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Species distribution models ( SDMs) are used to inform a range of ecological, biogeographical and conservation applications. However, users often underestimate the strong links between data type, model output and suitability for end-use. We synthesize current knowledge and provide a simple framework that summarizes how interactions between data type and the sampling process (i.e. imperfect detection and sampling bias) determine the quantity that is estimated by a SDM. We then draw upon the published literature and simulations to illustrate and evaluate the information needs of the most common ecological, biogeographical and conservation applications of SDM outputs. We find that, while predictions of models fitted to the most commonly available observational data (presence records) suffice for some applications, others require estimates of occurrence probabilities, which are unattainable without reliable absence records. Our literature review and simulations reveal that, while converting continuous SDM outputs into categories of assumed presence or absence is common practice, it is seldom clearly justified by the application's objective and it usually degrades inference. Matching SDMs to the needs of particular applications is critical to avoid poor scientific inference and management outcomes. This paper aims to help modellers and users assess whether their intended SDM outputs are indeed fit for purpose. [ABSTRACT FROM AUTHOR]

Most ethnographers visualize their fieldwork study vis-à-vis their long-term commitment to a bounded sociospatial context-an 'ecology.' In this manner, the majority of ethnographic studies are presented as studies not only of practices but also of recognizable physical ecologies that breathe life into the practices-for example, homes, ghettos, firms, schools, and so on. In the pages that follow, I consider the ways in which the status of place has shifted in urban sex work. The shifting commerce of sexual services in New York enables me to open up a set of methodological issues about the role of space in ethnographic work. One in particular is at the core of this paper: namely, because so many ethnographic labors begin with the selection of a field site, what conceptual issues arise that fieldworkers must pay attention to vis-à-vis that decision? For example, the field site may change, the field site may itself be shaped by wider societal forces, and it may be simply dissolve over time. How does any of this impact a technique that is premised on the dependability of 'sitting' so that others may be dependably followed? I draw on the notion of 'strategic action fields' to present an alternative analytic framework, one more useful for the challenges ethnographers face. [ABSTRACT FROM AUTHOR]

615I.615II.616III.618IV.622V.625VI.627VII.628628References628 Summary: Invasion science is a very active subdiscipline of ecology. However, some scientists contend that theoretical integration has been limited and that predictive power remains weak. This paper, focusing on plants, proposes a new multi‐pronged research strategy that builds on recent advances in invasion science. More intensive studies on particular model organisms and ecosystems are needed to improve our understanding of the full suite of interacting factors that influence invasions (‘model system research’). At the same time, comparative studies across many study systems are essential for unravelling the context‐dependencies of insights that emerge from particular studies (‘multi‐site studies’); and quantitative synthesis based on large datasets should be constrained to well‐defined theoretical domains (‘focused meta‐analysis’). We also suggest ways for better integration of information about species biology and ecosystem characteristics (‘invasion syndromes’). We expect that a resulting theory of invasions will need to be conceived as a somewhat heterogeneous conglomerate of elements of varying generality and predictive power: laws that apply to well‐specified domains, general concepts and theoretical frameworks that can guide thinking in research and management, and in‐depth knowledge about the drivers of particular invasions. [ABSTRACT FROM AUTHOR]

The article discusses the significance of citing references in research works pertaining to ecology and the environment. According to the author, research works and such other papers about ecology the foundation of ecological science. The credibility of scientific work depends on its verifiable citations which functions to support the arguments presented in the paper. However, the author argues that there is no existing studies which explore the suitability or even fidelity of citations in ecological journals.

The article comments on the paper "Riparian Zones Increase Regional Species Richness by Harboring Different, Not More, Species," by John L. Salbo and Candan U. Soykan. The authors of the paper found no general pattern of higher species richness in riparian compared to upland areas for either local or cumulative diversity. However, they cannot state anything at all regarding the level of the contribution of species from the riparian areas to the regional species pool.

Aim When faced with dichotomous events, such as the presence or absence of a species, discrimination capacity (the ability to separate the instances of presence from the instances of absence) is usually the only characteristic that is assessed in the evaluation of the performance of predictive models. Although neglected, calibration or reliability (how well the estimated probability of presence represents the observed proportion of presences) is another aspect of the performance of predictive models that provides important information. In this study, we explore how changes in the distribution of the probability of presence make discrimination capacity a context-dependent characteristic of models. For the first time, we explain the implications that ignoring the context dependence of discrimination can have in the interpretation of species distribution models. Innovation In this paper we corroborate that, under a uniform distribution of the estimated probability of presence, a well-calibrated model will not attain high discrimination power and the value of the area under the curve will be 0.83. Under non-uniform distributions of the probability of presence, simulations show that a well-calibrated model can attain a broad range of discrimination values. These results illustrate that discrimination is a context-dependent property, i.e. it gives information about the performance of a certain algorithm in a certain data population. Main conclusions In species distribution modelling, the discrimination capacity of a model is only meaningful for a certain species in a given geographic area and temporal snapshot. This is because the representativeness of the environmental domain changes with the geographical and temporal context, which unavoidably entails changes in the distribution of the probability of presence. Comparative studies that intend to generalize their results only based on the discrimination capacity of models may not be broadly extrapolated. Assessment of calibration is especially recommended when the models are intended to be transferred in time or space. [ABSTRACT FROM AUTHOR]

Understanding the determinants of species' distributions and abundances is a central theme in ecology. The development of statistical models to achieve this has a long history and the notion that the model should closely reflect underlying scientific understanding has encouraged ecologists to adopt complex statistical methods as they arise. In this paper we describe a Bayesian hierarchical model that reflects a conceptual ecological model of multi-scaled environmental determinants of riverine fish species' distributions and abundances. We illustrate this with distribution and abundance data of a small-bodied fish species, the Empire gudgeon Hypseleotris galii, in the Mary and Albert Rivers, Queensland, Australia. Specifically, the model sought to address; 1) the extent that landscape-scale abiotic variables can explain the species' distribution compared to local-scale variables, 2) how local-scale abiotic variables can explain species' abundances, and 3) how are these local-scale relationships mediated by landscape-scale variables. Overall, the model accounted for around 60% of variation in the distribution and abundance of H. galii. The findings show that the landscape-scale variables explain much of the distribution of the species; however, there was considerable improvement in estimating the species' distribution with the addition of local-scale variables. There were many strong relationships between abundance and local-scale abiotic variables; however, several of these relationships were mediated by some of the landscape-scale variables. The extent of spatial autocorrelation in the data was relatively low compared to the distances among sampling reaches. Our findings exemplify that Bayesian statistical modelling provides a robust framework for statistical modelling that reflects our ecological understanding. This allows ecologists to address a range of ecological questions with a single unified probability model rather than a series of disconnected analyses. [ABSTRACT FROM AUTHOR]

This paper studies how anglers in northern England invoke models of equilibrium and 'the balance of nature' in making sense of the water environments where they regularly fish, and how they use these models as norms or ideals when designing environmental management, alongside an emphasis on natural agency and unpredictability. Like other publics, anglers are shown to be a heterogeneous group in how they think about nature and their 'lay ecologies' reflect the problematic way in which equilibrium is normalised in science and policy more generally, showing similarities with professional environmental managers. But anglers are unusual publics, because their lay ecologies are put to work in collectively managing water environments, through stocking, culling and habitat management. Thus anglers' environmental knowledge practices co-produce the environments in which they develop their lay ecologies, making their models of nature and equilibrium important both conceptually and materially. [ABSTRACT FROM AUTHOR]

• Premise of the Study: Post-anthesis functionality of persistent perianth parts has rarely been investigated, but available evidence suggests that perianth persistence may not always have an adaptive value. Given the high occurrence of the trait, that it may sometimes be maladaptive is an intriguing possibility and deserves exploration. This paper tests the hypothesis that the fitness value of corolla persistence after anthesis depends on ecological context, specifically the abundance of fruit predators and pollinators. • Methods: The study was conducted on Narcissus longispathus, a species in which corolla marcescence is apparently maladaptive because withered corollas provide a shelter for fruit-predatory lepidopteran larvae. By experimentally manipulating corolla persistence, presence of fruit predators, and pollination, I tested whether variation in ecological scenario led to concomitant variation in the sign and magnitude of the effects of corolla marcescence on fecundity. • Key Results: Persistent corollas were detrimental to fecundity when plants were exposed to larvae, but not when larvae were excluded. Pollination and herbivory had nonadditive effects on the fecundity consequences of corolla marcescence, the strongest detrimental effects of corolla persistence occurring for the "exposed to larvae + supplementary pollination" treatment combination. • Conclusions: The hypothesis that ecological context is a major determinant of the fitness value of corolla marcescence was supported. In N. longispathus, corolla marcescence will be a maladaptive trait in situations in which pollinators and fruit predators are simultaneously abundant, but will be a neutral character in the absence of fruit predators, irrespective of pollinator service. [ABSTRACT FROM AUTHOR]

• Anthropogenic nitrogen (N) addition may substantially alter the terrestrial N cycle. However, a comprehensive understanding of how the ecosystem N cycle responds to external N input remains elusive. • Here, we evaluated the central tendencies of the responses of 15 variables associated with the ecosystem N cycle to N addition, using data extracted from 206 peer-reviewed papers. • Our results showed that the largest changes in the ecosystem N cycle caused by N addition were increases in soil inorganic N leaching (461%), soil NO3- concentration (429%), nitrification (154%), nitrous oxide emission (134%), and denitrification (84%). N addition also substantially increased soil NH4+ concentration (47%), and the N content in belowground (53%) and aboveground (44%) plant pools, leaves (24%), litter (24%) and dissolved organic N (21%). Total N content in the organic horizon (6.1%) and mineral soil (6.2%) slightly increased in response to N addition. However, N addition induced a decrease in microbial biomass N by 5.8%. • The increases in N effluxes caused by N addition were much greater than those in plant and soil pools except soil NO3-, suggesting a leaky terrestrial N system. [ABSTRACT FROM AUTHOR]

Integrated conservation and development projects (ICDPs) are common place in the field of biodiversity conservation. However, there is little evidence in the wider literature on the successes of these projects, with failure attributed to a range of factors, including a bias on either conservation or development, weak assumptions and limited monitoring and evaluation. In this paper, we evaluate an ICDP in the North Rupununi district of Guyana. Using a systems viability approach, we show how assessing the project and the nested systems within which it is operating reveals numerous human and institutional capacity issues which could have been managed better if highlighted at the project development stage. We conclude with the proposal that a systems viability approach to ICDP development, monitoring and evaluation encourages greater learning and adaptive management processes for increasing the long-term impact of ICDPs. [ABSTRACT FROM AUTHOR]

1. The area or size of an ecosystem affects the acquisition, storage and redistribution of energy and matter. Patch size reduction due to natural or anthropogenic habitat loss will not only modify species distribution and patch structure but also affect the ecosystem processes that are, in part, responsible for patch persistence. 2. In a fog-dependent forest ecosystem, trees and their architectures play essential roles in capturing and redistributing water from collection surfaces. In this paper, we address the question of how forest patch size and structure interact to determine fog water inputs and storage in a fog-inundated, coastal ecosystem in semi-arid Chile (30°S). 3. Six forest patches ranging in area from 0·2 to 36 ha on a coastal mountaintop of Fray Jorge National Park were characterized using 0·1 ha plots laid down at the centre of each forest patch. In each patch, we assessed tree basal area as a measure of forest structure, recorded daily air temperature and humidity, measured water influx from stemflow and throughfall (water that has passed through the forest canopy). Soil and litter gravimetric water contents were used as a measure of storage. 4. Total tree basal area per hectare was positively related to patch area, despite some variation at the species level. Mean and maximum air temperatures inside the patches were inversely related to patch size, with maximum temperatures differing by 2 °C on average. Annual fog water capture by trees within forest patches (net throughfall) was estimated in 296·1 mm after rain flux (about 122 mm) was subtracted. Throughfall volume and patch area were uncorrelated, but stemflow volume, soil and litter water contents scaled positively with patch area, showing a functional link between water interception and ecosystem retention. 5. Our study shows that ecosystem area in this mosaic of fog-dependent temperate forest patches can modify water fluxes and storage capacity of the ecosystem. This finding has important consequences for fragmented landscapes, where large continuous forests are fragmented into smaller patches, affecting not only the persistence of species but also the continuity of critical ecosystem processes. [ABSTRACT FROM AUTHOR]

Issues of residual spatial autocorrelation (RSA) and spatial scale are critical to the study of species-environment relationships, because RSA invalidates many statistical procedures, while the scale of analysis affects the quantification of these relationships. Although these issues independently are.widely covered in the literature, only sparse attention is giver to their integration. This paper focuses on the interplay between RSA and the spatial scaling of species-environment relationships. Using a hypothetical species in an artificial landscape, we show that a misipatch between the scale of analysis and the scale of a species' response to its environment leads to a decrease in the portion of variation explained by environmental predictors. Moreover, it results in RSA and biased regression coefficients. This bias stems from error-predictor dependencies due to the scale mismatch, the magnitude of which depends on the interaction between the scale of landscape heterogeneity and the scale of a species' response to this heterogeneity. We show that explicitly considering scale effects on RSA can reveal the characteristic scale of a species' response to its environment. This is important, because the estimation of species-environment relationships using spatial regression methods proves to be erroneous in case of a scale mismatch, leading to spurious conclusions when scaling issues are not explicitly considered. The findings presented here highlight the importance of examining the appropriateness of the spatial scales used in analyses, since scale mismatches affect the rigor of statistical analyses and thereby the ability to understand the processes underlying spatial patterning in ecological phenomena. [ABSTRACT FROM AUTHOR]

This paper provides a panbiogeographical analysis of the endemic plant families and the palms of New Caledonia. There are three endemic plant families in New Caledonia and several genera that were previously recognized as endemic families. Of these taxa, some are sister to widespread Northern Hemisphere or global groups ( Canacomyrica, Austrotaxus, Amborella). The others belong to trans-Indian Ocean groups ( Strasburgeria), trans-tropical Pacific groups ( Oncotheca) or Tasman Sea/Coral Sea groups ( Phelline, Paracryphia) that are sister to widespread Northern Hemisphere or global groups. In palms, the four clades show allopatric regional connections in, respectively: (1) western Indonesia, Malaysia and Thailand; (2) Vanuatu/Fiji and the southern Ryukyu Islands near Taiwan; (3) the western Tasman/Coral Sea (eastern Australia, New Guinea and the Solomon Islands); and (4) the eastern Tasman/Coral Sea (Lord Howe and Norfolk Islands, New Zealand, Vanuatu, Fiji and the Solomon Islands). The four clades thus belong to different centres of endemism that overlap in New Caledonia. The patterns are attributed not to chance dispersal and adaptive radiation but to the different histories of the eight terranes that fused to produce modern New Caledonia. Trans-tropical Pacific connections can be related to the Cretaceous igneous plateaus that formed in the central Pacific and were carried, with plate movement, west to the Solomon Islands and New Zealand, and east to Colombia and the Caribbean. [ABSTRACT FROM AUTHOR]

We believe that the language commonly used in teaching actually hinders the creation of conservation literacy. We examined four frequently used ecology and environmental studies textbooks and considered the ways in which commonly used language can obscure or enhance an understanding of ecology and conservation. Specifically, we used the Sapir–Whorf hypothesis (a.k.a. linguistic relativity) and framing theory to examine the approaches reflected in three elements of the texts: introductions and treatment of two key ecological concepts (matter cycling and energy). Language used in the texts contained implicit metaphors that portrayed nature as a resource; resisted ecological realities, such as the finite nature of matter and the loss of energy with each transformation; and fundamentally served to separate humans from nature. Although the basis of conservation literacy is understanding of the complexity of ecological systems, culturally based communication as exemplified in these texts does not encourage students or educators to recognize the feedback loops that clarify human membership in the ecosystem. Consequently, the language used to teach ecology perpetuates the idea that humans exist outside of its laws. With this paper, we hope to initiate a dialogue about how to retool the language used in teaching and communicating about ecology such that it resonates with, rather than undermines, conservation. [ABSTRACT FROM AUTHOR]

Rural communities all over South East Asia are facing major challenges as they try to shape their economic futures in ways that will increase wellbeing for all. This paper argues that researchers who describe and explain rural change play a powerful role in shaping imagined futures and the practices of local development. We foreground the theoretical choices made in representing rural change and call for a rethinking of the dynamics of transformation, one that highlights complexity, uncertainty and possibility. Following Robert Chambers and Jane Jacobs we draw on ecological representations of habitat maintenance, diversity and interdependent development and co-development to help inspire new ways of thinking and performing change. We illustrate theoretical and practical choices that can strengthen resilience in rural communities, using examples from our action research intervention in the Philippines. [ABSTRACT FROM AUTHOR]

1. Here we present an introduction to this issue’s Special Feature arising from the British Ecological Society Symposium: Facilitation in Plant Communities (20–22 April 2009). 2. Papers in the Special Feature demonstrate the benefits that arise from cross-system application of general concepts, for example, the well-known stress gradient hypothesis. Such comparisons challenge our definition of facilitation, as well as our pre-conceptions on the nature of intermediary organisms. 3. We suggest that under some circumstances a clear definition of the two-way nature of interactions is essential, e.g. when considering the evolutionary implications of facilitation. In other cases, however, we can perhaps be more relaxed, e.g. when facilitation is a component of conservation ecology. 4. Synthesis. Overall we believe that establishing facilitation as an independent concept has driven substantial progress towards a clearer understanding of how ecological systems work. Through the links established by work such as that presented in this Special Feature, we believe this field will continue to make rapid progress and aid ecological understanding in general. [ABSTRACT FROM AUTHOR]

Avian scavengers are common and active in the social life of southern Ghana, yet few studies consider both the ecological factors for avian presence and the avian–human interactions from human gender and age perspectives, and compare avian behaviour in both human-dominated and natural landscapes. This paper examines interactions between people, hooded vultures and pied crows in Accra and Kumasi, Ghana using both ecological and social research methods. Land use was classified for species presence into meat and waste production, vegetable marketing, non-food production, residential and central business areas, green spaces and rural areas. One hundred and eighty-four people were interviewed, classified according to age and gender. Hooded vultures and pied crows were more common in urban than rural areas, and their presence was positively correlated with human numbers. Birds were most common in meat and waste production areas, but also foraged for street discards in non-food production and residential areas, and were most rare in rural areas. Bird consumption of waste was viewed positively, while eating of other foods, close proximity and unusual behaviours were viewed negatively. Both species, especially the larger vultures, were feared as spiritual agents, this measured by odd behaviours. Women and older people had stronger beliefs, due to cultural conditioning. These human perspectives and reactions influenced avian presence. This study contributes to urban avian ecology, socio-cultural studies and urban planning. [ABSTRACT FROM AUTHOR]

Research on ecological communities, and plant–pollinator mutualistic networks in particular, has increasingly benefited from the theory and tools of complexity science. Nevertheless, up to now there have been few attempts to investigate the interplay between the structure of real pollination networks and their dynamics. This study is one of the first contributions to explore this issue. Biological invasions, of major concern for conservation, are also poorly understood from the perspective of complex ecological networks. In this paper we assess the role that established alien species play within a host community by analyzing the temporal changes in structural network properties driven by the removal of non-native plants. Three topological measures have been used to represent the most relevant structural properties for the stability of ecological networks: degree distribution, nestedness, and modularity. Therefore, we investigate for a detailed pollination network, 1) how its dynamics, represented as changes in species abundances, affect the evolution of its structure, 2) how topology relates to dynamics focusing on long-term species persistence; and 3) how both structure and dynamics are affected by the removal of alien plant species. Network dynamics were simulated by means of a stochastic metacommunity model. Our results showed that established alien plants are important for the persistence of the pollination network and for the maintenance of its structure. Removal of alien plants decreased the likelihood of species persistence. On the other hand, both the full network and the subset native network tended to lose their structure through time. Nevertheless, the structure of the full network was better preserved than the structure of the network without alien plants. Temporal topological shifts were evident in terms of degree distribution, nestedness, and modularity. However the effects of removing alien plants were more pronounced for degree distribution and modularity of the network. Therefore, elimination of alien plants affected the evolution of the architecture of the interaction web, which was closely related to the higher species loss found in the network where alien plants were removed. [ABSTRACT FROM AUTHOR]

An improved understanding of the rapid nitrogen fluxes that occur in plant rhizospheres has not been adequately incorporated into the study of how soil N availability and plant N uptake control a number of important ecological processes. One reason for this is that current methods that measure N availability do not account for the rapid exchange of resources between roots and their closely associated microbial communities. In this paper, we review the tight interactions between roots and microbes and discuss why ignoring the significance of these interactions has led to unrepresentative estimates of N availability in intact plant communities and an incomplete understanding of the environmental factors that control plant-available N. We also explain why current standard methods to measure soil N availability do not account for important rhizospheric processes. Finally, we issue a challenge to develop new methods that will estimate soil N transformations in intact plant communities and offer some potential approaches that may help catalyze this effort. [ABSTRACT FROM AUTHOR]

The problem of observation error in assessing the dynamics of populations over time has received increasing attention of late. Of particular interest has been a density- independent dynamic model, which allows a trend and is commonly employed in population viability analysis (PVA). Most of the recent work in this area has focused on assessing the impact of the observation error and on finding corrected estimators, primarily under normal models with the observation errors assumed to have a constant variance. This paper provides a comprehensive overview of statistical methods for this problem and evaluates them through simulations. This includes the development and assessment of simple and practical ways to obtain standard errors and confidence intervals for the basic parameters in the model and functions of them, such as the intrinsic rate of increase or the probability of eventual extinction. We allow for unequally spaced data and possibly changing observation error variances, and we also discuss how to employ standard errors that often accompany the estimated abundances. Both likelihood techniques under normality and methods allowing non-normal observation errors are discussed, and we describe how the various likelihood- based techniques can be implement using standard mixed-model software, such as PROC MIXED in SAS. The projection technique we use to handle functions of the basic parameters is also valuable when there is no observation error. The methods are motivated and illustrated using data for grizzly bears, Whooping Cranes, California Condors, and Puerto Rican Parrots. We present a simulation experiment to evaluate the performance of the some of the methods. [ABSTRACT FROM AUTHOR]

Data are often collected for a single species within an ecological community, so quantitative tools for drawing inferences about the unobserved portions of the community from single-species data are valuable. In this paper, we present and examine a method for estimating community dimension (the number of strongly interacting species or groups) from time series data on a single species. The dynamics of one species can be strongly affected by environmental stochasticity acting not only on itself, but also on other species with which it interacts. By fully accounting for the effects of stochasticity on populations embedded in a community, our approach gives better estimates of community dimension than commonly used methods. Using a combination of time series data and simulations, we show that failing to properly account for stochasticity when attempting to relate population dynamics to attributes of the community can give misleading information about community dimension. [ABSTRACT FROM AUTHOR]

This paper briefly presents the aims, requirements and results of partial least squares regression analysis (PLSR), and its potential utility in ecological studies. This statistical technique is particularly well suited to analyzing a large array of related predictor variables (i.e. not truly independent), with a sample size not large enough compared to the number of independent variables, and in cases in which an attempt is made to approach complex phenomena or syndromes that must be defined as a combination of several variables obtained independently. A simulation experiment is carried out to compare this technique with multiple regression (MR) and with a combination of principal component analysis and multiple regression (PCA+MR), varying the number of predictor variables and sample sizes. PLSR models explained a similar amount of variance to those results obtained by MR and PCA+MR. However, PLSR was more reliable than other techniques when identifying relevant variables and their magnitudes of influence, especially in cases of small sample size and low tolerance. Finally, we present one example of PLSR to illustrate its application and interpretation in ecology. [ABSTRACT FROM AUTHOR]

The paper is based on an on-going 3-year study in the wetland communities of Kampala. The study uses participatory methods and aims to contribute to (i) the development of low-income wetland communities, (ii) to prepare these communities to become less dependent on wetlands without receding into poverty, and (iii) the better management of the wetlands. The communities in direct dependence and intimate interaction with Nakivubo wetlands are mainly poor, live and work under hazardous conditions, and their activities pose a threat to the ecological function of the wetlands. Yet these wetlands are important for filtering the city’s waste and storm water before it flows into Lake Victoria’s Murchison Bay, which is Kampala’s source of piped water. Government approaches to the problem of wetland encroachment have largely failed because they are confrontational, and are not consistent or participatory. The study has in the first year conducted a series of activities including stakeholder analysis, resource analysis, livelihood analysis, a questionnaire survey and action planning. Preliminary data show that wetland dependency is very high among the poor nearby communities. They practice cultivation, brick-making and harvesting of wetland vegetation. However, these activities are under threat because wetland resources are dwindling due to increasing population and over-use. Livelihoods are threatened not only by the decreasing productivity of the wetland, but also by the ever-present government threat to evict wetland encroachers to restore its ecology. The study therefore works with communities to prepare for less dependence on wetlands so that they do not suddenly recede into worse poverty if they are evicted. They formulate strategies to enhance alternative livelihood, and for management of the wetland. Action plans have been formulated to address the situation through a newly created association. [ABSTRACT FROM AUTHOR]

Motivation: The Buell-Small Succession Study (BSS) is the longest running study of post agricultural succession in North America. To honor this program, a symposium at the Ecological Society of America meetings was organized to explore the state of succession theory and its contribution to the field of ecology and its application to restoration. The BSS was originally motivated by two controversies in the literature during the 1950's. The first was between a community versus and individual basis of secondary succession. The second was the validity of the Initial Floristic Composition hypothesis. Location: Hutcheson Memorial Forest, Somerset, New Jersey, USA Methods: Vegetation composition and cover has been continuously quantified in permanent plots established in 10 old fields. Continued Research Motivation: The rich data set has documented population and community dynamics and the spatio-temporal controls and historical contingencies that influence those dynamics. The regulation of community dynamics continues to be a line of inquiry as does the application of results to restoration and understanding the dynamics of non-native species. Conclusions: Long term vegetation studies are uncommon in ecology yet they are uniquely valuable for understanding system dynamics - particularly if the studies capture periodic events or system shifts such as droughts and invasions by non-native species. Resilient long term studies, of which the BSS is an example, maintain methods and data structure while allowing motivating questions to evolve along side advancements in the theoretical and conceptual realms of the field. Succession continues to serve as a basic tenet of ecology which is demonstrated by the papers making up this special issue. [ABSTRACT FROM AUTHOR]

The need to improve environmental management in Australia is urgent because human health, well-being and social stability all depend ultimately on maintenance of life-supporting ecological processes. Ecological science can inform this effort, but when issues are socially and economically complex the inclination is to wait for science to provide answers before acting. Increasingly, managers and policy-makers will be called on to use the present state of scientific knowledge to supply reasonable inferences for action based on imperfect knowledge. Hence, one challenge is to use existing ecological knowledge more effectively; a second is to tackle the critical unanswered ecological questions. This paper identifies areas of environmental management that are profoundly hindered by an inability of science to answer basic questions, in contrast to those areas where knowledge is not the major barrier to policy development and management. Of the 22 big questions identified herein, more than half are directly related to climate change. Several of the questions concern our limited understanding of the dynamics of marine systems. There is enough information already available to develop effective policy and management to address several significant ecological issues. We urge ecologists to make better use of existing knowledge in dialogue with policy-makers and land managers. Because the challenges are enormous, ecologists will increasingly be engaging a wide range of other disciplines to help identify pathways towards a sustainable future. [ABSTRACT FROM AUTHOR]

The identification of spatial structures is a key step in understanding the ecological processes structuring the distribution of organisms. Spatial patterns in species distributions result from a combination of several processes occuring at different scales: identifying these scales is thus a crucial issue. Recent studies have proposed a new family of spatial predictors (PCNM: principal coordinates of neighbours matrices; MEMs: Moran's eigenvectors maps) that allow for modelling of spatial variation on different scales. To assess the multi-scale spatial patterns in multivariate data, these variables are often used as predictors in constrained ordination methods. However, the selection of the appropriate spatial predictors is still troublesome, and the identification of the main scales of spatial variation remains an open question. This paper presents a new statistical tool to tackle this issue: the multi-scale pattern analysis (MSPA). This ordination method uses MEMs to decompose ecological variability into several spatial scales and then summarizes this decomposition using graphical representations. A canonical form of MSPA can also be used to assess the spatial scales of the species-environment relationships. MSPA is compared to constrained ordination using simulated data, and illustrated using the famous oribatid mites dataset. The method is implemented in the free software R. [ABSTRACT FROM AUTHOR]

Bayesian statistical modeling has several benefits within an ecological context. In particular, when observed data are limited in sample size or representativeness, then the Bayesian framework provides a mechanism to combine observed data with other "'prior" information. Prior information may be obtained from earlier studies, or in their absence, from expert knowledge. This use of the Bayesian framework reflects the scientific "learning cycle." where prior or initial estimates are updated when new data become available. In this paper we outline a framework for statistical design of expert elicitation processes for quantifying such expert knowledge, in a form suitable for input as prior information into Bayesian models. We identify six key elements: determining the purpose and motivation for using prior information; specifying the relevant expert knowledge available: formulating the statistical model; designing effective and efficient numerical encoding; managing uncertainty; and designing a practiced elicitation protocol. We demonstrate this framework applies to a variety of situations, with two examples from the ecological literature and three from our experience. Analysis of these examples reveals several recurring important issues affecting practical design of elicitation in ecological problems. [ABSTRACT FROM AUTHOR]

Despite the wide variation in the structural characteristics in natural forests, tree size distribution show fundamental similarities that suggest general underlying principles. The metabolic ecology theory predicts the number of individual scales as the −2 power of tree diameter. The demographic equilibrium theory predicts tree size distribution starting from the relationship of size distributions with growth and mortality at demographic equilibrium. Several analytic predictions for tree size distributions are derived from the demographic equilibrium theory, based on different growth and mortality functions. In addition, some purely phenomenological functions, such as polynomial function, have been used to describe the tree size distributions. In this paper, we use the metabolic ecology theory, the demographic equilibrium theory and the polynomial function to predict the tree size distribution for both the whole community and each species in an old-growth temperate forest in northeastern China. The results show that metabolic ecology theory predictions for the scaling of tree abundance with diameter were unequivocally rejected in the studied forest. Although these predictions of demographic theory are the best models for most of the species in the temperate forest, the best models for some species ( Tilia amurensis, Quercus mongolica and Fraxinus mandshurica) are compound curves (i.e. rotated sigmoid curves), best predicted by the polynomial function. Hence, the size distributions of natural forests were unlikely to be invariant and the predictive ability of general models was limited. As a result, developing a more sophisticated theory to predict tree size distributions remains a complex, yet tantalizing, challenge. [ABSTRACT FROM AUTHOR]

The area-and-isolation paradigm, which has been the primary focus of metapopulation research, may not hold in some animal metapopulations if within-patch preference is more important than patch area or connectivity. Recently, regression analyses have been used to evaluate the effect of patch connectivity and various patch qualities including area. However, their relative importance is not easy to determine, because patch qualities and connectivity are often spatially autocorrelated. In this paper, we try to evaluate the relative importance of within-patch quality, patch connectivity and spatial autocorrelation using variation partitioning methods from community ecology. We constructed three regression models: within-patch quality, PCNM (principal coordinates of neighbor matrices) and patch connectivity based on a one-season survey of a damselfly Copera annulata metapopulation. The contribution of within-patch quality was larger than that of connectivity. There was no prominent effect of patch area. We conclude that the area-and-isolation paradigm is not applicable to this C. annulata metapopulation. The spatial autocorrelation extracted by PCNM had the largest contribution; it contained almost all of the variation of connectivity and overlapped with variation explained by within-patch quality. Connectivity corresponded most closely to medium-scale spatial structure captured by PCNM (ca 640 m). The mean effective dispersal scale was estimated to be 53 m. Within-patch quality, debris accumulation and vegetation cover in the pond corresponded with the medium and small (ca 201 m) spatial scales from PCNM, though we could not clearly explain the cause of this correspondence. We believe that our method will contribute to quick and effective evaluation of spatial and non-spatial aspects of metapopulation. [ABSTRACT FROM AUTHOR]

Functional ecology aims at determining the relationships between species traits and environmental variables in order to better understand biological processes in ecosystems. From a methodological point of view, this biological objective calls for a method linking three data matrix tables: a table L with abundance or presence-absence values for species at a series of sites, a table R with variables describing the environmental conditions of the sites, and a table Q containing traits (e.g., morphological or behavioral attributes) of the species. Ten years ago, the fourth-corner method was proposed to measure and test the relationships between species traits and environmental variables using tables R, L, and Q simultaneously. In practice, this method is rarely used. The major reasons for this lack of interest are the restriction of the original method and program to presence-absence data in L and to the analysis of a single trait and a single environmental variable at a time. Moreover, ecologists often have problems in choosing a permutation model among the four originally proposed. In this paper, we revisit the fourth-corner method and propose improvements to the original approach. First, we present an extension to measure the link between species traits and environmental variables when the ecological community is described by abundance data. A new multivariate fourth-corner statistic is also proposed. Then, using numerical simulations, we discuss and evaluate the existing testing procedures. A new two-step testing procedure is presented. We hope that these elements will help ecologists use the best possible methodology to analyze this type of ecological problem. [ABSTRACT FROM AUTHOR]

Animal geography, emphasising jointly ‘actant’ behaviour of animals and people, encourages an innovative rethink of animal ecology, including animal strategies, hopes and fears in foraging, in a co-dependent framework with human behaviour. This paper studies bird–human reactions and feeding interactions in Peterborough, Ontario. It uses ecological survey methods, and also relies on alternative sources, including unique bird behaviours and ‘strategies’, intra-species differences and human emotions, preferences and feeding strategies. Feeders’ presence attracted birds to non-habitat areas, altering the ecology of avian presence and foraging, and preferential feeding created serious, previously non-existent, inter-species conflicts and inventive, usually successful reactions from birds. There were inter-species, and in some cases intra-species, hierarchies of dominance, based on possible avian decisionmaking co-dependent with the human behaviours in the continually recreated and inflected spaces. This possibly anthropomorphic perspective of bird behaviour moves beyond established theories of adaptation and the relation of human–bird behavioural interactions to bird ecology. [ABSTRACT FROM AUTHOR]

I hypothesized that statistical ritual has supplanted knowledge accrual as the sine qua non of wildlife science. Under the hypothesis, I deduced occurrence of 1) significance testing of the obvious and inconsequential, 2) quantitative debasement of research problems, and 3) publication of papers that largely lacked information but were methodologically impeccable. Articles in past and recent wildlife literature fit the deductions and supported the hypothesis. Thus, wildlife science is operating inefficiently because quantitative formalities are supplanting ecological information in technical articles. This problem can be corrected by a change of mindset in authors, referees, and editors. The change entails less emphasis on quantitative ritual and more emphasis on information that aids in understanding and explaining nature and managing wildlife. [ABSTRACT FROM AUTHOR]

The North Atlantic intertidal community provides a rich set of organismal and environmental material for the study of ecological genetics. Clearly defined environmental gradients exist at multiple spatial scales: there are broad latitudinal trends in temperature, meso-scale changes in salinity along estuaries, and smaller scale gradients in desiccation and temperature spanning the intertidal range. The geology and geography of the American and European coasts provide natural replication of these gradients, allowing for population genetic analyses of parallel adaptation to environmental stress and heterogeneity. Statistical methods have been developed that provide genomic neutrality tests of population differentiation and aid in the process of candidate gene identification. In this paper, we review studies of marine organisms that illustrate associations between an environmental gradient and specific genetic markers. Such highly differentiated markers become candidate genes for adaptation to the environmental factors in question, but the functional significance of genetic variants must be comprehensively evaluated. We present a set of predictions about locus-specific selection across latitudinal, estuarine, and intertidal gradients that are likely to exist in the North Atlantic. We further present new data and analyses that support and contradict these simple selection models. Some taxa show pronounced clinal variation at certain loci against a background of mild clinal variation at many loci. These cases illustrate the procedures necessary for distinguishing selection driven by internal genomic vs. external environmental factors. We suggest that the North Atlantic intertidal community provides a model system for identifying genes that matter in ecology due to the clarity of the environmental stresses and an extensive experimental literature on ecological function. While these organisms are typically poor genetic and genomic models, advances in comparative genomics have provided access to molecular tools that can now be applied to taxa with well-defined ecologies. As many of the organisms we discuss have tight physiological limits driven by climatic factors, this synthesis of molecular population genetics with marine ecology could provide a sensitive means of assessing evolutionary responses to climate change. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are common tools for assessing the potential impact of climate change on species ranges. Uncertainty in SDM output occurs due to differences among alternate models, species characteristics and scenarios of future climate. While considerable effort is being devoted to identifying and quantifying the first two sources of variation, a greater understanding of climate scenarios and how they affect SDM output is also needed. Climate models are complex tools: variability occurs among alternate simulations, and no single ‘best’ model exists. The selection of climate scenarios for impacts assessments should not be undertaken arbitrarily - strengths and weakness of different climate models should be considered. In this paper, we provide bioclimatic modellers with an overview of emissions scenarios and climate models, discuss uncertainty surrounding projections of future climate and suggest steps that can be taken to reduce and communicate climate scenario-related uncertainty in assessments of future species responses to climate change. [ABSTRACT FROM AUTHOR]

Ecological fitting is the process whereby organisms colonize and persist in novel environments, use novel resources or form novel associations with other species as a result of the suites of traits that they carry at the time they encounter the novel condition. This paper has four major aims. First, we review the original concept of ecological fitting and relate it to the concept of exaptation and current ideas on the positive role of phenotypic plasticity in evolution. Second, we propose phenotypic plasticity, correlated trait evolution and phylogenetic conservatism as specific mechanisms behind ecological fitting. Third, we attempt to operationalize the concept of ecological fitting by providing explicit definitions for terms. From these definitions, we propose a simple conceptual model of ecological fitting. Using this model, we demonstrate the differences and similarities between ecological fitting and ecological resource tracking and illustrate the process in the context of species colonizing new areas and forming novel associations with other species. Finally, we discuss how ecological fitting can be both a precursor to evolutionary diversity or maintainer of evolutionary stasis, depending on conditions. We conclude that ecological fitting is an important concept for understanding topics ranging from the assembly of ecological communities and species associations, to biological invasions, to the evolution of biodiversity. [ABSTRACT FROM AUTHOR]

Aim Nowadays, large amounts of species distribution data and software for implementing different species distribution modelling methods are freely available through the internet. As a result, methodological works that analyse the relative performance of modelling techniques, as well as those that study which species characteristics affect their performance, are necessary. We discuss three important topics that must be kept in mind when modelling species distributions, namely (i) the distinction between potential and realized distribution, (ii) the effect of the relative occurrence area of the species on the results of the evaluation of model performance, and (iii) the general inaccuracy of the predictions of the realized distribution provided by species distribution modelling methods. Location Unspecific. Methods Using some recent papers as a basis, we illustrate the three issues mentioned above and discuss the negative implications of neglecting them. Results Considering a potential-realized distribution gradient, different modelling methods may be arranged along this gradient according to their ability to model any concept. Complex techniques may be more suitable to model the realized distribution than simple ones, which may be more appropriate to estimate the potential distribution. Comparisons among techniques must consider this scenario. The relative occurrence area of the species conditions the results of the evaluation scores, implying that models of rare species will unavoidably yield higher discrimination values. Moreover, discrimination values that are usually reported in the literature may imply considerable over or underestimations of the distribution of the species. Main conclusions It is extremely important to establish a solid conceptual and methodological framework on which the emergent field of species distribution modelling can stand and develop. [ABSTRACT FROM AUTHOR]

1. The major aim of this paper was to explore the mechanistic basis of induced defensive ant response in myrmecophytic Piper species and their ant-partner Pheidole bicornis by combining experimental trials and chemical analysis. 2. In field experiments, the response of Pheidole ants to simulated stem-damage of their host plant was documented. Their reaction to other myrmecophytic and non-myrmecophytic Piper species was explored by fixing respective stem sections onto inhabited Piper fimbriulatum individuals. After artificial damage to stems of P. fimbriulatum and stem sections from other myrmecophytic Piper, the number of ants increased to a maximum of 63 individuals on the damaged internode within the first 10 min. By contrast, no or only a poor reaction was elicited by stem sections from the selected non-myrmecophytic Piper species. 3. Solid-phase microextraction/gas chromatography–mass spectrometry identified 68 volatile organic compounds (VOCs) which were emitted from wounded stem bark of three myrmecophytic ( P. fimbriulatum, P. obliquum, P. sagittifolium) and two non-myrmecophytic ( P. hispidum, P. riparense) Piper species, comprising monoterpenes, sesquiterpenes, simple aromatic compounds, and green leaf volatiles (GLVs, oxylipins). Despite considerable variation in the VOC profiles, an analysis of similarities (anosim) classified the accumulation of the sesquiterpenes β-caryophyllene, germacrene D and emission of the oxylipin reactive electrophilic species (RES) compounds hexanal, cis-3-hexene-1-ol, 2-hexenal, 2-undecanone and 1-hexanol as characteristic of the myrmecophytic species. 4. Synthesis. Field experiments showed that mechanical disturbance of myrmecophytic Piper stems is not sufficient to elicit recruitment and alertness of the ant-partner Ph. bicornis, but that specific volatiles released from the host plant are responsible. Analyses of the VOCs identified after simulated stem damage of three myrmecophytic and two non-myrmecophytic Piper species revealed differences in their VOC emission profiles: Only in the myrmecophytic species were induced stress compounds found, such as various oxylipin RES or the sesquiterpene β-caryophyllene, which are typically emitted after plant damage for interplant signalling. Some of these compounds (e.g. hexanal, 1-hexanol) are known to induce alerting and alarm behaviours in several ant species. Our study provides evidence that the VOCs of the Piper host plant may signal stem damage and induce recruitment and alert behaviour of associated Pheidole ants. [ABSTRACT FROM AUTHOR]

This paper proposes a new way of using forward selection of explanatory variables in regression or canonical redundancy analysis. The classical forward selection method presents two problems: a highly inflated Type I error and an overestimation of the amount of explained variance. Correcting these problems will greatly improve the performance of this very useful method in ecological modeling. To prevent the first problem, we propose a two-step procedure. First, a global test using all explanatory variables is carried out. If, and only if, the global test is significant, one can proceed with forward selection. To prevent overestimation of the explained variance, the forward selection has to be carried out with two stopping criteria: (1) the usual alpha significance level and (2) the adjusted coefficient of multiple determination (Ra²) calculated using all explanatory variables. When forward selection identifies a variable that brings one or the other criterion over the fixed threshold, that variable is rejected, and the procedure is stopped. This improved method is validated by simulations involving univariate and multivariate response data. An ecological example is presented using data from the Bryce Canyon National Park, Utah, USA. [ABSTRACT FROM AUTHOR]

Aim Models of the potential distributions of invading species have to deal with a number of issues. The key one is the high likelihood that the absence of an invading species in an area is a false absence because it may not have invaded that area yet, or that it may not have been detected. This paper develops an approach for screening pseudo-absences in a way that is logical and defensible. Innovation The step-wise approach involves: (1) screening environmental variables to identify those most likely to indicate conditions where the species cannot invade; (2) identifying and selecting the most likely limiting variables; (3) using these to define the limits of its invasion potential; and (4) selecting points outside these limits as true absence records for input into species distribution models. This approach was adopted and used for the study of three prominent Hakea species in South Africa. Models with and without the false absence records were compared. Two rainfall variables and the mean minimum temperature of the coldest month were the strongest predictors of potential distributions. Models which excluded false absences predicted that more of the potential distribution would have a high invasion potential than those which included them. Main conclusions The approach of applying a priori knowledge can be useful in refining the potential distribution of a species by excluding pseudo-absence records which are likely to be due to the species not having invaded an area yet or being undetected. The differences between the potential distributions predicted by the different models convey more information than making a single prediction, albeit a consensus model. The robustness of this approach depends strongly on an adequate knowledge of the ecology, invasion history and current distribution of that species. [ABSTRACT FROM AUTHOR]

The SE-SZ-8 site of Nanggu is a large Lapita site in the Reef/Santa Cruz group of the Southeast Solomon Islands. This paper provides a detailed discussion of its geomorphological and environmental context on Santa Cruz and the within site position of four marine shell dates from it, followed by a Bayesian analysis of the radiocarbon dating of the site. The analysis includes two new marine shell dates on additional species to overcome possible problems due to species selected for dating. Together these data indicate that despite recent critique of the sequence of the three excavated decorated Lapita sites (SE-SZ-8, SE-RF-2, SE-RF-6) proposed by Green (1991a) for the Reef/Santa Cruz Group there is little basis to suggest the Nanggu site is not both the oldest dated Lapita site in the sequence, but also earlier than any other so far identified within the period of early Lapita colonization of Remote Oceania. [ABSTRACT FROM AUTHOR]

Understanding how disturbance shapes the dynamics of ecological systems is of fundamental importance in ecology. One emerging approach to revealing and appreciating disturbance effects involves examining disturbance-driven changes in the variability of ecological responses. Variability is rarely employed as a response variable to assess the influence of disturbance, but recent studies indicate that it can be an extremely sensitive metric, capturing differences obscured by averaging and conveying important ecological information about underlying causal processes. In this paper, we present a conceptual model to understand and predict the effects of disturbance on variability. The model estimates qualitative changes in variability by considering disturbance extent, frequency and intensity, as well as ecosystem recovery, and thereby captures not only the immediate effects of disturbance but also those that arise over time due to the biotic response to an event. We evaluate how well the model performs by comparing predictions with empirical results from studies examining a wide variety of disturbances and ecosystems, and discuss factors that may modify or even confound predictions. We include a concise guide to characterizing and detecting changes in variability, highlighting the most common and easily applied methods and conclude by describing several future directions for research. By considering variability as a response to disturbance, we gain another metric of fundamental system behaviour, an improved ability to identify organizing features of ecosystems and a better understanding of the predictability of disturbance-driven change – all critical aspects of assessing ecosystem response to disturbance. [ABSTRACT FROM AUTHOR]

The South American Cerrado is the largest tropical savanna of the world, and one of the most threatened biomes on the Earth. Levels of bird endemism in this biome are controversial, but the most up-to-date study points to 30 endemic species. In this paper, I analysed the recent range shift by one of those species, the curl-crested jay Cyanocorax cristatellus, comparing it with three other alleged Cerrado endemics (lesser nothura Nothura minor, chestnut-capped foliage-gleaner Hylocryptus rectirostris, and grey-backed tachuri Polystictus superciliaris) and a ‘near-endemic’ (white-banded tanager Neothraupis fasciata). The curl-crested jay expanded its range considerably into south-eastern Brazil during the last century, colonizing extensive areas formerly covered by the Atlantic forest, which has been almost completely cleared by human activity. I found no evidence of recent range shift for the four other species studied, but demonstrated that the grey-backed tachuri is not a Cerrado endemic. I found that the vegetation map used by previous authors to classify birds as endemics is imprecise and out-of-date, not depicting well the biome limits, resulting in an arbitrary, sometimes erroneous, classification. I suggested the adoption of a more modern and detailed Cerrado map. The necessity of a comprehensive review in the list of Cerrado's endemic birds in light of modern vegetation maps is highlighted. [ABSTRACT FROM AUTHOR]

Several boreal insect species respond to smoke and heat generated by forest fires and use recent burns to reproduce in high numbers. Some of these species are rare or uncommon in undisturbed forests, and the contribution of recently burned habitats to their population dynamics has been deemed crucial by some to their long-term persistence. Consequently, the severe decline seen in some species in Fennoscandia has been frequently linked with fire suppression. In this paper, we explore some aspects of the spatial dynamics of pyrophilous insect populations in relation to the expected relative contribution of burned and unburned habitats to their global population dynamics. Forest fires are, throughout the boreal forest biome, generally highly aggregated in some years while rare in most other years. The low connectivity between fire events and the typical life cycle seen in these species make it improbable that recent burns act as significant population sources. This leads us to suggest that populations of pyrophilous species may be more limited by the adequacy of the unburned matrix than by the occurrence of fire events. Moreover, by combining an age-class distribution model and a dead wood availability model, we show that the quality of the unburned matrix increases in landscapes with longer fire cycles, in which pyrophilous insects should persist at higher population levels. We conclude that the degradation of the unburned habitat better explains the decline of pyrophilous insects than fire suppression alone. [ABSTRACT FROM AUTHOR]

1. A growing body of literature suggests that some plants may engage in a game of Tragedy of the Commons when competing for soil resources. Two annual plants sharing a whole space will produce more roots per individual and less reproductive yield per individual than one plant with half the space to itself. 2. Several papers have recently suggested that the increase in soil volume in going from a single plant to two competitor plants (as has been the case in empirical tests of the above prediction) may produce the increased root proliferation independent of the competitor. 3. We extend the Tragedy of the Commons model of Gersani et al. (2001 ) to explicitly consider the separate effects of volume per plant ( V) and nutrient concentration per unit volume ( N) on root proliferation and yield of plants that ‘own’ their space relative to plants that share their space with a competitor. We then use simulations resulting from the model to evaluate existing data and the new perspectives provided by recent challenges to the conceptual basis for the Tragedy of the Commons. 4. When N is held constant, increasing V should produce an almost linear increase in root proliferation and net nutrient profit for reproduction. The increase in roots should be more pronounced for two plants sharing their space, and the increase in yield should be more pronounced for plants with exclusive access to half the space. When V ¥  N is held constant, roots per plant should at first increase and then decline with increased volume. The difference between a plant that ‘owns’ its space vs. one that shares its space with a competitor should be less pronounced as V increases. 5. Synthesis. We use this model to help clarify some confusion surrounding the Tragedy of the Commons theory of below-ground competition by showing how issues raised by others are not incompatible with the approach used to generate the Tragedy of the Commons theory and highlight future opportunities for research on root growth strategies. [ABSTRACT FROM AUTHOR]

In exploring the relationship between multivariate abundance data and environmental variables, a rarely used approach is to graph raw data separately for each different taxon. It is proposed that such raw data graphs become part of the standard toolset for graphing and analysing multivariate abundances. The key advantage of this approach is that axis scales have quantitative interpretations, enabling quantitative interpretation of patterns in abundance. In contrast, ordinations only present qualitative information. Ordinations are useful for inferring overall, qualitative patterns and raw data graphing is a complementary tool of greater use for answering more specific questions, aimed at a deeper understanding the ecology of a community. It is demonstrated using some well-known examples that our understanding of the nature of associations can be considerably improved by using raw data graphs, even when only plotting a subset of variables. One example describes how an often-cited dataset has been misinterpreted in key methodological papers, because data were interpreted from ordinations alone, with no consideration of plots of the raw data. [ABSTRACT FROM AUTHOR]

Successful conservation plans are not solely achieved by acquiring optimally designed reserves. Ongoing monitoring and management of the biodiversity in those reserves is an equally important, but often neglected or poorly executed, part of the conservation process. In this paper we address one of the first and most important steps in designing a monitoring program – deciding what to monitor. We present a strategy for prioritizing species for monitoring and management in multispecies conservation plans. We use existing assessments of threatened status, and the degree and spatial and temporal extent of known threats to link the prioritization of species to the overarching goals and objectives of the conservation plan. We consider both broad and localized spatial scales to capture the regional conservation context and the practicalities of local management and monitoring constraints. Spatial scales that are commensurate with available data are selected. We demonstrate the utility of this strategy through application to a set of 85 plants and animals in an established multispecies conservation plan in San Diego County, California, USA. We use the prioritization to identify the most prominent risk factors and the habitats associated with the most threats to species. The protocol highlighted priorities that had not previously been identified and were not necessarily intuitive without systematic application of the criteria; many high-priority species have received no monitoring attention to date, and lower-priority species have. We recommend that in the absence of clear focal species, monitoring threats in highly impacted habitats may be a way to circumvent the need to monitor all the targeted species. [ABSTRACT FROM AUTHOR]

This paper puts forward the premise that fortifications are uniquely suited to addressing questions of climatic variation and human response, as they are large, permanent repositories of human history, and also reflect behaviors directly associated with conflict, tertitorialism, and the limits of local environments. A revision of theoretical perspectives and a model of conflict derived from human behavioral ecology can better direct future research. In application, this model outlines a program of research for fortifications, which can be used to more critically assess the impact of paleoclimatic change on human prehistory. [ABSTRACT FROM AUTHOR]

In the three decades since its introduction, resource selection analysis (RSA) has become a widespread method for analyzing spatial patterns of animal relocations obtained from telemetry studies. Recently, mechanistic home range models have been proposed as an alternative framework for studying patterns of animal space-use. In contrast to RSA models, mechanistic home range models are derived from underlying mechanistic descriptions of individual movement behavior and yield spatially explicit predictions for patterns of animal space-use. In addition, their mechanistic underpinning means that, unlike RSA, mechanistic home range models can also be used to predict changes in space-use following perturbation. In this paper, we develop a formal reconciliation between these two methods of home range analysis, showing how differences in the habitat preferences of individuals give rise to spatially explicit patterns of space-use. The resulting unified framework combines the simplicity of resource selection analysis with the spatially explicit and predictive capabilities of mechanistic home range models. [ABSTRACT FROM AUTHOR]