Robert Poulin

..This suggests that with most differences in aggregation among samples already explained, there may be little point in seeking universal causes for the remaining variation...

..However, the power of animal personality and behavioural syndromes to inform research on host manipulation by parasites will only be fully realised when underlying mechanisms are elucidated and linked to their phenotypic impacts...

..Therefore, either the historical adoption of a migratory strategy in some Galaxias was an adaptation against parasitism, or it evolved for other reasons and now provides protection from infection as a coincidental side-effect...

..These findings illustrate the ways in which phylogenetically based comparative methods can contribute to biogeographic research...

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..Our results suggest that the dynamics of competition between coinfecting parasites, although influenced by numerous external factors, is also modulated by genetic relatedness among parasites...

..The presence of a large number of infected snails and tidal mixing of cercariae prior to infection results in crabs potentially harbouring hundreds of parasite genotypes despite the crabs' territorial behaviour...

..Host spawning events are likely to be an avenue of egg dispersal for this progenetic species, with the adoption of progenesis being conditional on whether or not the parasite can benefit from fish spawning...

..These results show that the life history strategy adopted by a parasite may be influenced by other parasites sharing the same host...

..Still, these results suggest that host specificity may have tended to decrease in many flea lineages, a process that could have been driven by the benefits of exploiting a wide range of host species...

..With global environmental stressors predicted to enhance trematode infections, our results show that parasite-induced malformation, and its population-scale impacts, could be more widespread than previously considered...

..The results also support the role of the second intermediate host as an accumulator of genetic diversity in the trematode life cycle...

..The indices presented here capture essential features of resource use in parasite communities, and can be useful tools for comparative analyses...

..Host properties like habitat preference, and parasite traits, particularly those related to transmission mode can influence the strength of the observed gradient, as may other environmental and biotic factors...

..These relationships also suggest that adult size is to some extent determined by cystacanth size, and that the characteristics of the definitive host are not the sole determinants of parasite life history traits...

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..The present study is the first to compare life cycle strategies among parasite populations, providing insight into the often unrecognized plasticity in parasite developmental strategies and transmission...

..Furthermore, the data give a rare detailed view of Allee effects in colonization dynamics and suggest that Allee effects may dampen the spread of parasites in a coastal marine ecosystem...

..in A. crassa. Overall, the different parasite species make different use of available crustacean intermediate hosts and possibly contribute to intertidal community structure...

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..Possible alternative reasons for the pattern of positive association between the gymnophallid and the echinostomes are proposed...

..Consequently, a trade-off between size and numbers is possibly imposed by external forces influencing host size, hence limiting physical space or other resources available to the parasites...

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..These findings highlight the often unrecognised plasticity in parasite developmental and transmission strategies...

..This method should be extremely useful for experimental studies using trematode-host systems as models for addressing a range of ecological and evolutionary questions...

..It also summarizes the first findings to emerge from network analyses of host-parasite interactions and identifies promising future directions made possible by this approach...

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..75, suggests that parasites are not like host tissues: they are able to appropriate more host resources than expected from metabolically derived host growth rates...

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..This conclusion supports the view that the biological features of parasite species can potentially override local environmental conditions in driving parasite population dynamics...

..novaezealandensis were most successful. This implies the non-reproducing morphs provide a fitness benefit to Philophthalmus sp. colonies even in the absence of competition, although the nature of this advantage remains unclear...

..The use of the index in comparative studies may help in determining whether interactive helminth communities are, as widely believed, more common in endothermic vertebrate hosts than in fish hosts...

..This review uses several well-known pathogens to demonstrate how host manipulation by parasites is potentially important in epidemiology...

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..Our results shed light on the conditions that may favour switching among intermediate hosts in digeneans, and on the presence/absence of host specificity in these parasites...

..The phylogenetic analytical framework adopted here should allow these questions to be tackled once the necessary data become available...

..If the number of parasite species exploiting a host population is not regulated by processes arising from within the parasite community, external factors such as host characteristics may be the main determinants of parasite diversity...

..There may be some general, large-scale processes acting to structure helminth communities, but local or seasonal influences can often either mask their action, or play more important roles themselves...

..The results suggest that the anemone-cockle symbiosis is a non-obligate mutualistic relationship in which the former is provided with a suitable substrate for attachment whereas the latter obtains protection against parasitic infections...

..Hence, trout presence may instead reduce parasite burdens in galaxias by either reducing galaxias density or by altering galaxias foraging behaviour...

..Overall, the existence of variability in immune response elicited by different parasite clones is promising for future ecological immunology studies using this system...

..The culture procedures developed here can therefore be used in the future as a system under which to culture marine trematode parthenitae for experimental studies...

..Beyond demonstrating the inevitable convergence of disparate lineages across biological hyperspace towards a limited set of adaptive strategies, this synthesis also provides a unifying framework for the study of parasitism...

..Both these feeding behaviours of birds are known to occur in the field...

..Here, the prospects offered by both approaches, as well as their limitations, are highlighted...

..These findings indicate that particular species characters may be evolutionary drivers of diversity, whose effects could also apply in other taxa...

..Interaction frequency may be a key determinant of specialisation and abundance in host-parasite systems...

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..This opinion article discusses the potential effects of OA on host and parasite species and proposes the use of parasites as bioindicators of OA disturbance...

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..The available data suggest that current estimates of helminth diversity may need to be doubled (tripled for trematodes) to better reflect extant diversity...

..Nematode body size may thus determine the abundance achieved by a species but not how many species can coexist; the limiting similarity between coexisting species must depend on other biological traits...

..liliana. However, due to the low infection intensity and population density of M. liliana, its overall impact as a sink for echinostome populations in the ecosystem is probably negligible...

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..These results demonstrate the existence of genetic variation in host preferences, as well as the effect of environmental variables on observed patterns of host use...

..500 to 0.905, and three to 14 alleles were detected in 24 trematode metacercariae. These loci are currently being used to investigate the molecular ecology of this species within its intermediate hosts...

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..The study of shorter life cycles offers an opportunity to understand the forces shaping the evolution of life cycles in general...

..affinis than within H. filiformis. It remains to be determined whether the polychaete species in which larger sizes are achieved is also the one in which transmission to fish hosts is maximized...

..These results suggest that there is an increasing gap in the quantity and general importance of the research carried out on different helminth taxa...