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The caloric content and macronutrient ratio of diet consumed is a major source of phenotypic variation in most animal populations. While these nutritional effects have been well-documented for a variety of life-history and morphological traits, the effects of nutrition on male genitals are poorly understood but genitals are thought to be more canalised than general morphology and hence less susceptible to variation in nutrition. Even less is known about the effects of nutrition on female genital form, which to our knowledge, have never been investigated. Here we tested for effects of juvenile dietary macronutrients (protein and carbohydrate) on larval survival, adult morphology, including genital size and shape in male and female flour beetles (Tribolium castaneum). We found there was nutritionally induced plasticity in larval survival and morphology, although the latter effect was variable, with body size being most responsive to dietary macronutrients and genital size and shape being least responsive. Functionally equivalent morphological traits in the sexes responded similarly to nutrition. Previously, we showed that the genitalia of male and female T. castaneum are subject to strong stabilising sexual selection, and our current findings suggest that developmental mechanisms reduce the nutritional sensitivity of male and female genitals, possibly to ensure matching during mating. [ABSTRACT FROM AUTHOR]

This article presents the case of the Beirut River corridor in Lebanon, which defines the administrative border between the capital Beirut, its eastern and south-eastern suburbs. The Beirut River has undergone several transformations from being a lotic environment to becoming complex urban infrastructure. This is often unnoticeable due to the scarcity of its running water and its walled existence at the edge of administrative boundaries. The separation from its riverbanks, disconnection from the urban fabric, and continuous pollution have contributed to its liminality, being simultaneously neither present nor absent. To understand this in-betweenness, the river’s spatial, temporal, and social liminality are analysed by identifying major events, actors, and key urban planning interventions that impacted the river at the national, city region, and local scales. The article explores the development of the river corridor both in terms of urbanisation and population dynamics; its distinct positionality in different periods that corresponded to major events and decisions made; and the contrasting river experiences and perceptions across generations, which vary between reminiscence and aversion. By examining the various transformative processes, collective practices, perceptions, and diverse actors, the article highlights the contextual implications of this obdurate liminality, but also Beirut River’s potential alternative future positionality amidst present and imminent urban challenges.

Copyright of Orientation Scolaire et Professionnelle (OSP) is the property of Institut National d'Etude du Travail et d'Orientation Professionnelle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

How do the same mechanisms that faithfully regenerate complex developmental programmes in spite of environmental and genetic perturbations also allow responsiveness to environmental signals, adaptation and genetic evolution? Using the nematode Caenorhabditis elegans as a model, we explore the phenotypic space of growth and development in various genetic and environmental contexts. Our data are growth curves and developmental parameters obtained by automated microscopy. Using these, we show that among the traits that make up the developmental space, correlations within a particular context are predictive of correlations among different contexts. Furthermore, we find that the developmental variability of this animal can be captured on a relatively low‐dimensional phenotypic manifold and that on this manifold, genetic and environmental contributions to plasticity can be deconvolved independently. Our perspective offers a new way of understanding the relationship between robustness and flexibility in complex systems, suggesting that projection and concentration of dimension can naturally align these forces as complementary rather than competing. Synopsis: The fundamental principles that govern the emergence of robustness and flexibility in complex biological systems are explored by studying the structure of variability in the development of Caenorhabditis elegans in response to genetic and diet perturbations.Correlations in traits within populations of isogenic individuals in a single environment are predictive of correlations between populations that differ in genetic background or environment.Dimensionality reduction can yield representations of development that can separate genetic perturbations from environmental ones, and, among genetic perturbations, natural genetic variations from single gene mutations.These observations can be understood in the context of a projection operator‐based model for the generation and expression of phenotypic variability. [ABSTRACT FROM AUTHOR]

L’entrepreneuriat est un des sujets qui polarise l’attention des gens de tout bord : politiciens, enseignants, chômeurs, employés, etc. s’y intéressent. Pris sous l’angle d’une discipline scientifique, beaucoup de recherches en entrepreneuriat ont été produites en RDC. A cet effet, le présent article cherche à faire le mariage entre certaines recherches produites dans le domaine de l’entrepreneuriat avec les trois paradigmes les plus en vue en entrepreneuriat.

Abstract How do the same mechanisms that faithfully regenerate complex developmental programmes in spite of environmental and genetic perturbations also allow responsiveness to environmental signals, adaptation and genetic evolution? Using the nematode Caenorhabditis elegans as a model, we explore the phenotypic space of growth and development in various genetic and environmental contexts. Our data are growth curves and developmental parameters obtained by automated microscopy. Using these, we show that among the traits that make up the developmental space, correlations within a particular context are predictive of correlations among different contexts. Furthermore, we find that the developmental variability of this animal can be captured on a relatively low‐dimensional phenotypic manifold and that on this manifold, genetic and environmental contributions to plasticity can be deconvolved independently. Our perspective offers a new way of understanding the relationship between robustness and flexibility in complex systems, suggesting that projection and concentration of dimension can naturally align these forces as complementary rather than competing.

Copyright of Nouveau Praticien Vétérinaire Élevages et Santé is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Triatomine control campaigns have traditionally consisted of spraying the inside of houses with pyrethroid insecticides. However, exposure to sublethal insecticide doses after the initial application is a common occurrence and may have phenotypic consequences for survivors. Here, using Triatoma infestans (the main vector of Chagas disease in the Southern Cone of South America) as a model species, we quantified the effects of exposure to a sublethal dose of pyrethroid insecticide on wing morphology. We tested if the treatment (i) induced a plastic effect (change in the character mean); (ii) altered environmental canalisation (higher individual variation within genotypes); (iii) altered genetic canalisation (higher variation among genotypes); and (iv) altered developmental stability (higher fluctuating asymmetry [FA]). Methods Each of 25 full-sib families known to be susceptible to pyrethroid insecticides were split in two groups: one to be treated with a sublethal dose of deltamethrin (insecticide-treated group) and the other to be treated with pure acetone (control group). Wings of the emerging adults were used in a landmark-based geometric morphometry analysis to extract size and shape measurements. Average differences among treatments were measured. Levels of variation among families, among individuals within families and among sides within individuals were computed and compared among treatments. Results Wing size and shape were affected by a sublethal dose of deltamethrin. The treated insects had larger wings and a more variable wing size and shape than control insects. For both wing size and shape, genetic variation was higher in treated individuals. Individual variations and variations in FA were also greater in deltamethrin-treated insects than in control ones for all full-sib families; however, the patterns of shape variation associated with genetic variation, individual variation and FA were different. Conclusions Insects exposed to a sublethal dose of deltamethrin presented larger, less symmetrical and less canalised wings. The insecticide treatment jointly impaired developmental stability and genetic and environmental canalisation. The divergent patterns of shape variation suggest that the related developmental buffering processes differed at least partially. The morphological modifications induced by a single sublethal exposure to pyrethroids early in life may impinge on subsequent flight performance and consequently affect the dynamics of house invasion and reinfestation, and the effectiveness of triatomine control operations. Graphical Abstract

There is substantial variation in language experience betweenlearners, yet there is surprising similarity in the languagestructure they eventually acquire. While it is possible that thiscanalisation of language structure may be due to constraintsimposed by modulators, such as an innate language system, itmay instead derive from the broader, communicativeenvironment in which language is acquired. In this paper, thelatter perspective is tested for its adequacy in explaining therobustness of language learning to environmental variation. Acomputational model of word learning from cross-situational,multimodal information was constructed and tested. Key tothe model’s robustness was the presence of multiple,individually unreliable information sources that could supportlearning when combined. This “degeneracy” in the languagesystem had a detrimental effect on learning when compared toa noise-free environment, but was critically important foracquiring a canalised system that is resistant to environmentalnoise in communication.

In nature, plants interact with multiple insect herbivores that may arrive simultaneously or sequentially. There is extensive knowledge on how plants defend themselves against single or dual attack. However, we lack information on how plants defend against the attack of multiple herbivores that arrive sequentially. In this study, we investigated whether Brassica nigra L. plants are able to defend themselves against caterpillars of the late-arriving herbivore Plutella xylostella L., when plants had been previously exposed to sequential attack by four other herbivores (P. xylostella, Athalia rosae, Myzus persicae and Brevicoryne brassicae). We manipulated the order of arrival and the history of attack by four herbivores to investigate which patterns in sequential herbivory determine resistance against the fifth attacker. We recorded that history of sequential herbivore attack differentially affected the capability of B. nigra plants to defend themselves against caterpillars of P. xylostella. Caterpillars gained less weight on plants attacked by a sequence of four episodes of attack by P. xylostella compared to performance on plants that were not previously damaged by herbivores. The number of times the plant was attacked by herbivores of the same feeding guild, the identity of the first attacker, the identity and the guild of the last attacker as well as the order of attackers within the sequence of multiple herbivores influenced the growth of the subsequent herbivory. In conclusion, this study shows that history of sequential attack is an important factor determining plant resistance to herbivores. [ABSTRACT FROM AUTHOR]

In its initial incarnation, island studies regarded islands as highly distinct entities that justified a relatively closed discipline. This orientation was first widened by address to issues such as the linkage of (pre-existent) islands to adjacent areas and, over the last decade, has been further modified by consideration of island-like areas. The latter has led to an increasing acknowledgement that, in some contexts, at least, islands form components of complex aquatic and terrestrial systems in which islandness is a less distinctive attribute than in the case of archetypal (usually marine) islands. While neglected by island studies, river systems that include islands, peninsulas and/or engineered waterfront developments are significant for problematising the distinctiveness of islands and thereby merit attention. This article sets out to map some of the complexities around islands and rivers with specific regard to the Richmond River in northern New South Wales, Australia. We profile this river since its lower reaches feature a range of natural and artificial island and island-like features, including the engineered area known as Ballina Island. We develop our study with regard to both Indigenous perceptions of the riverine space and disruptions, interventions and innovations resulting from European settlement in the region. As such, the article attempts to progress island studies' research on riverine environments, to problematise the notion of discrete islands/islandness in such contexts and to prompt greater disciplinary reflection on the issues arising from such scrutiny. [ABSTRACT FROM AUTHOR]

Background: Triatomine control campaigns have traditionally consisted of spraying the inside of houses with pyrethroid insecticides. However, exposure to sublethal insecticide doses after the initial application is a common occurrence and may have phenotypic consequences for survivors. Here, using Triatoma infestans (the main vector of Chagas disease in the Southern Cone of South America) as a model species, we quantified the effects of exposure to a sublethal dose of pyrethroid insecticide on wing morphology. We tested if the treatment (i) induced a plastic effect (change in the character mean); (ii) altered environmental canalisation (higher individual variation within genotypes); (iii) altered genetic canalisation (higher variation among genotypes); and (iv) altered developmental stability (higher fluctuating asymmetry [FA]). Methods: Each of 25 full-sib families known to be susceptible to pyrethroid insecticides were split in two groups: one to be treated with a sublethal dose of deltamethrin (insecticide-treated group) and the other to be treated with pure acetone (control group). Wings of the emerging adults were used in a landmark-based geometric morphometry analysis to extract size and shape measurements. Average differences among treatments were measured. Levels of variation among families, among individuals within families and among sides within individuals were computed and compared among treatments. Results: Wing size and shape were affected by a sublethal dose of deltamethrin. The treated insects had larger wings and a more variable wing size and shape than control insects. For both wing size and shape, genetic variation was higher in treated individuals. Individual variations and variations in FA were also greater in deltamethrin-treated insects than in control ones for all full-sib families; however, the patterns of shape variation associated with genetic variation, individual variation and FA were different. Conclusions: Insects exposed to a sublethal dose of deltamethrin presented larger, less symmetrical and less canalised wings. The insecticide treatment jointly impaired developmental stability and genetic and environmental canalisation. The divergent patterns of shape variation suggest that the related developmental buffering processes differed at least partially. The morphological modifications induced by a single sublethal exposure to pyrethroids early in life may impinge on subsequent flight performance and consequently affect the dynamics of house invasion and reinfestation, and the effectiveness of triatomine control operations. [ABSTRACT FROM AUTHOR]

Biological systems are commonly constituted by a high number of interacting agents. This great dimensionality hinders biological modelling due to the high computational cost. Therefore, new modelling methods are needed to reduce computation time while preserving the properties of the depicted systems. At this point, Boolean Networks have been revealed as a modelling tool with high expressiveness and reduced computing times. The aim of this work has been to introduce an automatic and coherent procedure to model systems through Boolean Networks. A synergy that harnesses the strengths of both approaches is obtained by combining an existing approach to managing information from biological pathways with the so-called Nested Canalising Boolean Functions (NCBF). In order to show the power of the developed method, two examples of an application with systems studied in the bibliography are provided: The epithelial-mesenchymal transition and the lac operon. Due to the fact that this method relies on directed graphs as a primary representation of the systems, its applications exceed life sciences into areas such as traffic management or machine learning, in which these graphs are the main expression of the systems handled.

The objective of this work was to study the changes that, selecting for environmental variability of birth weight (BW), could bring to other interesting traits in livestock such as: survivability at weaning (SW), litter size (LS) and weaning weight (WW), their variability assessed from standard deviations of LS, standard deviation of WW (SDWW) and also the total litter weight at birth (TLBW) and total litter weight at weaning. Data were registered after eight generations of a divergent selection experiment for BW environmental variability in mice. Genetic parameters and phenotypic and genetic evolution were assessed using linear homoscedastic and heteroscedastic models in which the traits were attributed to the female, except BW and WW that were in some models also attributed to the pup. Genetic correlation between the trait and variability levels was −0.81 for LS and −0.33 for WW. Clear divergent phenotypic trends were observed between lines for LS, WW and SDWW. Although animals were heavier in the high line, TLBW and at weaning was greater in the low line. Despite the negative genetic correlation that was obtained, SDWW was also higher in the high line. Heritabilities were 0.21 and 0.06, respectively, for LS and SW. Both phenotypic and genetic trends showed clear superiority of the low line over the high line for these traits, but inferior for WW. Heteroscedastic model performed similar to the homoscedastic model when there was enough information. Considering LS and survival, the low line was preferred from a welfare point of view, but its superiority from the productivity perspective was not clear. Robustness seemed higher as shown by a low variation and having a benefit to the animal welfare, but this still remains unclear. It was concluded that low variation benefits the welfare of animals.

Abstract: Fresh waters are increasingly threatened by flow modification. Knowledge about the impacts of flow modification is incomplete, especially in the tropics where ecological studies are only starting to emerge in recent years. Using presence/absence data dated approximately four decades apart (~1966 to ~2010) from 10 tropical rivers, we assessed the changes in freshwater fish assemblage and food web after flow modification. The sites were surveyed with methods best suited to habitat conditions (e.g., tray/push netting for low‐order forest streams, visual surveys for canalised rivers and net casting for impounded rivers). With the presence/absence data, we derived and compared six measures of fish assemblage and food web structure: species richness, proportion of native species, overall functional diversity, native functional diversity, food web complexity and maximum trophic level. We found that changes in community assemblage and food web structure were not generalisable across modification regimes. In canalised sites, species richness and maximum trophic levels were lower in the second time period while the opposite was true for impounded sites. However, proportion of native species was consistently lower in the second time period across modification regimes. Changes in fish assemblages and food webs appear to be driven by species turnover. We recorded 79 cases of site‐specific extirpation and 117 cases of site‐specific establishment. Our data further suggest that turnover in assemblage is again contingent on flow‐modification regime. While the process was stochastic in canalised rivers, benthopelagic species were more likely to be extirpated from impounded rivers where species lost were replaced by predominantly alien fish taxa. [ABSTRACT FROM AUTHOR]

L’évaluation de la pertinence des mesures d’atténuations proposées par une étude d’impacts lors d’un projet d’aménagement s’effectue par la mise en place de veilles écologiques. Néanmoins, ce type de suivis est rare puisqu’aucune législation ne l’impose. Focus sur la plaine de Crau où une veille écologique a été mise en place afin d’évaluer les mesures compensatoires et les mesures d’atténuations proposées par une étude d’impact lors de l’enfouissement de canalisations sur un écosystème sensible.

L’évaluation de la pertinence des mesures d’atténuations proposées par une étude d’impacts lors d’un projet d’aménagement s’effectue par la mise en place de veilles écologiques. Néanmoins, ce type de suivis est rare puisqu’aucune législation ne l’impose. Focus sur la plaine de Crau où une veille écologique a été mise en place afin d’évaluer les mesures compensatoires et les mesures d’atténuations proposées par une étude d’impact lors de l’enfouissement de canalisations sur un écosystème sensible.

Abstract Data from an experimental mice population selected from 18 generations to increase weight gain were used to estimate the genetic parameters associated with environmental variability. The analysis involved three traits: weight at 21 days, weight at 42 days and weight gain between 21 and 42 days. A dataset of 5273 records for males was studied. Data were analysed using Bayesian procedures by comparing the Deviance Information Criterion (DIC) value of two different models: one assuming homogeneous environmental variances and another assuming them as heterogeneous. The model assuming heterogeneity was better in all cases and also showed higher additive genetic variances and lower common environmental variances. The heterogeneity of residual variance was associated with systematic and additive genetic effects thus making reduction by selection possible. Genetic correlations between the additive genetic effects on mean and environmental variance of the traits analysed were always negative, ranging from -0.19 to -0.38. An increase in the heritability of the traits was found when considering the genetic determination of the environmental variability. A suggested correlated canalised response was found in terms of coefficient of variation but it could be insufficient to compensate for the scale effect associated with an increase of the mean.

Abstract The aim of this research was to explore the genetic parameters associated with environmental variability for litter size (LS), litter weight (LW) and mean individual birth weight (IW) in mice before canalisation. The analyses were conducted on an experimental mice population designed to reduce environmental variability for LS. The analysed database included 1976 records for LW and IW and 4129 records for LS. The total number of individuals included in the analysed pedigree was 3997. Heritabilities estimated for the traits under an initial exploratory approach varied from 0.099 to 0.101 for LS, from 0.112 to 0.148 for LW and from 0.028 to 0.033 for IW. The means of the posterior distribution of the heritability under a Bayesian approach were the following: 0.10 (LS), 0.13 (LW) and 0.03 (IW). In general, the heritabilities estimated under the initial exploratory approach for the environmental variability of the analysed traits were low. Genetic correlations estimated between the trait and its variability reached values of -0.929 (LS), -0.815 (LW) and 0.969 (IW). The results presented here for the first time in mice may suggest a genetic basis for variability of the evaluated traits, thus opening the possibility to be implemented in selection schemes.

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the primary ways that organisms cope with environmental change is through regulation of the hypothalamo-pituitary-adrenal ( HPA) axis, the neuroendocrine system that controls reactions to stress. Variation in genes regulating the HPA axis - particularly the glucocorticoid receptor - may facilitate adaptation to changing climatic conditions by altering expression. Here we examine signatures of selection on the glucocorticoid receptor gene ( Nr3c1) in African starlings that inhabit a range of environments, including those with variable climatic conditions. To investigate potential adaptive mechanisms underlying the vertebrate stress response, we sequence the Nr3c1 gene in 27 species of African starlings. Although we find some evidence of positive selection, substitution rate is negatively correlated with variance in precipitation. This suggests climatic cycling in sub-Saharan Africa may have resulted in lower substitution rates to maintain a successful coping strategy. When environmental conditions fluctuate rapidly, variation in the strength of purifying selection can explain evolutionary rate variation. [ABSTRACT FROM AUTHOR]

Winglessness in the two-spot ladybird beetle Adalia bipunctata (L.) is determined by a single locus with the wingless allele recessive to the winged wildtype allele. The expression of the wingless trait is highly variable, with individuals missing a variable part of elytra and flight wings; the elytra and wings appear to be truncated rather than miniature in form. The degree of winglessness is partly determined genetically. Here we report on the phenotypic plasticity of the degree of winglessness. The environmental effect on elytron length relative to maximal elytron length in wingless phenotypes was studied by rearing offspring of single pair crosses of this form at a low (19°C) or high (29°C) temperature. Offspring reared at 19°C showed relatively longer elytra than those reared at 29°C.

Genes and environment make the organism. Darwin stood firm in his denial of any direct role of environment in the modification of heredity. His theory of evolution heralded two debates: one about the importance and adequacy of natural selection as the main mechanism of evolution, and the other about the role of genes versus environment in the modification of phenotype and evolution. Here, I provide an overview of the second debate and show that the reasons for the gene versus environment battle were twofold: first, there was confusion about the role of environment in modifying the inheritance of a trait versus the evolution of that trait, and second, there was misunderstanding about the meaning of environment and its interaction with genes in the production of phenotypes. It took nearly a century to see that environment does not directly affect the inheritance of a phenotype (i.e., its heredity), but it is nevertheless the primary mover of phenotypic evolution. Effects of genes and environment are not separate but interdependent. One cannot separate the effect of genes from that of environment, or nature from nurture. To answer the question posed in the title, it is partly because the 20th century has been a century of unending progress in genetics. But also because unlike physics, biology is not colorblind; progress in biology has often been delayed beyond the Kuhnian paradigm change due to built-in interest in negating the influence of environment. Those who are against evolution, of course, cannot be expected to understand the role of environment in evolution. Those for it, many biologists included, believing in the supremacy of genes empowers them by giving adaptation a solely gene-directed (self-driven) 'teleological' interpretation. [ABSTRACT FROM AUTHOR]

Copyright of Genome is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Kiel Canal (built between 1886 and 1895) connects the North Sea and the Baltic for seagoing vessels, yet, being 100 km long, about 10 m deep and 100 m wide, it also divides a landscape. This finding is the starting point for analysing the effects of infrastructure that facilitates communication and exchange but also produces obstructions and rivalries. This article explores the ambiguous effects this piece of infrastructure had on politics, technology, labour, trade and military strategy. The 'deep ditch' also had severe environmental consequences that were palpable until well into the twentieth century. By considering both the 'positive' and the 'negative' of the waterway, the narrative of 'connect-and-divide' avoids the still-too-often told affirmative story of transport infrastructure. Instead, it and opens the outlook to a multi-faceted history of transport infrastructures. [ABSTRACT FROM AUTHOR]

Over the past several decades, it has become increasingly apparent that much of our cognitive abilities rely on the existence of innate theories of some specific domain of knowledge. For example, it seems that children possess an innate basis of information about other minds whose disruption can ensue in pathological states like autism. Innate beliefs have also been invoked in the explanation of other domains of cognitive competence such as: our knowledge of basic properties of physical objects and of kinds of stuff; children's ability at exploiting limited information about numbers, sets, and basic algebraic operations; adults' conception of numbers; music perception; naïve conceptions of the physical world; certain facial expressions of emotions; deductive inferences and our reasoning concerning actions and their practical consequences. But, what does it mean for something to be innate? The purpose of this paper is primarily to explore what constitutes innateness and how something is determined to be innate in light of the wide spectrum of positions developed under the ubiquitous umbrella of innateness. [ABSTRACT FROM AUTHOR]

Abstract: There have been few mechanistic studies linking local ecological characteristics of streams to morphological pressures. This paper reports the findings of an investigation of the impacts of canalisation on salmonid habitat. Habitat use by Atlantic salmon and brown trout, fry and parr was assessed using Generalised Additive Models (GAMs) based on seasonal electrofishing survey data and output from 2-dimensional hydraulic models. By overlaying the habitat models onto the physical characteristics of the canalised reach, it was possible to determine where and when environmental bottlenecks occurred, and for which species and life stages. The canalised reach was characterised by relatively uniform sedimentary and hydraulic characteristics compared to other reaches. Although it was generally well suited to fry, the lack of coarser substrate and low velocity areas during winter made the canalised reach unfavourable for salmon and trout parr respectively. Given the insights provided by this study, we suggest the approach of combining physical channel characterisation with locally derived seasonal habitat models is well suited to future research focussed on assessing the ecological impact of morphological pressures. [Copyright &y& Elsevier]