159 research outputs found

    Farmland bird assemblages exhibit higher functional and phylogenetic diversity than forest assemblages in France

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    Aim: Under a global change scenario, research focused on changes in assembly patterns over spatial and temporal axes is more than timely as it will improve our understanding about how biological communities respond to anthropogenic disturbance. Despite an increasing need to assess whether associations among diversity and community metrics change in relation to environmental heterogeneity, the way in which community assembly rules vary across habitats has been hardly explored. Here, we tested for differences in patterns of functional diversity (FD) and phylogenetic diversity (PD) between farmland and forest bird communities. Taxon: 107 species of breeding common birds. Location: continental France. Methods: We used an extensive dataset (13 years; 7,115 bird communities) from the French Breeding Bird survey in conjunction with a matrix of 142 functional traits (including information on habitat, diet, life-stories, behaviour, and morphology) to compute different metrics of FD and PD. Results: We found that farmland assemblages showed higher FD and PD than forest assemblages, which were phylogenetically clustered. Both FD and PD of forest assemblages increased with increasing species richness, whereas in farmland assemblages the relationship turned out to be asymptotic in both cases. It may be due to the accumulation of generalists, which can end up displacing specialist species when the environment becomes oversaturated triggering a decline in diversity. Contrary to expectations, FD and PD of farmland assemblages increased over the study period, whereas forest assemblages showed a non-linear pattern. Farmland and forest assemblages also showed divergent trajectories over time in relation to FD metrics. Main conclusions: We conclude that, although farmland intensification has led to a sharp decline in population of farmland birds, agriculture landscapes in Southern Europe still harbor diversity-rich communities probably due to the legacy effects of past land-use (traditional practices). Our study highlights the need to take into account the influence of historic landscape configurations when assessing the effect that contemporary land uses have on biotic communities. info:eu-repo/semantics/publishedVersio

    Discordant patterns of genetic and phenotypic differentiation in five grasshopper species codistributed across a microreserve network

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    Conservation plans can be greatly improved when information on the evolutionary and demographic consequences of habitat fragmentation is available for several codistributed species. Here, we study spatial patterns of phenotypic and genetic variation among five grasshopper species that are codistributed across a network of microreserves but show remarkable differences in dispersal-related morphology (body size and wing length), degree of habitat specialization and extent of fragmentation of their respective habitats in the study region. In particular, we tested the hypothesis that species with preferences for highly fragmented microhabitats show stronger genetic and phenotypic structure than codistributed generalist taxa inhabiting a continuous matrix of suitable habitat. We also hypothesized a higher resemblance of spatial patterns of genetic and phenotypic variability among species that have experienced a higher degree of habitat fragmentation due to their more similar responses to the parallel large-scale destruction of their natural habitats. In partial agreement with our first hypothesis, we found that genetic structure, but not phenotypic differentiation, was higher in species linked to highly fragmented habitats. We did not find support for congruent patterns of phenotypic and genetic variability among any studied species, indicating that they show idiosyncratic evolutionary trajectories and distinctive demographic responses to habitat fragmentation across a common landscape. This suggests that conservation practices in networks of protected areas require detailed ecological and evolutionary information on target species to focus management efforts on those taxa that are more sensitive to the effects of habitat fragmentation.JO was supported by a Ramón y Cajal Fellowship (RYC-2013-12501) and a research contract funded by Severo Ochoa Program (SEV-2012-0262). VGN is supported by a Forschungskredit of the University of Zurich (FK-14-103). VN is supported by a FPI predoctoral fellowship from Ministerio de Economía y Competitividad. This work received financial support from grants CGL2011-25053 (Ministerio de Economía y Competitividad), PCI08-0130-3954 and POII10-0197-0167 (Junta de Comunidades de Castilla-La Mancha and European Social Fund) and UNCM08-1E-018 (European Regional Development Fund).Peer reviewe

    Trophic niche shifts and phenotypic trait evolution are largely decoupled in Australasian parrots

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    Background: Trophic shifts from one dietary niche to another have played major roles in reshaping the evolutionary trajectories of a wide range of vertebrate groups, yet their consequences for morphological disparity and species diversity differ among groups. Methods: Here, we use phylogenetic comparative methods to examine whether the evolution of nectarivory and other trophic shifts have driven predictable evolutionary pathways in Australasian psittaculid parrots in terms of ecological traits such as body size, beak shape, and dispersal capacity. Results: We found no evidence for an ‘early-burst’ scenario of lineage or morphological diversification. The bestfitting models indicate that trait evolution in this group is characterized by abrupt phenotypic shifts (evolutionary jumps), with no sign of multiple phenotypic optima correlating with different trophic strategies. Thus, our results point to the existence of weak directional selection and suggest that lineages may be evolving randomly or slowly toward adaptive peaks they have not yet reached. Conclusions: This study adds to a growing body of evidence indicating that the relationship between avian morphology and feeding ecology may be more complex than usually assumed and highlights the importance of adding more flexible models to the macroevolutionary toolbox.info:eu-repo/semantics/publishedVersio

    Prey choice, provisioning behaviour, and effects of early nutrition on nestling phenotype of titmice

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    [EN] It is generally assumed that blue and great tits (Cyanistes caeruleus, Parus major) compete for the same type of food (Lepidoptera larvae) during the breeding season and that the former have some advantage because they are usually earlier and can exploit small caterpillars that are often more abundant and are not consumed by great tits. However, it is not clear whether, when confronted with similar circumstances (e.g., nestling demand), blue and great tits show similar preferences for a particular caterpillar type. In this 2-y study, we compare the diet of both tit species in detail by controlling for hatching date and brood size. We also examine how the contribution of caterpillars and spiders to the diet is related to nestling development. A positive relationship was found between the percentage of spiders in the diet and nestling tarsus length in both species, reinforcing the idea that neonatal nutrition could have a strong influence on nestling phenotype (e.g., offspring size). Such a correlation may arise because spiders contain a high level of taurine, an essential nutrient in the early development of young, and/or this prey type contains more calcium than other food items, which may affect the rate of nestling bone mineralization. Blue tits fed their young double the number of tortricid larvae in comparison with great tits, whereas the latter showed a clear preference for noctuids and exploited, with a low frequency, a type of larvae not consumed by blue tits, hairy caterpillars (Lasiocampidae). Our results point to resource partitioning by these species in this forest ecosystem and contribute to a better understanding of feeding ecology of titmice, which is particularly timely in a global warming context [FR] Il est généralement admis que les mésanges bleues (Cyanistes caeruleus) et les mésanges charbonnières (Parus major) se font compétition pour le même type de nourriture (larves de lépidoptères) durant la période de reproduction. Il est également admis que les mésanges bleues possèdent un certain avantage, car elles se reproduisent plus tôt et mangent de petites chenilles souvent plus abondantes qui ne sont pas consommées par les mésanges charbonnières. Cependant, il n'est pas clair si dans les mêmes conditions (ex. de demande en nourriture des oisillons), les mésanges bleues et charbonnières préfèrent les mêmes types de chenilles. Dans cette étude de 2 ans, nous avons comparé en détail les régimes alimentaires des 2 espèces de mésanges en contrôlant pour la date de ponte et la taille de la couvée. Nous avons aussi examiné si les contributions des chenilles et des araignées au régime alimentaire étaient reliées au développement des oisillons. Chez les 2 espèces, une relation positive a été trouvée entre le pourcentage d'araignées dans le régime alimentaire et la longueur du tarse des oisillons renforçant ainsi l'idée que la nutrition néonatale peut avoir une grande influence sur le phénotype des oisillons (ex. la taille des jeunes). Une telle corrélation peut résulter du fait que les araignées ont un taux élevé de taurine, un nutriment essentiel au développement précoce des jeunes, et/ou que ce type de proie contient plus de calcium que d'autres aliments ce qui peut influencer le taux de minéralisation des os chez les oisillons. Les mésanges bleues ont nourri leurs jeunes avec deux fois plus de larves de tortricidés que les mésanges charbonnières qui elles ont montré une nette préférence pour les noctuidés. Ces dernières ont aussi consommé, quoique peu fréquemment, des livrées (Lasiocampidae), un type de larves boudé par les mésanges bleues. Nos résultats pointent vers une division des ressources entre ces espèces dans cet écosystème forestier et contribuent à une meilleure compréhension de l'écologie alimentaire des mésanges ce qui est particulièrement utile dans un contexte de réchauffement climatiqueV. García-Navas was supported by a FPI predoctoral fellowship (Spanish Ministry of Science and Innovation (MICINN)-European Social Fund). This study was financed by the MICINN (grant reference: GCL2007-61395)Peer Reviewe

    Armeria maritima (Mill.) Willd. Flower hydromethanolic extract for Cucurbitaceae fungal diseases control

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    The cliff rose (Armeria maritima), like other halophytes, has a phenolics-based antioxidant system that allows it to grow in saline habitats. Provided that antioxidant properties are usually accompanied by antimicrobial activity, in this study we investigated the phytochemicals present in a hydromethanolic extract of A. maritima flowers and explored its antifungal potential. The main phytocompounds, identified by gas chromatography–mass spectrometry, were: hexadecanoic acid, octadecanoic acid, 9-octadecenoic acid, 3-(3,4-dihydroxy-phenyl)-acrylic acid ethyl ester, and benzeneacetaldehyde. The antifungal activity of the extract and its main constituents—alone and in combination with chitosan oligomers—was tested against six pathogenic taxa associated with soil-borne diseases of plant hosts in the family Cucurbitaceae: Fusarium equiseti, F. oxysporum f. sp. niveum, Macrophomina phaseolina, Neocosmospora falciformis, N. keratoplastica, and Sclerotinia sclerotiorum. In in vitro tests, EC90 effective concentrations in the 166−865 μg·mL−1 range were obtained for the chitosan oligomers–A. maritima extract conjugate complexes, lower than those obtained for fosetyl-Al and azoxystrobin synthetic fungicides tested for comparison purposes, and even outperforming mancozeb against F. equiseti. In ex situ tests against S. sclerotiorum conducted on artificially inoculated cucumber slices, full protection was achieved at a dose of 250 μg·mL−1. Thus, the reported results support the valorization of A. maritima as a source of biorationals for Cucurbitaceae pathogens protection, suitable for both organic and conventional agriculture

    Agricultural extensification enhances functional diversity but not phylogenetic diversity in Mediterranean olive groves: A case study with ant and bird communities

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    Agroforests are of well-known importance for biodiversity conservation, especially in the tropics, because they are structurally stable and may resemble natural forests. Previous studies have characterized jointly taxonomic, functional and phylogenetic diversity in these agro-ecosystems to comprehensively examine the mechanisms by which agriculture impacts on biodiversity. However, this approach has been barely applied to other woody crops of economic importance, such as olive grove, which is a remarkable overwintering habitat for frugivorous/insectivorous birds from central and northern Europe, and whose original distribution overlaps with the Mediterranean biodiversity hotspot. We examined the effects of landscape complexity and intensive management practices at a local scale (recurrent plowing and pesticides use) on the functional and phylogenetic diversity of animal communities inhabiting olive groves. Since the response of functional traits or clades may vary across different taxonomic groups, we conducted our study at two levels: ants, which are considered semi-sessile organisms, and birds, which exhibit a high dispersal capacity. In birds, neither management type nor landscape complexity had an effect on phylogenetic diversity (PD) indices. Extensively managed farms harbored bird communities with higher values of functional diversity (FD), but this effect only was evident when considering cultivated (productive) zones within the farm (i.e., infield diversity). Ant assemblages on intensively managed farms exhibited a lower level of phylogenetic clustering than those located in extensive farms, but this effect vanished when excluding non-cultivated zones. Ant functional diversity increased with landscape complexity. Our results indicate that PD and FD exhibit different responses to farming intensification in olive groves. Although intensive management does not erode PD due to the existence of phylogenetic redundancy, the loss of species associated to modern farming leads to a reduction in FD being this indicative of functional complementarity. This study provides evidence that land-use extensification (extensive farming and landscape diversification) promotes more functionally rich assemblages than modern intensive practices in olive groves. Our findings also show the need to set apart the effect of non-cultivated zones (e.g., hedgerows, margins) when evaluating the effectiveness of agri-environment schemes as the joint consideration of non-cultivated and cultivated areas may obscure the benefits of local extensification on infield biodiversity.info:eu-repo/semantics/publishedVersio

    Calorie restriction rescues mitochondrial dysfunction in Adck2-Deficient skeletal muscle

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    ADCK2 haploinsufficiency-mediated mitochondrial coenzyme Q deficiency in skeletal muscle causes mitochondrial myopathy associated with defects in beta-oxidation of fatty acids, aged-matched metabolic reprogramming, and defective physical performance. Calorie restriction has proven to increase lifespan and delay the onset of chronic diseases associated to aging. To study the possible treatment by food deprivation, heterozygous Adck2 knockout mice were fed under 40% calorie restriction (CR) and the phenotype was followed for 7 months. The overall glucose and fatty acids metabolism in muscle was restored in mutant mice to WT levels after CR. CR modulated the skeletal muscle metabolic profile of mutant mice, partially rescuing the profile of WT animals. The analysis of mitochondria isolated from skeletal muscle demonstrated that CR increased both CoQ levels and oxygen consumption rate (OCR) based on both glucose and fatty acids substrates, along with mitochondrial mass. The elevated aerobic metabolism fits with an increase of type IIa fibers, and a reduction of type IIx in mutant muscles, reaching WT levels. To further explore the effect of CR over muscle stem cells, satellite cells were isolated and induced to differentiate in culture media containing serum from animals in either ad libitum or CR diets for 72 h. Mutant cells showed slower differentiation alongside with decreased oxygen consumption. In vitro differentiation of mutant cells was increased under CR serum reaching levels of WT isolated cells, recovering respiration measured by OCR and partially beta-oxidation of fatty acids. The overall increase of skeletal muscle bioenergetics following CR intervention is paralleled with a physical activity improvement, with some increases in two and four limbs strength tests, and weights strength test. Running wheel activity was also partially improved in mutant mice under CR. These results demonstrate that CR intervention, which has been shown to improve age-associated physical and metabolic decline in WT mice, also recovers the defective aerobic metabolism and differentiation of skeletal muscle in mice caused by ADCK2 haploinsufficiency.This work was supported by Junta de Andalucía grant BIO-177, the Instituto de Salud Carlos III FIS grant FIS PI20/00541, CIBERER (U729)-ISCIII, the FEDER Funding Program from the European Union and the Spanish Ministry of Science, Innovation and Universities grant RED2018-102576-T. This work was supported by the Spanish Ministry of Education, Culture and Sports through fellowship FPU16/03264 to JH-C, and the Association Française contre les Myopathies (AFM) through fellowship grant #22450 to CV-G. This work was funded in part by the Intramural Research Program of the National Institute on Aging, NIH. This research was also supported by the Instituto de Salud Carlos III (PI19/01310) (Co-funded by the European Union) and by the Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) (2017: SGR 1428) and the CERCA
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