- Email: [email protected]
Guess who's coming to dinner? Ecologists and parasitologists sit at the same table
Update
TRENDS in Parasitology
based solely on morphological analysis, this in an age when molecular markers are widely available. Reinert et al. also controversially used Bremer support values to justify these changes. Therefore, it is not the name change per se that troubles many people, but the fact that a change has been made to the scientific name of an important human disease organism during an early stage of research into its systematic relationships. Reinert et al. could have introduced a system of species–group designations of neutral nomenclature instead of the 30 new genera because names of species–groups are outside the jurisdiction of the Code. This would have served a useful interim purpose until the generic relationships of the taxa involved are properly worked out using additional techniques of taxonomic characterization and analysis. Because taxonomists have the freedom to change names with relative ease, often names that are established in the public domain, they also have a responsibility that goes beyond their science to those who use the products of their research on a daily basis.
Vol.22 No.1 January 2006
9
Evidently, names might have to change following taxonomic research, even those of medically or otherwise important animals, but these changes must be based on clear evidence, especially when the names affected have far-reaching consequences. Although animal taxonomy is conducted largely in a spirit of responsibility and awareness of the needs of its users, it is imperative that taxonomists understand that their responsibilities extend beyond their immediate professional concerns, into the wider world of science and, ultimately, out into the public realm.
References 1 International Commission on Zoological Nomenclature (1999) International Code of Zoological Nomenclature, 4th edn, International Trust for Zoological Nomenclature 2 Reinert, J.F. et al. (2004) Phylogeny and classification of Aedini (Diptera: Culicidae), based on morphological characters of all life stages. Zool. J. Linn. Soc. 142, 289–368 1471-4922/$ - see front matter Q 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.pt.2005.11.003
Book Reviews
Guess who’s coming to dinner? Ecologists and parasitologists sit at the same table Parasitism & Ecosystems edited by Fre´de´ric Thomas, Franc¸ois Renaud and Jean-Franc¸ois Gue´gan. Oxford University Press, 2005. £34.95 (221 pages) ISBN 0198529872
David J. Marcogliese St Lawrence Centre, Environment Canada, 105 McGill, Montreal, Quebec, Canada, H2Y 2E7
In recent years, a multitude of books, reviews and symposia dedicated to the ecology and ecological impacts of parasitism has appeared. As yet another contribution to this area, Parasitism & Ecosystems explores further the potential consequences of parasitism for ecosystems. The editors have amassed 12 contributions from 26 scientists, including parasitologists (e.g. Gue´gan, Renaud, Sukhdeo and Tinsley), evolutionary ecologists studying host–parasite systems (e.g. Lafferty, Møller, Morand and Poulin), epidemiologists (e.g. Dobson and Read) and ecologists (e.g. Holt, Loreau, Mittelbach and Tilman). Therefore, one might anticipate that this volume would provide a wealth of new insights and different viewpoints. However, the menu is limited. Virtually all of the authors define parasitism in the broadest sense, in line with developments in parasite Corresponding author: Marcogliese, D.J. ([email protected]). Available online 16 November 2005 www.sciencedirect.com
ecology during the past 25 years. The various contributors often employ mathematical models, correlative techniques and comparative phylogenetic analyses to search for patterns and effects. These efforts lead to interesting insights and predictions but, barring the outstanding work by Tinsley, the book seems to lack detailed studies of the biology of the host–parasite interactions in an ecosystem context. Despite great strides being made in ecosystem research using a mesocosm approach, little progress has been made applying this methodology in parasite ecology, excepting recent work on the combined effects of stressors – notably parasites and pesticides – on anuran development. However, this issue goes unmentioned throughout the book. Parasitism & Ecosystems contains some useful reviews of recent developments in ecology, including those by Loreau et al. about ecosystem science, Gue´gan et al. regarding species–area and local–regional patterns, and Sukhdeo and Hernandez concerning parasites and food webs. However, similar ideas and reviews have been published elsewhere by others, and those familiar with current developments in ecosystem research, parasite
Update
10
TRENDS in Parasitology
ecology and epidemiology will not find much meat to chew on here. References to key ecosystem studies are omitted. Notably, the chapter about ecosystems suggests that parasites and disease have stronger impacts at higher trophic levels but, unfortunately, neglects the growing body of work demonstrating that plant parasites affect plant species community structure and dynamics, mediating interactions between plants and other organisms [1]. The importance of viruses for the abundance and species composition of phytoplankton, accounting for up to 25% of the organic carbon cycling in the world’s oceans, is ignored [2,3]. Current ideas developed from an ecosystem approach recur throughout the book. Counterintuitive predictions emerge as a result of cascading and indirect effects of parasitism on the food web (Holt and Boulinier, Hudson, and Lafferty and Kuris). It is well established that parasites and disease, by regulating host populations of keystone species, will affect whole communities and ecosystems. However, the subtle, indirect effects of parasitism, particularly parasite-mediated competition, have ecosystem consequences that might otherwise be unanticipated (Hudson, Møller and Thomas et al.). The role of parasitism in the success or failure of introduced species (Lafferty and Kuris, Møller and Thomas et al.), the importance of scale and spatial distribution for parasite population dynamics (Brown et al., Gue´gan et al., and Holt and Boulinier), the implications of specialist versus generalist parasites for effects on hosts (Brown et al., Hudson, and Sukhdeo and Hernandez) and the
Vol.22 No.1 January 2006
idea that parasites can enhance stability (Holt and Boulinier, Lafferty and Kuris, and Møller) are discussed throughout. Although interesting and contemporary, these avenues are well trodden elsewhere. In an original contribution, Sukhdeo and Hernandez measure the biomass of parasites in a food web and incorporate the results into a trophic pyramid showing that parasites seem to follow the same energetic rules as free-living species. Although Parasitism & Ecosystems will be of only limited use to those already aware of contemporary ideas in parasite ecology, it might prove beneficial for students developing an interest in, and researchers unfamiliar with, current trends in ecological epidemiology and parasitology. By no means does it replace the excellent summary material already available. This book seems to be an acceptable appetizer but it leaves one pining for a gourmet meal. It is clear that, as Mittelbach writes in the conclusion, ecologists and parasitologists speak a different language, and a communication gap exists between them. It is time to bring them together at the table for a real feast. References 1 Pennings, S.C. and Callaway, R.M. (2002) Parasitic plants: parallels and contrasts with herbivores. Oecologia 131, 479–489 2 Suttle, C.A. (2005) Viruses in the sea. Nature 437, 356–361 3 Wilhelm, S.W. and Suttle, C.A. (1999) Viruses and nutrient cycles in the sea. BioScience 49, 781–788 1471-4922/$ - see front matter Crown Copyright Q 2005 Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.pt.2005.10.001
Haematophagy revisited The Biology of Blood-sucking in Insects (2nd edn) by Michael Lehane. Cambridge University Press, 2005. £35.00 pbk (321 pages) ISBN 10 0-521-54395-9
Chris J. Schofield London School of Hygiene and Tropical Medicine, London, UK, WC1 E7HT
Interest in blood-sucking insects stems not only from their epidemiological importance as pests and vectors of disease but also from their evolutionary history and physiological adaptations. To suck vertebrate blood requires a level of pre-adaptation, a means to encounter the host, and a series of evolutionary steps to minimize host disturbance, counter host defensive measures, and digest the ingested fluids. Compounds associated with these adaptations are beginning to show various potential uses, not only for Corresponding author: Schofield, C.J. ([email protected]). Available online 28 November 2005 www.sciencedirect.com
finding new ways to control the pest species but also as new pharmacological components such as anticoagulants, anaesthetics, analgaesics, vasodilators and vasoconstrictors. This admirable book covers all these stages, clearly presented and logically arranged through evolutionary theory, host choice and orientation, probing, antihaemostasis, digestion and bloodmeal utilization. Lehane has specialized in these aspects, with an impressive publication record on digestive physiology – especially of Stomoxys but also tsetse, Triatominae, mosquitoes, and some of the lesser-known plagues of the veterinary world. This extensive experience is well reflected in the book, with particular strengths being the physiological aspects of ingestion, digestion, and insect defence
TRENDS in Parasitology
based solely on morphological analysis, this in an age when molecular markers are widely available. Reinert et al. also controversially used Bremer support values to justify these changes. Therefore, it is not the name change per se that troubles many people, but the fact that a change has been made to the scientific name of an important human disease organism during an early stage of research into its systematic relationships. Reinert et al. could have introduced a system of species–group designations of neutral nomenclature instead of the 30 new genera because names of species–groups are outside the jurisdiction of the Code. This would have served a useful interim purpose until the generic relationships of the taxa involved are properly worked out using additional techniques of taxonomic characterization and analysis. Because taxonomists have the freedom to change names with relative ease, often names that are established in the public domain, they also have a responsibility that goes beyond their science to those who use the products of their research on a daily basis.
Vol.22 No.1 January 2006
9
Evidently, names might have to change following taxonomic research, even those of medically or otherwise important animals, but these changes must be based on clear evidence, especially when the names affected have far-reaching consequences. Although animal taxonomy is conducted largely in a spirit of responsibility and awareness of the needs of its users, it is imperative that taxonomists understand that their responsibilities extend beyond their immediate professional concerns, into the wider world of science and, ultimately, out into the public realm.
References 1 International Commission on Zoological Nomenclature (1999) International Code of Zoological Nomenclature, 4th edn, International Trust for Zoological Nomenclature 2 Reinert, J.F. et al. (2004) Phylogeny and classification of Aedini (Diptera: Culicidae), based on morphological characters of all life stages. Zool. J. Linn. Soc. 142, 289–368 1471-4922/$ - see front matter Q 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.pt.2005.11.003
Book Reviews
Guess who’s coming to dinner? Ecologists and parasitologists sit at the same table Parasitism & Ecosystems edited by Fre´de´ric Thomas, Franc¸ois Renaud and Jean-Franc¸ois Gue´gan. Oxford University Press, 2005. £34.95 (221 pages) ISBN 0198529872
David J. Marcogliese St Lawrence Centre, Environment Canada, 105 McGill, Montreal, Quebec, Canada, H2Y 2E7
In recent years, a multitude of books, reviews and symposia dedicated to the ecology and ecological impacts of parasitism has appeared. As yet another contribution to this area, Parasitism & Ecosystems explores further the potential consequences of parasitism for ecosystems. The editors have amassed 12 contributions from 26 scientists, including parasitologists (e.g. Gue´gan, Renaud, Sukhdeo and Tinsley), evolutionary ecologists studying host–parasite systems (e.g. Lafferty, Møller, Morand and Poulin), epidemiologists (e.g. Dobson and Read) and ecologists (e.g. Holt, Loreau, Mittelbach and Tilman). Therefore, one might anticipate that this volume would provide a wealth of new insights and different viewpoints. However, the menu is limited. Virtually all of the authors define parasitism in the broadest sense, in line with developments in parasite Corresponding author: Marcogliese, D.J. ([email protected]). Available online 16 November 2005 www.sciencedirect.com
ecology during the past 25 years. The various contributors often employ mathematical models, correlative techniques and comparative phylogenetic analyses to search for patterns and effects. These efforts lead to interesting insights and predictions but, barring the outstanding work by Tinsley, the book seems to lack detailed studies of the biology of the host–parasite interactions in an ecosystem context. Despite great strides being made in ecosystem research using a mesocosm approach, little progress has been made applying this methodology in parasite ecology, excepting recent work on the combined effects of stressors – notably parasites and pesticides – on anuran development. However, this issue goes unmentioned throughout the book. Parasitism & Ecosystems contains some useful reviews of recent developments in ecology, including those by Loreau et al. about ecosystem science, Gue´gan et al. regarding species–area and local–regional patterns, and Sukhdeo and Hernandez concerning parasites and food webs. However, similar ideas and reviews have been published elsewhere by others, and those familiar with current developments in ecosystem research, parasite
Update
10
TRENDS in Parasitology
ecology and epidemiology will not find much meat to chew on here. References to key ecosystem studies are omitted. Notably, the chapter about ecosystems suggests that parasites and disease have stronger impacts at higher trophic levels but, unfortunately, neglects the growing body of work demonstrating that plant parasites affect plant species community structure and dynamics, mediating interactions between plants and other organisms [1]. The importance of viruses for the abundance and species composition of phytoplankton, accounting for up to 25% of the organic carbon cycling in the world’s oceans, is ignored [2,3]. Current ideas developed from an ecosystem approach recur throughout the book. Counterintuitive predictions emerge as a result of cascading and indirect effects of parasitism on the food web (Holt and Boulinier, Hudson, and Lafferty and Kuris). It is well established that parasites and disease, by regulating host populations of keystone species, will affect whole communities and ecosystems. However, the subtle, indirect effects of parasitism, particularly parasite-mediated competition, have ecosystem consequences that might otherwise be unanticipated (Hudson, Møller and Thomas et al.). The role of parasitism in the success or failure of introduced species (Lafferty and Kuris, Møller and Thomas et al.), the importance of scale and spatial distribution for parasite population dynamics (Brown et al., Gue´gan et al., and Holt and Boulinier), the implications of specialist versus generalist parasites for effects on hosts (Brown et al., Hudson, and Sukhdeo and Hernandez) and the
Vol.22 No.1 January 2006
idea that parasites can enhance stability (Holt and Boulinier, Lafferty and Kuris, and Møller) are discussed throughout. Although interesting and contemporary, these avenues are well trodden elsewhere. In an original contribution, Sukhdeo and Hernandez measure the biomass of parasites in a food web and incorporate the results into a trophic pyramid showing that parasites seem to follow the same energetic rules as free-living species. Although Parasitism & Ecosystems will be of only limited use to those already aware of contemporary ideas in parasite ecology, it might prove beneficial for students developing an interest in, and researchers unfamiliar with, current trends in ecological epidemiology and parasitology. By no means does it replace the excellent summary material already available. This book seems to be an acceptable appetizer but it leaves one pining for a gourmet meal. It is clear that, as Mittelbach writes in the conclusion, ecologists and parasitologists speak a different language, and a communication gap exists between them. It is time to bring them together at the table for a real feast. References 1 Pennings, S.C. and Callaway, R.M. (2002) Parasitic plants: parallels and contrasts with herbivores. Oecologia 131, 479–489 2 Suttle, C.A. (2005) Viruses in the sea. Nature 437, 356–361 3 Wilhelm, S.W. and Suttle, C.A. (1999) Viruses and nutrient cycles in the sea. BioScience 49, 781–788 1471-4922/$ - see front matter Crown Copyright Q 2005 Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.pt.2005.10.001
Haematophagy revisited The Biology of Blood-sucking in Insects (2nd edn) by Michael Lehane. Cambridge University Press, 2005. £35.00 pbk (321 pages) ISBN 10 0-521-54395-9
Chris J. Schofield London School of Hygiene and Tropical Medicine, London, UK, WC1 E7HT
Interest in blood-sucking insects stems not only from their epidemiological importance as pests and vectors of disease but also from their evolutionary history and physiological adaptations. To suck vertebrate blood requires a level of pre-adaptation, a means to encounter the host, and a series of evolutionary steps to minimize host disturbance, counter host defensive measures, and digest the ingested fluids. Compounds associated with these adaptations are beginning to show various potential uses, not only for Corresponding author: Schofield, C.J. ([email protected]). Available online 28 November 2005 www.sciencedirect.com
finding new ways to control the pest species but also as new pharmacological components such as anticoagulants, anaesthetics, analgaesics, vasodilators and vasoconstrictors. This admirable book covers all these stages, clearly presented and logically arranged through evolutionary theory, host choice and orientation, probing, antihaemostasis, digestion and bloodmeal utilization. Lehane has specialized in these aspects, with an impressive publication record on digestive physiology – especially of Stomoxys but also tsetse, Triatominae, mosquitoes, and some of the lesser-known plagues of the veterinary world. This extensive experience is well reflected in the book, with particular strengths being the physiological aspects of ingestion, digestion, and insect defence