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TRENDS in Ecology & Evolution Vol.17 No.4 April 2002
197
Book Review
Marine fisheries: a broad view of an expanding field Marine Fisheries Ecology S. Jennings, M.J. Kaiser and J.D. Reynolds. Blackwell Science, 2001. £29.50 pbk (xiii + 417 pages) ISBN 0 632 05098 5
In response to global concern for recent declines in marine fisheries, there has been a surge of interest in identifying and remedying the root cause(s) [1,2]. Marine fisheries management has shifted from a focus on maximum sustained yield (MSY) of single species to a greater emphasis on sustaining populations in a broader context, which considers the effects of fishing on habitat and the whole ecosystem, including paying attention to the effects of the varying ocean environment over annual to decadal scales. Increasing awareness of problems in marine conservation has attracted the attention of mainstream ecologists, and several conservation organizations. Marine Fisheries Ecology is a broad exposition of the background for marine fisheries, covering the biological and physical bases of biological production, population dynamics, stock assessment, resource economics, ecosystem effects and aquaculture. As the authors note, each topic is covered briefly, at an introductory level. There is growing consensus that improvement in fishery management will require changes in institutions and methods to address the combination of (a) incessant pressure for policies leading to immediate, short-term economic gain; and (b) the uncertainty that impedes accurate prediction of the consequences of those policies [1–3]. The effect of these two factors on management is a unidirectional increase in harvest rates through a mechanism known as the ‘ratchet effect’. Management bodies weigh the certainty of lost jobs and near-term profits against the uncertain projections of a potential for population collapse, and chose the politically more appealing course. Promising new approaches address this phenomenon, not only through direct reduction of uncertainty (e.g. through process research, monitoring effects of global change and meta-analysis of taxonomic similarity for parameter estimates) and reduction of socio-economic
pressure for increasing harvests (e.g. through co-management, fishing rights and eco-certification), but also by development of decision methods and institutions that are robust to uncertainty (e.g. marine reserves, adaptive management, decision analysis and the precautionary approach). For example, the precautionary approach [4,5] implies that, instead of simply continuing to aim for a target, such as MSY, as a fishery continues to decline, managers set predetermined limits on some observable measure of population persistence (i.e. limit reference points) and agree that, if the population falls below that limit, agreed-upon measures will be taken to curtail fishing with no further debate. The presentation of topics in the book is expository, rather than comprehensive and critical. For example, the material on population dynamics and stock assessment is brief, with few examples. There is no detailed description of new emphases on population persistence and the dynamic function of reference points. The authors note that if the reader really wants to do a stock assessment, they should consult one of the references given. As another example, new approaches to ecosystem modeling are initially presented enthusiastically in Chapter 8 without caveats (cf. [2,6]), waiting until the final chapter to note that our limited understanding of species interactions ultimately constrains use of such models for management prediction. The authors have drawn on their experience in fisheries throughout the 1990s to provide an introduction to a broad range of topics in this expanding field. This book is suitable for a survey course for ecologists and those from other disciplines interested in fishery issues. However, it cannot be expected to provide comprehensive training for fishery ecologists. That would require full courses in several of the topics touched upon in the book (e.g. resource economics, stock assessment, and biological and physical oceanography). Louis W. Botsford Dept of Wildlife, Fish and Conservation Biology, University of California, Davis, CA 95616, USA. e-mail: [email protected] References 1 Ludwig, D. et al. (1993) Uncertainty, resource exploitation and conservation: lessons from history. Science 260, 17,36
2 Botsford, L.W. et al. (1997) The management of fisheries and marine ecosystems. Science 277, 509–515 3 Botsford, L.W. and Parma, A.M. Uncertainty in marine management. In Marine Conservation Biology (Norse, E. and Crowder, L.B., eds), Island Press (in press) 4 FAO (1996) Precautionary Approach to Capture Fisheries and Species Introductions. Elaborated by the Technical Consultation on the Precautionary Approach to Capture Fisheries (including Species Introductions). Lysekil, Sweden, 6–13 June 1995, FAO 5 Caddy, J.F. and Mahon, R. (1995) Reference points for fisheries management. FAO Fish. Tech. Pap.347 6 Walters, C.J. et al. (1997) Structuring dynamic models of exploited ecosystems from trophic massbalance assessments. Rev. Fish Biol. Fish. 6, 125–137
Magnificent mammals The New Encyclopedia of Mammals edited by David Macdonald. Oxford University Press, 2001. £35.00 hbk (xxxi + 930 pages) ISBN 0 19 850823 9
This is a revision of the 1984 Encyclopedia of Mammals, which was also edited by David Macdonald, but this time there is also an assistant editor and eight advisory editors. A work that attempts to deal with every living mammal species (~4600) is daunting. Even before starting, the task of deciding what classification system to use, and how to present it, has to be tackled, which is particularly difficult given that molecular biology is rapidly challenging many of the classic ideas about systematics and mammalian evolution. Inevitably, some arbitrary decisions had to be made on layout and order that might not please everybody. However, there is a diagram and table at the beginning of the book that I found very useful for navigating through the lay out and quickly finding the group that I was interested in. Where applicable, brief descriptions of the various viewpoints regarding the classification and evolution of the group, and the reason for placing it where it is in the book, are given. There is a dazzling amount of information available in this volume. A feature is that almost everything that is written is done so by nearly 300 contributors with first-hand knowledge of at least the family and, in many cases, the species, being written about. After an extended and fascinating introductory essay on mammals, the taxon accounts are presented. For each order, or, in some cases, group of orders, there is a general introduction highlighting their common and/or special
http://tree.trends.com 0169-5347/02/$ – see front matter © 2002 Elsevier Science Ltd. All rights reserved.
198
Forum
features. The main body contains natural history accounts of species, groups of species or families, depending on the detail of information available, and a factfile summarizing the classification, distribution, habitat, size, coat, diet, breeding, longevity and conservation status of the taxon. Liberally scattered throughout are ‘Special Features’boxes, detailing new discoveries or interesting aspects and issues. Finally, all taxon accounts are illustrated by what must rank as one of the most interesting and stunning selection of mammal photographs in a single book, aided and abetted by hundreds of beautifully detailed and accurate paintings and line drawings. The book is completed by a species list of certain mammalian orders, (it is unclear what the criteria for inclusion were), an extended glossary (always useful in a book of this nature) and a comprehensive bibliography. It was impossible to read the whole book, so inevitably I focussed on the species that I know most about. By and large, I was very impressed by the up-to-date coverage and accuracy of the information. However, in the introduction to the wild dog section, it states that females migrate into the pack, whereas males stay with the natal group – an error from the first edition that has not been corrected. However, in the actual species account, it does state that both sexes emigrate from their natal packs. It also states in the factfile for the same species that gestation is 70–73 days, yet states in the text that a litter of pups is born within a month of a pack forming! These are trivial errors inevitable in a book of this size. I hope that those reading the book and finding such errors will inform the editor for correction in future editions. On the whole, this is a magnificent work that will thrill and educate anyone interested in natural history from professional microbiologists and computer modelers, through active field biologists, to armchair philosophers and amateur National Geographic and Discovery TV couch potatoes. It will seriously improve the standard of any school project on mammals and, most importantly, contribute to the conservation of these exciting and vital animals through education and awareness. Gus Mills South African National Parks, Endangered Wildlife Trust and Dept of Zoology, University of Pretoria, Private Bag X402, Skukuza, 1350, South Africa. e-mail: [email protected]
TRENDS in Ecology & Evolution Vol.17 No.4 April 2002
Epigenetics again Animal Traditions: Behavioral Inheritance in Evolution by Eytan Avital and Eva Jablonka. Cambridge University Press, 2000. £50.00 hbk (xiii + 432 pages) ISBN 0 521 66273 7
My first encounter with E.O Wilson’s Sociobiology [1] was an absolutely enticing experience. I was charmed and intrigued by the ideas, examples and illustrations. What I would not have anticipated with pleasure was the endurance of the controversy over the significance of genetic and environmental contributions to the expression of social behavior that was the response to Wilson’s and other publications espousing, to varying degrees, the genetic regulation of social behavior. Animal Traditions: Behavioral Inheritance in Evolution is a continuation of the ‘epigenetic’ element of the controversy. Proponents of the epigenetic approach argue that emergent properties of social behavior exist that are far more than the sum of the genetic influences on behavioral traits, and that this requires that the evolution of social behavior is viewed differently from the evolution of other kinds of traits. Although the passing of cultural characteristics between generations undoubtedly requires that we accept transmission of learned behavioral patterns, I have yet to understand why cultural evolution requires a fundamentally different view of evolution than is usually offered. I was hoping that this volume would help explain the distinction to me. Unfortunately, I did not find much new, and I certainly was left unconvinced that we need to think about evolution in new ways when learning is involved in transmission of phenotypes between generations. Examples were familiar without novel interpretation, or they were imaginary, designed to illustrate a point. Little attempt was made to establish generality of the ideas presented, and citations were limited relative to the extent of discussion in the literature. The last two concerns were problematic for me as a research scientist in the field, but are likely to prove less so for those interested simply in understanding the basic arguments. Indeed, the authors note in the preface that they are not attempting a thorough review, but are instead hoping to present an interesting and accessible
discussion of the interplay between genes, learning and behavior for those unfamiliar with the arguments. For such readers, the volume might prove a very rewarding read, with the elements I found problematic being an advantage instead. I very much enjoyed the historical approach taken in the chapter ‘Darwin meets Lamarck’. Too often the historical development of ideas is ignored in modern literature. Discussion of the Baldwin effect [2], of Waddington’s [3] ideas concerning genetic assimilation, and of Immelman’s [4] seminal discussion of the potential role of imprinting in speciation is rarely encountered in the behavioral literature or in the literature on speciation. All three processes might well have played a role in the evolutionary divergence of taxa, and in speciation – a point made very nicely by these authors. I found the discussion of Darwin as a Lamarkian much less compelling, because neither Darwin nor Lamarck had access to our knowledge of the genetic bases of behavior. I find it hard to believe that either would have failed to embrace modern genetics had they the opportunity to do so, and thus find the argument that Darwin and Lamark held Lamarkian views to be rather uncompelling logical support for modern epigenetic approaches to the study of behavior. In summary, as a behavioral biologist, I found little in the way of novel insight in this book, and found the long descriptions of process through example slow going. However, the book could prove to be a wonderful read for those interested in an introduction to cultural inheritance and its potential role in evolution. The authors have clearly thought a lot about the issues, and describe them articulately for lay readers interested in animal behavior. Susan A. Foster Dept of Biology, Clark University, 950 Main Street, Worcester, MA 01610-1477, USA. e-mail: [email protected] References 1 Wilson, E.O. (1975) Sociobiology, Harvard University Press 2 Morgan, C.L. (1900) Animal Behaviour, Edward Arnold 3 Waddington, C.H. (1957) The Strategy of the Genes, Allen and Unwin 4 Immelmann, K. (1975) The evolutionary significance of early experience. In Function and Evolution in Behaviour: Essays in Honour of Professor Niko Tinbergen (Baerends, G. et al., eds), pp. 243–253, Clarendon
http://tree.trends.com 0169-5347/02/$ – see front matter © 2002 Elsevier Science Ltd. All rights reserved.
TRENDS in Ecology & Evolution Vol.17 No.4 April 2002
197
Book Review
Marine fisheries: a broad view of an expanding field Marine Fisheries Ecology S. Jennings, M.J. Kaiser and J.D. Reynolds. Blackwell Science, 2001. £29.50 pbk (xiii + 417 pages) ISBN 0 632 05098 5
In response to global concern for recent declines in marine fisheries, there has been a surge of interest in identifying and remedying the root cause(s) [1,2]. Marine fisheries management has shifted from a focus on maximum sustained yield (MSY) of single species to a greater emphasis on sustaining populations in a broader context, which considers the effects of fishing on habitat and the whole ecosystem, including paying attention to the effects of the varying ocean environment over annual to decadal scales. Increasing awareness of problems in marine conservation has attracted the attention of mainstream ecologists, and several conservation organizations. Marine Fisheries Ecology is a broad exposition of the background for marine fisheries, covering the biological and physical bases of biological production, population dynamics, stock assessment, resource economics, ecosystem effects and aquaculture. As the authors note, each topic is covered briefly, at an introductory level. There is growing consensus that improvement in fishery management will require changes in institutions and methods to address the combination of (a) incessant pressure for policies leading to immediate, short-term economic gain; and (b) the uncertainty that impedes accurate prediction of the consequences of those policies [1–3]. The effect of these two factors on management is a unidirectional increase in harvest rates through a mechanism known as the ‘ratchet effect’. Management bodies weigh the certainty of lost jobs and near-term profits against the uncertain projections of a potential for population collapse, and chose the politically more appealing course. Promising new approaches address this phenomenon, not only through direct reduction of uncertainty (e.g. through process research, monitoring effects of global change and meta-analysis of taxonomic similarity for parameter estimates) and reduction of socio-economic
pressure for increasing harvests (e.g. through co-management, fishing rights and eco-certification), but also by development of decision methods and institutions that are robust to uncertainty (e.g. marine reserves, adaptive management, decision analysis and the precautionary approach). For example, the precautionary approach [4,5] implies that, instead of simply continuing to aim for a target, such as MSY, as a fishery continues to decline, managers set predetermined limits on some observable measure of population persistence (i.e. limit reference points) and agree that, if the population falls below that limit, agreed-upon measures will be taken to curtail fishing with no further debate. The presentation of topics in the book is expository, rather than comprehensive and critical. For example, the material on population dynamics and stock assessment is brief, with few examples. There is no detailed description of new emphases on population persistence and the dynamic function of reference points. The authors note that if the reader really wants to do a stock assessment, they should consult one of the references given. As another example, new approaches to ecosystem modeling are initially presented enthusiastically in Chapter 8 without caveats (cf. [2,6]), waiting until the final chapter to note that our limited understanding of species interactions ultimately constrains use of such models for management prediction. The authors have drawn on their experience in fisheries throughout the 1990s to provide an introduction to a broad range of topics in this expanding field. This book is suitable for a survey course for ecologists and those from other disciplines interested in fishery issues. However, it cannot be expected to provide comprehensive training for fishery ecologists. That would require full courses in several of the topics touched upon in the book (e.g. resource economics, stock assessment, and biological and physical oceanography). Louis W. Botsford Dept of Wildlife, Fish and Conservation Biology, University of California, Davis, CA 95616, USA. e-mail: [email protected] References 1 Ludwig, D. et al. (1993) Uncertainty, resource exploitation and conservation: lessons from history. Science 260, 17,36
2 Botsford, L.W. et al. (1997) The management of fisheries and marine ecosystems. Science 277, 509–515 3 Botsford, L.W. and Parma, A.M. Uncertainty in marine management. In Marine Conservation Biology (Norse, E. and Crowder, L.B., eds), Island Press (in press) 4 FAO (1996) Precautionary Approach to Capture Fisheries and Species Introductions. Elaborated by the Technical Consultation on the Precautionary Approach to Capture Fisheries (including Species Introductions). Lysekil, Sweden, 6–13 June 1995, FAO 5 Caddy, J.F. and Mahon, R. (1995) Reference points for fisheries management. FAO Fish. Tech. Pap.347 6 Walters, C.J. et al. (1997) Structuring dynamic models of exploited ecosystems from trophic massbalance assessments. Rev. Fish Biol. Fish. 6, 125–137
Magnificent mammals The New Encyclopedia of Mammals edited by David Macdonald. Oxford University Press, 2001. £35.00 hbk (xxxi + 930 pages) ISBN 0 19 850823 9
This is a revision of the 1984 Encyclopedia of Mammals, which was also edited by David Macdonald, but this time there is also an assistant editor and eight advisory editors. A work that attempts to deal with every living mammal species (~4600) is daunting. Even before starting, the task of deciding what classification system to use, and how to present it, has to be tackled, which is particularly difficult given that molecular biology is rapidly challenging many of the classic ideas about systematics and mammalian evolution. Inevitably, some arbitrary decisions had to be made on layout and order that might not please everybody. However, there is a diagram and table at the beginning of the book that I found very useful for navigating through the lay out and quickly finding the group that I was interested in. Where applicable, brief descriptions of the various viewpoints regarding the classification and evolution of the group, and the reason for placing it where it is in the book, are given. There is a dazzling amount of information available in this volume. A feature is that almost everything that is written is done so by nearly 300 contributors with first-hand knowledge of at least the family and, in many cases, the species, being written about. After an extended and fascinating introductory essay on mammals, the taxon accounts are presented. For each order, or, in some cases, group of orders, there is a general introduction highlighting their common and/or special
http://tree.trends.com 0169-5347/02/$ – see front matter © 2002 Elsevier Science Ltd. All rights reserved.
198
Forum
features. The main body contains natural history accounts of species, groups of species or families, depending on the detail of information available, and a factfile summarizing the classification, distribution, habitat, size, coat, diet, breeding, longevity and conservation status of the taxon. Liberally scattered throughout are ‘Special Features’boxes, detailing new discoveries or interesting aspects and issues. Finally, all taxon accounts are illustrated by what must rank as one of the most interesting and stunning selection of mammal photographs in a single book, aided and abetted by hundreds of beautifully detailed and accurate paintings and line drawings. The book is completed by a species list of certain mammalian orders, (it is unclear what the criteria for inclusion were), an extended glossary (always useful in a book of this nature) and a comprehensive bibliography. It was impossible to read the whole book, so inevitably I focussed on the species that I know most about. By and large, I was very impressed by the up-to-date coverage and accuracy of the information. However, in the introduction to the wild dog section, it states that females migrate into the pack, whereas males stay with the natal group – an error from the first edition that has not been corrected. However, in the actual species account, it does state that both sexes emigrate from their natal packs. It also states in the factfile for the same species that gestation is 70–73 days, yet states in the text that a litter of pups is born within a month of a pack forming! These are trivial errors inevitable in a book of this size. I hope that those reading the book and finding such errors will inform the editor for correction in future editions. On the whole, this is a magnificent work that will thrill and educate anyone interested in natural history from professional microbiologists and computer modelers, through active field biologists, to armchair philosophers and amateur National Geographic and Discovery TV couch potatoes. It will seriously improve the standard of any school project on mammals and, most importantly, contribute to the conservation of these exciting and vital animals through education and awareness. Gus Mills South African National Parks, Endangered Wildlife Trust and Dept of Zoology, University of Pretoria, Private Bag X402, Skukuza, 1350, South Africa. e-mail: [email protected]
TRENDS in Ecology & Evolution Vol.17 No.4 April 2002
Epigenetics again Animal Traditions: Behavioral Inheritance in Evolution by Eytan Avital and Eva Jablonka. Cambridge University Press, 2000. £50.00 hbk (xiii + 432 pages) ISBN 0 521 66273 7
My first encounter with E.O Wilson’s Sociobiology [1] was an absolutely enticing experience. I was charmed and intrigued by the ideas, examples and illustrations. What I would not have anticipated with pleasure was the endurance of the controversy over the significance of genetic and environmental contributions to the expression of social behavior that was the response to Wilson’s and other publications espousing, to varying degrees, the genetic regulation of social behavior. Animal Traditions: Behavioral Inheritance in Evolution is a continuation of the ‘epigenetic’ element of the controversy. Proponents of the epigenetic approach argue that emergent properties of social behavior exist that are far more than the sum of the genetic influences on behavioral traits, and that this requires that the evolution of social behavior is viewed differently from the evolution of other kinds of traits. Although the passing of cultural characteristics between generations undoubtedly requires that we accept transmission of learned behavioral patterns, I have yet to understand why cultural evolution requires a fundamentally different view of evolution than is usually offered. I was hoping that this volume would help explain the distinction to me. Unfortunately, I did not find much new, and I certainly was left unconvinced that we need to think about evolution in new ways when learning is involved in transmission of phenotypes between generations. Examples were familiar without novel interpretation, or they were imaginary, designed to illustrate a point. Little attempt was made to establish generality of the ideas presented, and citations were limited relative to the extent of discussion in the literature. The last two concerns were problematic for me as a research scientist in the field, but are likely to prove less so for those interested simply in understanding the basic arguments. Indeed, the authors note in the preface that they are not attempting a thorough review, but are instead hoping to present an interesting and accessible
discussion of the interplay between genes, learning and behavior for those unfamiliar with the arguments. For such readers, the volume might prove a very rewarding read, with the elements I found problematic being an advantage instead. I very much enjoyed the historical approach taken in the chapter ‘Darwin meets Lamarck’. Too often the historical development of ideas is ignored in modern literature. Discussion of the Baldwin effect [2], of Waddington’s [3] ideas concerning genetic assimilation, and of Immelman’s [4] seminal discussion of the potential role of imprinting in speciation is rarely encountered in the behavioral literature or in the literature on speciation. All three processes might well have played a role in the evolutionary divergence of taxa, and in speciation – a point made very nicely by these authors. I found the discussion of Darwin as a Lamarkian much less compelling, because neither Darwin nor Lamarck had access to our knowledge of the genetic bases of behavior. I find it hard to believe that either would have failed to embrace modern genetics had they the opportunity to do so, and thus find the argument that Darwin and Lamark held Lamarkian views to be rather uncompelling logical support for modern epigenetic approaches to the study of behavior. In summary, as a behavioral biologist, I found little in the way of novel insight in this book, and found the long descriptions of process through example slow going. However, the book could prove to be a wonderful read for those interested in an introduction to cultural inheritance and its potential role in evolution. The authors have clearly thought a lot about the issues, and describe them articulately for lay readers interested in animal behavior. Susan A. Foster Dept of Biology, Clark University, 950 Main Street, Worcester, MA 01610-1477, USA. e-mail: [email protected] References 1 Wilson, E.O. (1975) Sociobiology, Harvard University Press 2 Morgan, C.L. (1900) Animal Behaviour, Edward Arnold 3 Waddington, C.H. (1957) The Strategy of the Genes, Allen and Unwin 4 Immelmann, K. (1975) The evolutionary significance of early experience. In Function and Evolution in Behaviour: Essays in Honour of Professor Niko Tinbergen (Baerends, G. et al., eds), pp. 243–253, Clarendon
http://tree.trends.com 0169-5347/02/$ – see front matter © 2002 Elsevier Science Ltd. All rights reserved.