Determination of biogeographical range: an application of molecular phylogeography to the European pool frog Rana lessonae

Understanding how species are constrained within their biogeographical ranges is a central problem in evolutionary ecology. Essential prerequisites for addressing this question include accurate determinations of range borders and of the genetic structures of component populations. Human translocation of organisms to sites outside their natural range is one factor that increasingly complicates this issue. In areas not far beyond presumed natural range margins it can be particularly difficult to determine whether a species is native or has been introduced. The pool frog (Rana lessonae) in Britain is a specific example of this dilemma . We used variation at six polymorphic microsatellite loci for investigating the phylogeography of R. lessonae and establishing the affinities of specimens from British populations. The existence and distribution of a distinct northern clade of this species in Norway, Sweden and England infer that it is probably a long-standing native of Britain, which should therefore be included within its natural range. This conclusion was further supported by posterior probability estimates using Bayesian clustering. The phylogeographical analysis revealed unexpected patterns of genetic differentiation across the range of R. lessonae that highlighted the importance of historical colonization events in range structuring.     

应重视灾害生态学研究

一、灾害生态学概念灾害是一个关系概念。它是相对于一定的主体,表示某一事物的变化对主体的价值关系。通常,灾害被定义为事物的变化对主体造成损害。灾害在自然界是一种普遍现象,例如     

Back to the future: natural history and the way forward in modern fungal ecology

The growing power and increasing availability of molecular tools for identifying fungi in environmental samples has revolutionized the way that fungal ecologists work. As a result, more people from around the globe have jumped into the fungal community sequencing endeavor. Paradoxically, as these extensive datasets accumulate we are often at a loss for interpretation due to the lack of basic autecology and natural history information for most fungi. As a result we are in danger of learning less and about more and more. I suggest that one way forward in fungal ecology is through a modern version of fungal natural history, with a focus on holistic understanding of individual species and ecosystems, but driven by modern genomic and molecular tools. By combining the extensive data generated through environmental sequencing with an intensive, molecular-based natural history we can create a synergy that will propel fungal ecology forward.     

Reeves' Muntjac Muntiacus reevesi in Britain: their history, spread, habitat selection, and the role of human intervention in accelerating their dispersal

The origins, early history, captive populations, spread and habitat preferences of Reeves' Muntjac in Britain are reviewed. It is suggested that much of the published information on the history of Muntjac in Britain is based on misconceptions, and that each subsequent report has continued to promulgate a false impression on the origins, time-scale and pattern of spread of the species in Britain. Indian and Reeves' Muntjac were introduced to Woburn Park in Bedfordshire within a year of each other, and it appears that the Indian Muntjac did not thrive, at least in the decade following their introduction. How long they survived as a free-living species in Britain is unclear, but it was probably only a few years. However, there is some evidence to suggest that they might have persisted within the Park at Woburn until 1930. Following the first releases from Woburn in 1901, the numbers of free-living Reeves' Muntjac in Britain remained low until the 1920s, when populations were largely confined to the woods around Woburn, and possibly also around Tring in Hertfordshire. However, in the 1930s and 1940s there were further deliberate introductions in selected areas some distance from Woburn. As a consequence, the subsequent spread of Reeves' Muntjac was from several main foci, i.e. from the vicinity of Woburn, the Norfolk/Suffolk border, three sites in Northamptonshire, two sites in Oxfordshire and two in Warwickshire. The spread in the second half of this century has been aided by further deliberate and accidental releases, and by these means new populations continue to be established outside the main range. Thus the natural spread has been much less impressive than previously assumed; even in areas with established populations it takes a long time for Muntjac to colonize all the available habitat. Data from a number of areas in Britain suggest that the natural rate of spread is about 1 km a year, which is comparable to other species of deer in Britain. The many introductions have complicated an analysis of the habitat preferences of Reeves' Muntjac, and no clear trends could be found. It would appear that Reeves' Muntjac are less dependent on specific types of habitat than previously believed. Examination of the land-class preferences using resource selection indices showed that arable land classes were predominantly selected for, and that marginal upland land classes tended to be avoided. Subsequent logistic regression models based on the land classes selected (and to a lesser extent avoided) by Muntjac were able to predict accurately the current distribution of Reeves' Muntjac in Britain, and one of these, together with our knowledge of their history and spread, was used to infer those areas most likely to be colonized by Muntjac in the near future. The greatest potential for range expansion is in Kent and Sussex, and to a lesser extent north into Lincolnshire, Nottinghamshire and south Yorkshire, and west into Cheshire and north Shropshire. However, long-established populations in areas such as Betws-y-Coed in Wales show that Muntjac may persist in low numbers in atypical habitats. Future habitat changes, such as the planting of new woodlands, and continued deliberate and accidental releases, are likely to lead to population changes in addition to those predicted by the logistic regression model.     

From interesting details to dynamical relevance: toward more effective use of empirical insights in theory construction

A perennial challenge in ecology is to develop dynamical systems models that appropriately abstract and characterize the dynamics of natural systems. Deriving an appropriate model of system dynamics can be a long and iterative process whose outcome depends critically on the quality of empirical data describing the long‐term behavior of a natural system. Most ecological time series are insufficient to offer insight into the way organizational hierarchies and spatial scales are causally linked to natural system dynamics. Moreover, the classic tradition of hypothesis testing in ecology is not likely to lead to those key insights. This because empirical research is geared almost exclusively toward testing model predictions based on underlying causal relationships assumed by theorists. So, empirical research relies heavily on theory for guidance on what is or is not dynamically relevant. I argue here that it is entirely possible to reduce much of this guesswork involved with deciding on causal structure by giving empirical research a new role in theory development. In this role, natural history and field observations are used to develop stochastic, individual‐based and spatially explicit computational models or IBMs that can explore the range of contingency and complexity inherent in real‐world systems.
IBMs can be used to run simulations allowing deductions to be made about the causal linkages between organizational hierarchies, spatial scales, and dynamics. These deductions can be tested under field conditions using experiments that manipulate the putative causal structure and evaluate the dynamical consequences. The emerging insights from this stage can then be used to inspire an analytical construct that embodies the dynamically relevant scales and mechanisms. In essence, computational modeling serves as an intermediate step in theory development in that a wide range of possibly important biological details are considered and then reduced to a subset that is dynamically relevant.     

Haementeria costata (Hirudinea: Glossiphoniidae), a leech new to Britain

SUMMARY. The European leech Haementeria costata is recorded in Britain for the first time and is described in detail. A key is provided to distinguish H. costata from other species of leeches in Britain, and the literature on the ecology of H. costata is summarized.     

Restoration of Butterfly Populations in Britain

Over the last 150 years butterflies have declined rapidly in both distribution and abundance in Britain. The majority of species declines can be linked with widespread habitat destruction that has occurred over the same period. The resulting concern for their conservation has provided many examples of attempts at restoration, most of which have been unsuccessful. The most common reasons for failure appear to be unsuitability of the habitat or lack of knowledge of the species' requirements, but in many cases the recording of the attempt is inadequate for any assessment to be made. Case studies of recent restoration efforts for four butterfly species are used to illustrate that successful restoration depends on detailed study of the species1 ecology and–particularly–habitat requirements, the ability and the resources to manage the habitat to provide those requirements, and a formal scientific approach that maximizes the information gained from the restoration process. As more land in Britain is taken out of intensive agricultural use, opportunities will increase for restoration programs. Prominent and popular species indicative of particular habitats can act as a focus for restoration of the habitat as a whole.     

农牧交错带研究进展

农牧交错带是典型的生态脆弱区、贫困区和多民族聚居区,是我国生态安全的重要屏障.综述了农牧交错带发展的历史演变过程,分析了当前农牧交错带农牧业生产所面临的主要问题,建议今后对农牧交错带的研究应集中在以生态学为基础的跨学科研究;其热点领域应集中在农牧交错带生产力生态学、恢复生态学、界面生态学、放牧生态学,农牧交错带的健康诊断和价值评估等方面.其中生产力生态学是提高生产效率的保证,应加强农牧交错带农田草地系统耦合生产方式的研究;恢复生态学是治理退化农牧交错带的基础;界面生态学是剖析退化农牧交错带的切入点;放牧生态学是调控农牧交错带农田草地退化的手段;健康诊断有助于对农牧交错带进行客观的评价;价值评估则是对农牧交错带生态系统效益和服务的估算.     

The invertebrates of heather and heathland

WEBB, N. R., 1989. The invertebrates of heather and heathland. The southern heathlands of Great Britain have long been renowned amongst entomologists. The invertebrates fall into two groups: species which feed on heathland plants–about 40 in the case of Calluna–and a second group which depends on the particular physical conditions provided by heathland, such as hot dry sandy areas or the micro-topography of Sphagnum bogs. The ecology of representative examples will be described, and the effects of fragmentation and isolation of the heathlands on the distribution and abundance of invertebrates discussed.     

Ten years of invasion: Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Britain

1. Harmonia axyridis was first recorded in Britain in 2004. Two subsequent earlier records were received from 2003. 2. The UK Ladybird Survey, a citizen science initiative involving online recording, was launched in 2005 to encourage people across Britain to track the spread of H. axyridis. Tens of thousands of people have provided records of H. axyridis and other species of ladybirds, creating an invaluable dataset for large‐scale and long‐term research. Declines in the distribution of seven (of eight assessed) native species of ladybird have been demonstrated, and correlated with the arrival of H. axyridis, using the records collated through the UK Ladybird Survey. 3. Experimental research and field surveys have also contributed to our understanding of the ecology of H. axyridis and particularly the process of invasion. Harmonia axyridis arrived in Britain through dispersal and introduction events from regions in which it was deliberately released as a biological control agent. The rapid spread of this species has been attributed to its high natural dispersal capability by means of both flight and anthropogenic transport. A number of factors have contributed to the successful establishment and indeed dominance of this polymorphic species within aphidophagous guilds, including high reproductive capacity, intra‐guild predation, eurytopic nature, high resistance to natural enemies within the invaded range, and potentially phenotypic plasticity. 4. The global invasion by H. axyridis and subsequent research on this species has contributed to the general understanding of biological invasions.     

Fine‐scale spatial ecology drives kin selection relatedness among cooperating amoebae

Cooperation among microbes is important for traits as diverse as antibiotic resistance, pathogen virulence, and sporulation. The evolutionary stability of cooperation against “cheater” mutants depends critically on the extent to which microbes interact with genetically similar individuals. The causes of this genetic social structure in natural microbial systems, however, are unknown. Here, we show that social structure among cooperative Dictyostelium amoebae is driven by the population ecology of colonization, growth, and dispersal acting at spatial scales as small as fruiting bodies themselves. Despite the fact that amoebae disperse while grazing, all it takes to create substantial genetic clonality within multicellular fruiting bodies is a few millimeters distance between the cells colonizing a feeding site. Even adjacent fruiting bodies can consist of different genotypes. Soil populations of amoebae are sparse and patchily distributed at millimeter scales. The fine‐scale spatial structure of cells and genotypes can thus account for the otherwise unexplained high genetic uniformity of spores in fruiting bodies from natural substrates. These results show how a full understanding of microbial cooperation requires understanding ecology and social structure at the small spatial scales microbes themselves experience.     

Sensory ecology of salps (Tunicata,thaliacea): More questions than answers

There is still relatively little known about the natural history of gelatinous animals in the plankton, and their sensory ecology remains largely a matter of surmise, based on limited morphological, physiological and behavioral data. Pelagic tunicates are among the most widely distributed and abundant of the gelatinous zooplank‐ton, and display a range of behavior that is apparently cued by aspects of their environment. Different kinds of information may be important for different scales of behavior. Feeding and predator avoidance are likely to be affected by near‐field stimuli from visual, chemical or mechanical sources, while far‐field information such as gravity, light, temperature, or pressure are likely to cue behavior spanning larger time and space scales, such as vertical or ontogenetic migration, aggregation and reproductive cycles. A variety of sensory structures have been described in pelagic tunicates, including photoreceptors of varying complexity, and several structures that have been suggested to be mechano‐ or chemoreceptors. Focussing on salps, this paper describes behavior that depends on sensory information, reviews the known structure and function of sensory receptors, and suggests some hypotheses on mechanisms defining the sensory ecology of these planktonic organisms.     

The incomplete natural history of mitochondria

Mitochondrial DNA (mtDNA) has been used to study molecular ecology and phylogeography for 25 years. Much important information has been gained in this way, but it is time to reflect on the biology of the mitochondrion itself and consider opportunities for evolutionary studies of the organelle itself and its ecology, biochemistry and physiology. This review has four sections. First, we review aspects of the natural history of mitochondria and their DNA to show that it is a unique molecule with specific characteristics that differ from nuclear DNA. We do not attempt to cover the plethora of differences between mitochondrial and nuclear DNA; rather we spotlight differences that can cause significant bias when inferring demographic properties of populations and/or the evolutionary history of species. We focus on recombination, effective population size and mutation rate. Second, we explore some of the difficulties in interpreting phylogeographical data from mtDNA data alone and suggest a broader use of multiple nuclear markers. We argue that mtDNA is not a sufficient marker for phylogeographical studies if the focus of the investigation is the species and not the organelle. We focus on the potential bias caused by introgression. Third, we show that it is not safe to assume a priori that mtDNA evolves as a strictly neutral marker because both direct and indirect selection influence mitochondria. We outline some of the statistical tests of neutrality that can, and should, be applied to mtDNA sequence data prior to making any global statements concerning the history of the organism. We conclude with a critical examination of the neglected biology of mitochondria and point out several surprising gaps in the state of our knowledge about this important organelle. Here we limelight mitochondrial ecology, sexually antagonistic selection, life-history evolution including ageing and disease, and the evolution of mitochondrial inheritance.     

Notes On Strand Plants. II. Cakile Maritima,Scop

Summary

Buxbaumia aphylla is a rare and enigmatic moss in Britain where it is found regularly and in sizeable populations only on colliery debris (‘bings’) in central Scotland. Its habitat preferences and ecology are described from a range of sites. It has persisted in quantity in several localities for over 20 years, but in other apparently suitable sites it is absent. Destruction and landscaping of bings are seen as the major threat to the species in Scotland.     

A guide to practical babooning: Historical,social, and cognitive contingency

As ecologically adaptable animals, baboons are distributed widely across Africa, and display a variety of morphological and behavioral differences that reflect both local ecology and a complex evolutionary history. As long‐lived, slowly reproducing animals, baboons face numerous ecological challenges to survival and successful reproduction. As group‐living animals, the social world presents an equally diverse array of challenges that require the negotiation of individual needs within the constraints imposed by others. Understanding how all these facets of baboon evolutionary history, life history, ecology, sociality, and cognition fit together is an enormous but engaging challenge, and despite one hundred years of study, it is clear there is a still much to learn about the various natural histories of baboons. What also is clear, however, is that an appreciation of contingency holds the key to understanding all these facets of baboon evolution and behavior. In what follows, I hope to illustrate exactly what I mean by this, highlighting along the way that history is not to be ignored, variability is information and not merely “noise”, and that behavioral and cognitive complexity can be two very different things.     

Phylogenetic approaches for studying diversification

Estimating rates of speciation and extinction, and understanding how and why they vary over evolutionary time, geographical space and species groups, is a key to understanding how ecological and evolutionary processes generate biological diversity. Such inferences will increasingly benefit from phylogenetic approaches given the ever‐accelerating rates of genetic sequencing. In the last few years, models designed to understand diversification from phylogenetic data have advanced significantly. Here, I review these approaches and what they have revealed about diversification in the natural world. I focus on key distinctions between different models, and I clarify the conclusions that can be drawn from each model. I identify promising areas for future research. A major challenge ahead is to develop models that more explicitly take into account ecology, in particular the interaction of species with each other and with their environment. This will not only improve our understanding of diversification; it will also present a new perspective to the use of phylogenies in community ecology, the science of interaction networks and conservation biology, and might shift the current focus in ecology on equilibrium biodiversity theories to non‐equilibrium theories recognising the crucial role of history.     

Natural history of model organisms: The secret (group) life of Drosophila melanogaster larvae and why it matters to developmental ecology

1. Model organisms such as Drosophila melanogaster have been key tools for advancing our fundamental and applied knowledge in biological and biomedical sciences. However, model organisms have become intertwined with the idea of controlled and stable laboratory environments, and their natural history has been overlooked.
2. In holometabolous insects, lack of natural history information on larval ecology has precluded major advances in the field of developmental ecology, especially in terms of manipulations of population density early in life (i.e., larval density). This is because of relativistic and to some extent, arbitrary methodologies employed to manipulate larval densities in laboratory studies. As a result, these methodologies render comparisons between species impossible, precluding our understanding of macroevolutionary responses to population densities during development that can be derived from comparative studies.
3. We recently proposed a new conceptual framework to address this issue, and here, we provide the first natural history investigation of Drosophila melanogaster larval density under such framework. First, we characterized the distribution of larval densities in a wild population of D. melanogaster using rotting apples as breeding substrate in a suburban area in Sweden.
4. Next, we compiled the commonly used methodologies for manipulating larval densities in laboratory studies from the literature and found that the majority of laboratory studies identified did not manipulate larval densities below or above the densities observed in nature, suggesting that we have yet to study true life history and physiological responses to low and high population densities during D. melanogaster development.
5. This is, to our knowledge, the first direct natural history account of larval density in nature for this model organism. Our study paves the way for a more integrated view of organismal biology which re‐incorporates natural history of model organisms into hypothesis‐driven research in developmental ecology.

     

The Human Dimensions of Geomorphological Work in Britain

The transfer of materials from the natural environment to the urban and industrially built environment produces two broad impacts on the landscape: a removal of materials from the earth's surface (a change in geomorphology) and the accumulation of a stock of concrete and other materials elsewhere in cities and industrial zones (a change in urban morphology). Thus, industrial activity transforms natural landscapes and, in doing so, has to be considered to be a geological and geomorphological agent. On the global scale, the deliberate shift of around 57,000 Mt (megatons)/yr of materials through mineral extraction processes exceeds the annual transport of sediment to the oceans by rivers (some 22,000 Mt/yr) by almost a factor of three. On the island of Britain, the total deliberate shift of earth-surface materials is between 688 and 972 Mt/yr, depending on whether or not the replacement of overburden in opencast coal mining is taken into account. The export of sediment to the oceans by rivers is only 10 Mt/yr whereas the export of materials in solution is about 40 Mt/yr, making the deliberate materials shift nearly 14 times larger than the shift caused by natural processes. Processes examined by industrial ecology, such as direct excavation, urban development, and waste dumping are those most driving changes in the shape of the British landscape today. These transformations pose added costs. Industrial ecology will produce an understanding of the hidden costs associated with these transformations. Such an understanding will help in planning and encouraging the reuse of materials everywhere and in identifying the key areas for intervention to reduce off-site geomorphological impacts and costs.     

Competition as a source of constraint on life history evolution in natural populations

Competition among individuals is central to our understanding of ecology and population dynamics. However, it could also have major implications for the evolution of resource-dependent life history traits (for example, growth, fecundity) that are important determinants of fitness in natural populations. This is because when competition occurs, the phenotype of each individual will be causally influenced by the phenotypes, and so the genotypes, of competitors. Theory tells us that indirect genetic effects arising from competitive interactions will give rise to the phenomenon of ‘evolutionary environmental deterioration'', and act as a source of evolutionary constraint on resource-dependent traits under natural selection. However, just how important this constraint is remains an unanswered question. This article seeks to stimulate empirical research in this area, first highlighting some patterns emerging from life history studies that are consistent with a competition-based model of evolutionary constraint, before describing several quantitative modelling strategies that could be usefully applied. A recurrent theme is that rigorous quantification of a competition''s impact on life history evolution will require an understanding of the causal pathways and behavioural processes by which genetic (co)variance structures arise. Knowledge of the G-matrix among life history traits is not, in and of itself, sufficient to identify the constraints caused by competition.     

Biogeography and ecology: towards the integration of two disciplines

Although ecology and biogeography had common origins in the natural history of the nineteenth century, they diverged substantially during the early twentieth century as ecology became increasingly hypothesis-driven and experimental. This mechanistic focus narrowed ecology''s purview to local scales of time and space, and mostly excluded large-scale phenomena and historical explanations. In parallel, biogeography became more analytical with the acceptance of plate tectonics and the development of phylogenetic systematics, and began to pay more attention to ecological factors that influence large-scale distributions. This trend towards unification exposed problems with terms such as ‘community’ and ‘niche,’ in part because ecologists began to view ecological communities as open systems within the contexts of history and geography. The papers in this issue represent biogeographic and ecological perspectives and address the general themes of (i) the niche, (ii) comparative ecology and macroecology, (iii) community assembly, and (iv) diversity. The integration of ecology and biogeography clearly is a natural undertaking that is based on evolutionary biology, has developed its own momentum, and which promises novel, synthetic approaches to investigating ecological systems and their variation over the surface of the Earth. We offer suggestions on future research directions at the intersection of biogeography and ecology.