Trends in Ecology & Evolution

Published by Elsevier
Online ISSN: 0169-5347
Publications
Article
One of the main tasks confronting community ecologists is to explain why a particular site harbours a certain number of species. The site might range from a drop of water to the whole Earth, and the species might be drawn from a very restricted taxon or include all living organisms. The common problem, however, is to understand the relative importance of speciation and extinction and, more locally, of immigration and loss. Speciation is the ultimate motor driving biodiversity and ecologists need to know the factors influencing rates of speciation, and whether there is a feedback, positive or negative, between species numbers and the generation of new taxa. However, the relative importance of speciation and other factors determining species numbers varies crucially across different scales of enquiry. Here, we explore some of these issues as we move from a macro- to microscale perspective, focusing on a limited number of studies that we believe make important advances in the field.
 
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Points to flaws in review by Judson (1994; TREE 9:9-14).
 
Article
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Article
Recently, researchers in several areas of ecology and evolution have begun to change the way in which they analyze data and make biological inferences. Rather than the traditional null hypothesis testing approach, they have adopted an approach called model selection, in which several competing hypotheses are simultaneously confronted with data. Model selection can be used to identify a single best model, thus lending support to one particular hypothesis, or it can be used to make inferences based on weighted support from a complete set of competing models. Model selection is widely accepted and well developed in certain fields, most notably in molecular systematics and mark-recapture analysis. However, it is now gaining support in several other areas, from molecular evolution to landscape ecology. Here, we outline the steps of model selection and highlight several ways that it is now being implemented. By adopting this approach, researchers in ecology and evolution will find a valuable alternative to traditional null hypothesis testing, especially when more than one hypothesis is plausible.
 
Article
In species with separate sexes, sex determination often has a genetic basis, and in a wide diversity of taxa a pair of cytologically distinguishable 'sex chromosomes' are found such that the chromosome complements of males and females differ (males are often XY and females XX, but sometimes females are ZW whereas males are ZZ). Recent evidence from sequences of sex-linked genes confirms classical genetic evidence that these chromosomes are a homologous pair, evolved from a normal chromosome pair, between which recombination stopped. We discuss why sex chromosomes evolve reduced recombination and why different parts of the chromosomes stopped recombining at different times, and outline some of the consequences of suppressed recombination, including the evolution of chromosome heteromorphism.
 
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Article
Plants exhibit complex mating patterns because of their immobility, hermaphroditism and reliance on vectors for pollen transfer. Research on plant mating attempts to determine who mates with whom in plant populations and how and why mating patterns become evolutionarily modified. Most theoretical models of mating-system evolution have focused on the fitness consequences of selling and outcrossing, stimulating considerable empirical work on the ecology and genetics of inbreeding depression. Less attention has been given to how the mechanics of pollen dispersal influence the transmission of self and outcross gametes. Recent work on the relation between pollen dispersal and mating suggests that many features of floral design traditionally interpreted as anti-selling mechanisms may function to reduce the mating costs associated with large floral displays.
 
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Population genetics studies using microsatellites, and data on their molecular dynamics, are on the increase. But, so far, no consensus has emerged on which mutation model should be used, though this is of paramount importance for analysis of population genetic structure. However, this is not surprising given the variety of microsatellite molecular motifs. Null alleles may be disturbing for population studies, even though their presence can be detected through careful population analyses, while homoplasy seems of little concern, at least over short evolutionary scales. Interspecific studies show that microsatellites are poor markers for phylogenetic inference. However, these studies are fuelling discussions on directional mutation and the role of selection and recombination in their evolution. Nonetheless, it remains true that microsatellites may be considered as good, neutral mendelian markers.
 
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Extinction and recolonization of populations may have various effects on the degree and distribution of genetic variation, but turnover is generally associated with low levels of among-population variation, in both 'classical' and other types of metapopulation. Therefore, adaptive evolution is unlikely to be promoted by selection among populations. Whether adaptation is promoted or slowed by population subdivision, with or without turnover, remains a subject of theoretical debate.
 
Article
The evolution of sex has been the focus of considerable attention during recent years. There is some consensus that the solution to the mystery is that sex either enables the creation and spread of advantageous traits (possibly parasite resistance) or helps to purge the genome of deleterious mutations. Recent experimental work has allowed testing of some of the assumptions underlying the theoretical models, most particularly whether interactions between genes are synergistic and whether the mutation rate is adequately high. However, although a variety of theories point out advantages to sex, most of them predict that a little sex and recombination can go a long way towards improving the fitness of a population, and it remains unclear why obligate sex is so common.
 
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Deforestation is occurring at an alarming rate in the lowland tropics. In many tropical regions, rain forest is restricted to small (<100 ha), isolated fragments. While only the preservation of large areas of tropical rain forest can safeguard the complete biota, recent research has shown that a substantial number of forest species can persist for decades in fragmented forest, though large vertebrates are susceptible to habitat fragmentation. Inevitably, small fragments will become the last refuges of many rainforest species that are on the brink of extinction. In areas with little rain forest remaining, fragments can be the 'seeds' from which to re-establish extensive forest.
 
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Article
The identification of management units (MUs) is central to the management of natural populations and is crucial for monitoring the effects of human activity upon species abundance. Here, we propose that the identification of MUs from population genetic data should be based upon the amount of genetic divergence at which populations become demographically independent instead of the current criterion that focuses on rejecting panmixia. MU status should only be assigned when the observed estimate of genetic divergence is significantly greater than a predefined threshold value. We emphasize the need for a demographic interpretation of estimates of genetic divergence given that it is often the dispersal rate of individuals that is the parameter of immediate interest to conservationists rather than the historical amount of gene flow.
 
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Dispersal is of central importance to population biology, behavioral ecology and conservation. However, because field studies are based on finite study areas, nearly all dispersal distributions for vertebrates currently available are biased, often highly so. The inadequacy of dispersal data obtained directly by traditional methods using population studies of marked individuals is highlighted by comparing the resulting distributions with dispersal estimates obtained by radio-tracking and by using genetic estimates of gene flow.
 
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Recent theory suggests that genetic correlations should help to predict the simultaneous response to selection of two or more traits, and much recent research has been directed towards understanding the sources of variation in genetic correlations. Genetic correlations can change from sample to sample, from species to species, from population to population, during the course of development and - within a population, at a fixed stage of development - from one environment to another. These are changes not only in magnitude but also in sign. Theory suggests that genetic correlations should not change sign when the two traits are tightly integrated by physiology or development. Patterns of change of genetic correlations are caused by differences in development and physiology, an understanding of which appears to be necessary to predict the response to selection in natural, heterogeneous environments.
 
Article
Reports of new and emerging coral diseases have proliferated in recent years. Such coral diseases are often cited as contributing to coral reef decline. Many of these diseases, however, have been described solely on the basis of field characteristics, and in some instances there is disagreement as to whether an observed coral condition is actually a disease. A disease pathogen has been identified for only three coral diseases, and for only two of these has the pathogen been shown (in the laboratory) to be the disease agent. In one case, the same disease name has been used for several widely varying coral syndromes, whereas in another multiple disease names have been applied to symptoms that may be caused by a single disease. Despite the current confusion, rapid progress is being made.
 
Article
Rapid evolution of interspecific interactions (during a timespan of about 100 years) has the potential to be an important influence on the ecological dynamics of communities. However, despite the growing number of examples, rapid evolution is still not a standard working hypothesis for many ecological studies on the dynamics of population structure or the organization of communities. Analysis of rapid evolution as an ecological process has the potential to make evolutionary ecology one of the most central of applied biological sciences.
 
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Anthropogenic introduction of species is homogenizing the earth's biota. Consequences of introductions are sometimes great, and are directly related to global climate change, biodiversity AND release of genetically engineered organisms. Progress in invasion studies hinges on the following research trends: realization that species' ranges are naturally dynamic; recognition that colonist species and target communities cannot be studied independently, but that species-community interactions determine invasion success; increasingly quantitative tests of how species and habitat characteristics relate to invasibility and impact; recognition from paleobiological, experimental and modeling studies that history, chance and determinism together shape community invasibility.
 
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Assignment methods, which use genetic information to ascertain population membership of individuals or groups of individuals, have been used in recent years to study a wide range of evolutionary and ecological processes. In applied studies, the first step of articulating the biological question(s) to be addressed should be followed by selection of the method(s) best suited for the analysis. However, this first step often receives less attention than it should, and the recent proliferation of assignment methods has made the selection step challenging. Here, we review assignment methods and discuss how to match the appropriate methods with the underlying biological questions for several common problems in ecology and conservation (assessing population structure; measuring dispersal and hybridization; and forensics and mixture analysis). We also identify several topics for future research that should ensure that this field remains dynamic and productive.
 
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Cooperative behaviour resulting from kin selection is widespread among animals and the ability to recognize and discriminate between kin and non-kin is a critical element in kin selection theory. Current evidence suggests that associative learning is the most likely mechanism of kin discrimination. However, surprisingly, there have been no experimental studies of the putative 'associative-learning period', the likely recognition mechanisms enabling fine discrimination between close and distant kin of similar familiarity, whether generic or individual cues are employed in kin recognition, and how recognition ability varies at different stages of a species' life history. Comparative studies of kin recognition and discrimination in cooperative and noncooperative species are also needed to shed light on the adaptive value of helping behaviour and to identify key factors in the evolution of cooperation.
 
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Amplified fragment length polymorphisms (AFLPs) are polymerase chain reaction (PCR)-based markers for the rapid screening of genetic diversity. AFLP methods rapidly generate hundreds of highly replicable markers from DNA of any organism; thus, they allow high-resolution genotyping of fingerprinting quality. The time and cost efficiency, replicability and resolution of AFLPs are superior or equal to those of other markers [allozymes, random amplified polymorphic DNA (RAPD), restriction fragment length polymorphism (RFLP), microsatellites], except that AFLP methods primarily generate dominant rather than co-dominant markers. Because of their high replicability and ease of use, AFLP markers have emerged as a major new type of genetic marker with broad application in systematics, pathotyping, population genetics, DNA fingerprinting and quantitative trait loci (QTL) mapping.
 
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What stops populations expanding into new territory beyond the edge of a range margin? Recent models addressing this problem have brought together population genetics and population ecology, and some have included interactions among species at range edges. Here, we review these models of adaptation at environmental or parapatric margins, and discuss the contrasting effects of migration in either swamping local adaptation, or supplying the genetic variation that is necessary for adaptation to continue. We illustrate how studying adaptation at range margins (both with and without hybridization) can provide insight into the genetic and ecological factors that limit evolution more generally, especially in response to current rates of environmental change.
 
Article
The nonrecombinant, uniparentally inherited nature of organelle genomes makes them useful tools for evolutionary studies. However, in plants, detecting useful polymorphism at the population level is often difficult because of the low level of substitutions in the chloroplast genome, and because of the slow substitution rates and intramolecular recombination of mtDNA. Chloroplast microsatellites represent potentially useful markers to circumvent this problem and, to date, studies have demonstrated high levels of intraspecific variability. Here, we discuss the use of these markers in ecological and evolutionary studies of plants, as well as highlighting some of the potential problems associated with such use.
 
Article
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Article
Damage to plants by herbivores is ubiquitous and sometimes severe. Tolerance is the capacity of a plant to maintain its fitness through growth and reproduction after sustaining herbivore damage. Recent physiological and ecological work indicates that tolerance mechanisms are numerous and varied. Some of the plant traits involved may reflect selection by herbivores, while others are likely to be by-products of selection for other ecological functions. Similarly, some tolerance mechanisms may participate In trade-offs with plant defence, while many do not. Regardless of its ultimate origin or physiological relationship to plant defence, tolerance often may Influence the evolution of plant defence and the composition of plant communities.
 
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Recent molecular phylogenies have changed our perspective on the evolution of echolocation in bats. These phylogenies suggest that certain bats with sophisticated echolocation (e.g. horseshoe bats) share a common ancestry with non-echolocating bats (e.g. Old World fruit bats). One interpretation of these trees presumes that laryngeal echolocation (calls produced in the larynx) probably evolved in the ancestor of all extant bats. Echolocation might have subsequently been lost in Old World fruit bats, only to evolve secondarily (by tongue clicking) in this family. Remarkable acoustic features such as Doppler shift compensation, whispering echolocation and nasal emission of sound each show multiple convergent origins in bats. The extensive adaptive radiation in echolocation call design is shaped largely by ecology, showing how perceptual challenges imposed by the environment can often override phylogenetic constraints.
 
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There is a long-standing debate in ecology concerning the relative importance of competition and predation in determining community structure. Recently, a novel twist has been added with the growing recognition that potentially competing species are often engaged in predator-prey interactions. This blend of competition and predation is called intraguild predation (IGP). The study of IGP will lead to a reconsideration of many classical topics, such as niche shifts, species exclusion and cascading interactions in food webs. Theoretical models suggest that a variety of alternative stable states are likely in IGP systems, and that intermediate predators should tend to be superior in exploitative competition. Many field studies support these expectations. IGP is also important in applied ecological problems, such as the conservation of endangered species and fisheries management.
 
Article
Recent research on diverse animal taxa has revealed that male adaptations to sperm competition often lead to a conflict with female interests. That is, male attempts to increase their own fertilization success can result in a reduction of female fitness. This sexual conflict has led to selection for a variety of female adaptations that apparently reduce male-imposed costs. Understanding the causes and consequences of sexual conflict arising from adaptations to sperm competition offers much potential for new insight into the coevolution of male and female sexual strategies.
 
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Nutritional conditions during key periods of development, when the architecture and modus operandi of the body become established, are of profound importance in determining the subsequent life-history trajectory of an organism. If developing individuals experience a period of nutritional deficit, they can subsequently show accelerated growth should conditions improve, apparently compensating for the initial setback. However, recent research suggests that, although compensatory growth can bring quick benefits, it is also associated with a surprising variety of costs that are often not evident until much later in adult life. Clearly, the nature of these costs, the timescale over which they are incurred and the mechanisms underlying them will play a crucial role in determining compensatory strategies. Nonetheless, such effects remain poorly understood and largely neglected by ecologists and evolutionary biologists.
 
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It has never been more urgent to identify the potential impacts of climate change. In our quest for information, we often rely on records that reveal how organisms and systems responded to past climates. A new study by Miller-Rushing et al. uses some unorthodox archive material (photographs and herbarium specimens) to examine changes in flowering phenology in the USA. Their approach suggests that we have failed to think-outside-the-box and have been overlooking a valuable resource for climate-impact research.
 
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In gynodioecious species, females and hermaphrodites coexist and the genetics of sex determination is usually nuclear cytoplasmic. Maintaining nuclear-cytoplasmic gynodioecy requires polymorphism for the feminizing genes (contained in the mitochondria) and the genes that restore male fertility (contained in the nucleus). This complex polymorphism depends, in part, on there being negative pleiotropic effects (i.e. costs) of the nuclear restorer alleles. Here, we combine information from theoretical studies and studies on the molecular action of restorer alleles in crops to interpret the probable costs of such alleles, and suggest how various aspects of the theoretical models could be tested. In doing so, we highlight how crops can be used to address evolutionary questions about the maintenance of nuclear-cytoplasmic gynodioecy.
 
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Partial migration, i.e.when one fraction of the population is migratory and the other sedentary, appears to be a widespread phenomenon among many animal taxa, ranging from insects to higher vertebrates. Partial migration in birds was first documented for several Holarctic populations many decades ago. The evolution and maintenance of this particular migratory system have only recently been more thoroughly examined, but our knowledge and understanding of the problem is still incomplete. Currently, one of the main concerns is the fitness balancing of the two behavioural alternatives, i.e. whether migrants and residents within a population are equally fit or if one of the categories is inferior and making 'the best of a bad situation'. Closely tied to this question is the proximate regulation of the migratory and sedentary habits. It has been suggested that a social dominance system might be powerful enough to keep this migration system going; alternatively, a pooulation might be divided into two genetically distinct morphs with different preprogrammed Migratory behaviours.
 
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Article
Recent studies suggest that populations and species often exhibit behavioral syndromes; that is, suites of correlated behaviors across situations. An example is an aggression syndrome where some individuals are more aggressive, whereas others are less aggressive across a range of situations and contexts. The existence of behavioral syndromes focuses the attention of behavioral ecologists on limited (less than optimal) behavioral plasticity and behavioral carryovers across situations, rather than on optimal plasticity in each isolated situation. Behavioral syndromes can explain behaviors that appear strikingly non-adaptive in an isolated context (e.g. inappropriately high activity when predators are present, or excessive sexual cannibalism). Behavioral syndromes can also help to explain the maintenance of individual variation in behavioral types, a phenomenon that is ubiquitous, but often ignored. Recent studies suggest that the behavioral type of an individual, population or species can have important ecological and evolutionary implications, including major effects on species distributions, on the relative tendencies of species to be invasive or to respond well to environmental change, and on speciation rates. Although most studies of behavioral syndromes to date have focused on a few organisms, mainly in the laboratory, further work on other species, particularly in the field, should yield numerous new insights.
 
Discordant gene trees suggest a hybrid origin for the Hawaiian silversword radiation. (a) A chloroplast DNA genealogy [40], and (b) a nuclear gene (ITS) sequence after concerted evolution [81] suggest that the Hawaiian silversword radiation is monophyletic. (c) A phylogeny based on a nuclear floral homeotic gene resolves two different North American tarweed species (in shaded boxes) as the closest relatives of the two different copies of the gene found in each species of the Hawaiian radiation [64]. The Hawaiian silverswords are allopolyploid whereas their North American relatives are diploid. Reproduced with permission from [40,64,81].
Article
Whether interspecific hybridization is important as a mechanism that generates biological diversity is a matter of controversy. Whereas some authors focus on the potential of hybridization as a source of genetic variation, functional novelty and new species, others argue against any important role, because reduced fitness would typically render hybrids an evolutionary dead end. By drawing on recent developments in the genetics and ecology of hybridization and on principles of ecological speciation theory, I develop a concept that reconciles these views and adds a new twist to this debate. Because hybridization is common when populations invade new environments and potentially elevates rates of response to selection, it predisposes colonizing populations to rapid adaptive diversification under disruptive or divergent selection. I discuss predictions and suggest tests of this hybrid swarm theory of adaptive radiation and review published molecular phylogenies of adaptive radiations in light of the theory.
 
Article
There is increasing interest in developing better predictive tools and a broader conceptual framework to guide the restoration of degraded land. Traditionally, restoration efforts have focused on re-establishing historical disturbance regimes or abiotic conditions, relying on successional processes to guide the recovery of biotic communities. However, strong feedbacks between biotic factors and the physical environment can alter the efficacy of these successional-based management efforts. Recent experimental work indicates that some degraded systems are resilient to traditional restoration efforts owing to constraints such as changes in landscape connectivity and organization, loss of native species pools, shifts in species dominance, trophic interactions and/or invasion by exotics, and concomitant effects on biogeochemical processes. Models of alternative ecosystem states that incorporate system thresholds and feedbacks are now being applied to the dynamics of recovery in degraded systems and are suggesting ways in which restoration can identify, prioritize and address these constraints.
 
Article
In plants, naturally occurring methylation of genes can affect the level of gene expression. Variation among individuals in the degree of methylation of a gene, termed epialleles, produces novel phenotypes that are heritable across generations. To date, ecologically important genes with methylated epialleles have been found to affect floral shape, vegetative and seed pigmentation, pathogen resistance and development in plants. Currently, the extent to which epiallelic variation is an important common contributor to phenotypic variation in natural plant populations and its fitness consequences are not known. Because epiallele phenotypes can have identical underlying DNA sequences, response to selection on these phenotypes is likely to differ from expectations based on traditional models of microevolution. Research is needed to understand the role of epialleles in natural plant populations. Recent advances in molecular genetic techniques could enable population biologists to screen for epiallelic variants within plant populations and disentangle epigenetic from more standard genetic sources of phenotypic variance, such as additive genetic variance, dominance variance, epistasis and maternal genetic effects.
 
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Neo-darwinists have long argued that parallel evolution, the repeated evolution of similar phenotypes in closely related lineages, is caused by the action of similar environments on alleles at many loci of small effect. A more controversial possibility is that the genetic architecture of traits initiates parallelism, sometimes through fixation of alleles of large effect. Recent research (by Cole et al., Colosimo et al., Cresko et al., and Shapiro et al.) offers the surprising insight that reduction in two armor traits of threespine stickleback is governed by independently segregating major loci as well as additional quantitative trait loci (QTL), and that alleles at the same major loci are associated with parallel phenotypes in globally distributed populations. This research suggests the emergence of a new and exciting vertebrate model system for evolutionary genetics.
 
Article
Ecological theory has been dominated by a focus on long-term or asymptotic behavior as a way to understand natural systems. Yet experiments are done on much shorter timescales, and the relevant timescales for ecological systems can also be relatively short. Thus, there is a mismatch between the timescales of most experiments and the timescales of many theoretical investigations. However, recent work has emphasized the importance of transient dynamics rather than long-term behavior in ecological systems, enabling the examination of forces that allow coexistence on ecological timescales. Through an examination of what leads to transients in ecological systems, a deeper appreciation of the forces leading to persistence or coexistence in ecological systems emerges, as well as a general understanding of how population levels can change through time.
 
Recent empirical studies showing genetic rescue effects a
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A series of important new theoretical, experimental and observational studies demonstrate that just a few immigrants can have positive immediate impacts on the evolutionary trajectory of local populations. In many cases, a low level of immigration into small populations has produced fitness benefits that are greater than those predicted by theoretical models, resulting in what has been termed 'genetic rescue'. However, the opposite result (reduced fitness) can also be associated with immigration of genetically divergent individuals. Central to our understanding of genetic rescue are complex interactions among fundamental concepts in evolutionary and population biology, including both genetic and non-genetic (environmental, behavioral and demographic) factors. Developing testable models to predict when genetic rescue is likely to occur is a daunting challenge that will require carefully controlled, multi-generation experiments as well as creative use of information from natural 'experiments'.
 
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Genitalia are conspicuously variable, even in closely related taxa that are otherwise morphologically very similar. Explaining genital diversity is a longstanding problem that is attracting renewed interest from evolutionary biologists. New studies provide ever more compelling evidence that sexual selection is important in driving genital divergence. Importantly, several studies now link variation in genital morphology directly to male fertilization success, and modern comparative techniques have confirmed predicted associations between genital complexity and mating patterns across species. There is also evidence that male and female genitalia can coevolve antagonistically. Determining mechanisms of genital evolution is an important challenge if we are to resolve current debate concerning the relative significance of mate choice benefits and sexual conflict in sexual selection.
 
Article
Emerging infectious diseases (EIDs) pose threats to conservation and public health. Here, we apply the definition of EIDs used in the medical and veterinary fields to botany and highlight a series of emerging plant diseases. We include EIDs of cultivated and wild plants, some of which are of significant conservation concern. The underlying cause of most plant EIDs is the anthropogenic introduction of parasites, although severe weather events are also important drivers of disease emergence. Much is known about crop plant EIDs, but there is little information about wild-plant EIDs, suggesting that their impact on conservation is underestimated. We conclude with recommendations for improving strategies for the surveillance and control of plant EIDs.
 
Article
Guidelines for submitting commentsPolicy: Comments that contribute to the discussion of the article will be posted within approximately three business days. We do not accept anonymous comments. Please include your email address; the address will not be displayed in the posted comment. Cell Press Editors will screen the comments to ensure that they are relevant and appropriate but comments will not be edited. The ultimate decision on publication of an online comment is at the Editors' discretion. Formatting: Please include a title for the comment and your affiliation. Note that symbols (e.g. Greek letters) may not transmit properly in this form due to potential software compatibility issues. Please spell out the words in place of the symbols (e.g. replace “α” with “alpha”). Comments should be no more than 8,000 characters (including spaces ) in length. References may be included when necessary but should be kept to a minimum. Be careful if copying and pasting from a Word document. Smart quotes can cause problems in the form. If you experience difficulties, please convert to a plain text file and then copy and paste into the form.
 
Article
Several observations and model calculations suggest that chemically mediated interactions can structure planktonic food webs. However, only recently have improvements in chemical methods, coupled with ecological assays, led to the characterization of chemical cues that affect the behaviour and/or physiology of planktonic organisms. We are currently beginning to elucidate if or how chemical signals can directly affect the interactions between species and even shape complex community structures in aquatic systems. Here, we highlight recent research on the nature and action of chemical signals in the pelagic marine and freshwater environments, with an emphasis on kairomones and defence metabolites.
 
Article
Scleractinian corals and their symbiotic dinoflagellate algae build massive, wave-resistant coral reefs that are pre-eminent in shallow tropical seas. This mutualism is especially sensitive to numerous environmental stresses, and has been disrupted frequently during the past decade. Increased seawater temperatures have been proposed as the most likely cause of coral reef bleaching, and it has been suggested that the recent large-scale disturbances are the first biological indication of global warming. This article describes recent bleaching events and their possible link with sea warming and other environmental stresses, and offers some speculation on the fate of coral reefs if the Earth enters a sustained period of warming.
 
Article
Population genetics has come of age. Three important components have come together: efficient techniques to examine informative segments of DNA, statistics to analyse DNA data and the availability of easy-to-use computer packages. Single-locus genetic markers and those that produce gene genealogies yield information that is truly comparable among studies. These markers answer biological questions most efficiently and also contribute to much broader investigations of evolutionary, population and conservation biology. For these reasons, single-locus and genealogical markers should be the focus of the intensive genetic data collection that has begun owing to the power of genetics in population biology.
 
Top-cited authors
Andrew Sih
  • University of California, Davis
Petr Pyšek
  • The Czech Academy of Sciences
Gordon Luikart
  • University of Montana
William J Sutherland
  • University of Cambridge
Simon G Potts
  • University of Reading