03065nas a2200361   4500008004100000020001400041245006400055210006400119260001200183300001400195490000700209520217200216653001602388653001402404653002202418653001502440653001202455653001402467653001402481653001402495653001702509653001002526653001402536653001002550653003302560653001102593653001602604653001402620653001602634653001102650100001802661856002402679       2011                        eng d  a0269-846300aCurrent trends in the evolutionary ecology of plant defence0 aCurrent trends in the evolutionary ecology of plant defence  c2011///  a420 - 4320 v253 aP>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 species10aCOMMUNITIES10aCOMMUNITY10acommunity ecology10aCOMPLEXITY10aecology10aEVOLUTION10aHERBIVORE10aherbivory10ainteractions10aMODEL10aphylogeny10aplant10aplant-herbivore interactions10aPLANTS10aPOPULATIONS10aRESPONSES10aSPECIFICITY10atheory1 aAgrawal, A.A.  uISI:00028850110001202284nas a2200301   4500008004100000020001400041245012200055210006900177260001200246300001400258490000700272520145900279653001901738653001901757653001601776653001401792653001501806653001101821653001201832653002501844653001601869653001501885653001101900100001701911700001301928700001701941856002401958       2010                        eng d  a1984-467000aHow specialists can be generalists: resolving the "parasite paradox" and implications for emerging infectious disease0 aHow specialists can be generalists resolving the parasite parado  c2010///  a151 - 1620 v273 aThe 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 Disease10aClimate change10aCLIMATE-CHANGE10acoevolution10aEVOLUTION10aHYPOTHESIS10ainsect10aINSECTS10aPHYTOPHAGOUS INSECTS10aSPECIALISTS10aspeciation10atheory1 aAgosta, S.J.1 aJanz, N.1 aBrooks, D.R.  uISI:000277490100001