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The times they are a-changin’: evolution and revolution in animal ecology publishing Kenneth Wilson*, Tim Coulson, Mike Boots, Liz Baker and Peter Livermore Lancaster Environment Centre, Lancaster University, Lancaster, UK; Department of Zoology, University of Oxford, Oxford, UK; College of Life and Environmental Sciences, University of Exeter, Cornwall Campus, Exeter, UK; and British Ecological Society, London, UK

Summary 1 The persistence of parasites that are only seen in intermittent outbreaks has intrigued ecologists. Long the subject of speculation, there is now evidence that viral insect diseases can cause covert as well as overt infections. 2 Typically, infection leads to overtly diseased individuals that are infectious and die as a result of the disease, but it can also produce other individuals that show a covert, non-infectious pathology, which is typically asymptomatic. Covertly infected individuals do not die as a result of infection, although they may be affected sublethally such that their reproductive output falls, they may transmit the covert infection vertically and, crucially, they may convert at some rate to overt infectious individuals. In this way the parasites are able to persist in host populations and can be detected only by the use of molecular techniques. 3 Here, we apply novel analytical techniques to a general host–parasite modelling framework and examine the population dynamical consequences of such covert infections. 4 The interplay between various stabilizing and destabilizing forces leads to a highly complex pattern of host dynamics, including a theoretically intriguing pinch point. Covert infections may be stabilizing or destabilizing depending on the specific characteristics of the interaction, particularly in relation to the rate of conversion from covert to overt infection. 5 In general terms, intermediate rates of conversion are stabilizing, while high and low rates may each destabilize the host population. In contrast, there is no consistent pattern for the role of vertical transmission because, in some cases, high levels are stabilizing while in others they are destabilizing. 6 Thus, our results demonstrate that relatively subtle pathogen effects such as covert infections can have important and novel dynamical impacts on the host–pathogen interaction. It also suggests that the effects of covert infection are likely to be system-specific and information may be required on a system-by-system basis in order to make predictions.

Summary 1. Since parasite transmission is often density-dependent, group living is normally thought to lead to an increased exposure to parasitism. As a consequence, it is predicted that animals living in groups will invest more resources (energy, time, risk, etc.) in parasite defence than those living solitarily. 2. We tested this prediction by measuring basal immune parameters in the larvae of 12 species of Lepidoptera, grouped into six phylogenetically matched species-pairs, each comprising one solitary feeding and one gregariously feeding species. 3. Contrary to expectation, the solitary species in all six species-pairs had higher total haemocyte counts than the gregarious species, and in five out of six species-pairs the solitary species also exhibited higher phenoloxidase activity. Both measurements were positively correlated with each other and with the magnitude of the cellular encapsulation response. 4. The relationship between infection risk and group living was investigated with a dynamic, spatially explicit, host‐pathogen model. This shows that when individuals aggregate in groups, the per capita risk of infection can be reduced if the lower betweengroup transmission more than compensates for the higher within-group transmission. 5. We conclude that the expectation that group living always leads to increased exposure to pathogens and parasites is overly simplistic, and that the specific details of the social system in question will determine if there is increased or decreased exposure

Summary 1. A large group of parasites, including many of the larval pathogens of insects, cause an infection from which infectious hosts are unable to recover. In addition, a proportion of those individuals that do not develop the lethal disease on exposure to the parasite may still be harmed by it. 2. We examined the role of these sublethal effects on host-population dynamics. Specifically we considered the case where there are three distinct classes of individuals: (i) susceptibles; (ii) infected and infectious individuals that will not reproduce and cannot recover; and (iii) sublethally infected individuals. 3. Parasites with sublethal effects are less likely to persist and control their host population. This is a consequence of the sublethally infected individuals not being infective. Less intuitively, the sublethal infection is highly destabilizing, increasing the risk of cyclic behaviour in host–parasite population densities. 4. Because sublethal infection acts as a destabilizing force in these host–parasite interactions, parasites with pronounced sublethal effects may be less effective as classical biological control agents.

In a world where impact factors and journal rankings are pored over by prospective authors and publishers alike, 2012 was an excellent year for the Journal of Animal Ecology as our impact factor rose to 4937. However, maximizing a journal’s impact factor should not be the only focus of editors. The primary role of the Journal of Animal Ecology is to publish papers that animal ecologists will find novel and thought-provoking and which advance the broader field of animal ecology. Over the last 81 years, the journal has published some of the most influential research in animal ecology, and we remain dedicated to publishing papers that challenge current ideas and shape the field. This is certainly evident in the articles we have published over the last year; whether it has been unravelling the ecology of wildlife diseases, tracing the movements and mapping space use of animals or disentangling the myriad interactions that shape animal communities and ecosystems, topical, cutting-edge research has occupied space in every issue. This coming year will be no exception, and we hope to continue receiving such high-quality work. As ever, the journal’s focus and emphasis is on work using data and analyses to quantitatively test theory or to develop new ideas. Reports of advances in both the way data are collected and the way they are analysed continue to provide exciting research avenues for the future that we wish to include in the pages of this publication. And that is true for all areas of animal ecology research; we welcome submissions ranging from molecular to macroecological studies. This range is reflected in the breadth of expertise on our Editorial Board. Our Associate Editors, along with the many kind reviewers who freely gave their time to assess the manuscripts submitted to the journal, did a fantastic job in making 2012 the success it was. We look forward to another prosperous year ahead. During 2012, we saw various personnel changes within the journal’s editorial office. Jenny Guthrie, our Managing Editor for 10 years, left the employ of the British Ecological Society following a restructure of the Society’s publications team. Jenny played a critical role in developing the journal over the last decade, and much of its current success is due to her eye for detail and hard work. The restructure has seen the appointment of Peter Livermore as the journal’s Assistant Editor and Liz Baker take over as