {2011},
	note = {J
APR},
	month = {2011///},
	pages = {420 - 432},
	abstract = {P>1. In this essay I summarize current trends in the evolutionary ecology of plant defence, while advocating for approaches that integrate community ecology with specific tests of classic evolutionary hypotheses. Several conclusions emerge. 2. The microevolution of defence is perhaps best studied by reciprocal transplant experiments of differentiated plant populations while simultaneously manipulating the presence of the herbivore(s) hypothesized to be the agent(s) of natural selection. 3. Although there is continued interest in the costs of defence, I argue that some empirical approaches to estimating costs (e.g. genetic engineering) may provide limited insight into evolutionary processes. 4. Essentially all plants employ several different lines of defence against herbivory. It is thus time to abandon searching for single silver bullet traits and the simple trade-off model (where traits are arbitrarily expected to negatively covary across genotypes or species). We still know very little about which trait combinations are most effective and have repeatedly evolved together. Thus, some of our prominent theories (e.g. a predicted trade-off between direct and indirect defence) need to be revised. 5. Studies of the macroevolution of plant defence are enjoying renewed interest due to available phylogenies and analytical methods. Although general trends are not currently surmisable, we will soon have strong case studies evaluating both biotic and abiotic drivers of convergent evolution in defence strategies and the role of defence evolution in the adaptive radiation of plant lineages. 6. The evolution of specificity is proposed as a final frontier in understanding complexity in plant-herbivore interactions. Although it is abundantly clear that plants can deploy highly specific defensive responses that are differentially perceived by herbivore species, how such responses evolve and are physiologically regulated remains an important gap. Relatively straightforward methodologies are now available to close the loop between plant perception of herbivory, hormonal responses, and production of defensive end-products across genotype or species},
	keywords = {COMMUNITIES, COMMUNITY, community ecology, COMPLEXITY, ecology, EVOLUTION, HERBIVORE, herbivory, interactions, MODEL, phylogeny, plant, plant-herbivore interactions, PLANTS, POPULATIONS, RESPONSES, SPECIFICITY, theory},
	isbn = {0269-8463},
	url = {ISI:000288501100012},
	author = {Agrawal,A.A.}
}
@article {958,
	title = {How specialists can be generalists: resolving the "parasite paradox" and implications for emerging infectious disease},
	journal = {Zoologia},
	volume = {27},
	year = {2010},
	note = {J
APR},
	month = {2010///},
	pages = {151 - 162},
	abstract = {The parasite paradox arises from the dual observations that parasites (broadly construed, including phytophagous insects) are resource specialists with restricted host ranges, and yet shifts onto relatively unrelated hosts are common in the phylogenetic diversification of parasite lineages and directly observable in ecological time. We synthesize the emerging solution to this paradox: phenotypic flexibility and phylogenetic conservatism in traits related to resource use, grouped under the term ecological fitting, provide substantial opportunities for rapid host switching in changing environments, in the absence of the evolution of novel host-utilization capabilities. We discuss mechanisms behind ecological fitting, its implications for defining specialists and generalists, and briefly review empirical examples of host shifts in the context of ecological fitting. We conclude that host shifts via ecological fitting provide the fuel for the expansion phase of the recently proposed oscillation hypothesis of host range and speciation, and, more generally, the generation of novel combinations of interacting species within the geographic mosaic theory of coevolution. Finally, we conclude that taxon pulses, driven by climate change and large-scale ecological perturbation are drivers of biotic mixing and resultant ecological fitting, which leads to increased rates of rapid host switching, including the agents of Emerging Infectious Disease},
	keywords = {Climate change, CLIMATE-CHANGE, coevolution, EVOLUTION, HYPOTHESIS, insect, INSECTS, PHYTOPHAGOUS INSECTS, SPECIALISTS, speciation, theory},
	isbn = {1984-4670},
	url = {ISI:000277490100001},
	author = {Agosta,S.J. and Janz,N. and Brooks,D.R.}
}
