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Urbanisation constitutes one of the most rapid human-induced environmental changes, developing at the expense of natural and semi-natural habitats. It often implies alterations of many abiotic and biotic factors and contributes to create new environmental conditions, including temperature, food resources, competition and predation. Despite increasing empirical evidence of intra-specific divergence in phenotypic traits (e.g., physiological, behavioural or morphological) between urban and rural individuals, such patterns have often remained disconnected from the underlying mechanisms involved. In the current study, we tested for divergence in functional morphological traits that are related to feeding ecology (i.e., bill morphology, body mass and condition) and/or to the locomotory performance in escaping from predators (i.e., wing, tarsus and tail morphology, body mass and condition) along a chronological gradient of urbanisation (old urban, recent urban and rural areas), using the New Zealand fantail, an endemic insectivorous passerine species. We found divergences in phenotypic traits related to bill morphology along the urban–rural gradient: birds inhabiting the old urban area had stubbier bills (i.e., shorter, deeper and wider bills) than those inhabiting the recent urban and rural areas. We did not detect any difference in locomotion-related morphological traits. Our results suggest the urbanisation-induced alteration in food resources may drive morphological divergence in bird populations. We emphasized the need for mechanistic and experimental studies, with a particular focus on resource-based mechanisms, to identify more precisely the morphological responses of urban populations to changes in food composition, and the resulting implications for communities in urban ecosystems.

International audience; Context: Determining the appropriate scale at which to study species’ interactions with their environment is a great challenge.Objective: We investigated the spatial extent at which landscape structure affects the occurrence of four species of terrestrial mammalian herbivores in the Brazilian savannas and examined whether those scales could be explained by species ecological traits and how forest habitat was operationally defined.Methods: Using maps of forest cover, camera trapping and occupancy modelling, we determined the relations between three landscape metrics (percentage of forest cover, patch density and edge density) and the occurrence of four species. To determine the optimal scale of effect for each species, we computed landscape metrics at different spatial extents (from 0.5 to 10 km radius) from camera trap locations and for three forest maps, each using different operational definitions of a forest pixel: minimum of tree cover of 25, 50 or 75%.Results: The occupancy models revealed scales of effect of 0.5 to 2 km with the scale of effect being similar among three of the species. However, the probability of a scale of effect being detected depended upon how forest is operationally defined, being greater when forest was defined with greater tree cover, particularly for forest-specialist species.Conclusions: Besides biological traits, the way habitat is operationally defined shapes our ability to detect the scale of effects. Thus, it is necessary not to adopt a multi-scale approach, but also to use multiple operational definitions of habitat, considering particularities of how each species interact with their environment.

International audience; Modern human societies have negatively impacted native species richness and their adaptive capacity on every continent, in clearly contrasting ways. We propose a general model to explain how the sequence, duration, and type of colonising society alter native species richness patterns through changes in evolutionary pressures. These changes cause different 'filtering effects' on native species, while simultaneously altering the capacity of surviving species to adapt to further anthropogenic pressures. This framework may better explain the observed native species extinction rates and extirpation legacies following human colonisation events, as well as better predict future patterns of human impact on biodiversity.

Although the perils of plastics to living organisms including humans have been neglected for decades, they have recently been recognized as a major environmental problem worldwide. Little progress has been made on understanding the factors that drive species´ and populations´ susceptibilities to the ingestion of plastic. Here, we propose using nutritional ecology as a multidisciplinary framework for bridging the gaps that link nutrition, behavior, plastics, physiology and ecology. We show that nutritional niches are tightly linked to plastic ingestion, illustrating the application of our framework in the context of nutritional niche theory, habitat-specific foraging from species to populations, and transfer patterns in food webs. Fil: Machovsky-capuska, Gabriel. University of Sydney; Australia Fil: Amiot, Christophe. Université d’Angers; Francia Fil: Denuncio, Pablo Ezequiel. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Grainger, Richard. University of Sydney; Australia Fil: Raubenheimer, David. University of Sydney; Australia

International audience; Our understanding of the niche concept will remain limited while the quantity and range of different food types eaten remain a dominant proxy for niche breadth, as this does not account for the broad ecological context that governs diet. Linking nutrition, physiology and behaviour is critical to predict the extent to which a species adjusts its nutritional niche breadth at the levels of prey (“prey composition niche,” defined as the range of prey compositions eaten) and diet (“realized nutritional niche” is the range of diets composed through feeding on the prey).Here, we studied adult chick‐rearing Australasian gannets Morus serrator to propose an integrative approach using sea surface temperature anomalies (SSTa), geographic location and bathymetry over different years, to explore their relationship with the nutritional composition of prey and diets (i.e. prey composition and nutritional niche breadth), habitat use and foraging behaviour.We found that gannets feed on prey that varied widely in their nutritional composition (have a broad prey composition niche), and composed diets from these prey that likewise varied in composition (have a broad realized nutritional niche), suggesting generalism at two levels of macronutrient selection.Across seasons, we established “nutritional landscapes” (hereafter nutriscapes), linking the nutritional content of prey (wet mass protein‐to‐lipid ratio—P:L) to the most likely geographic area of capture and bathymetry. Nutriscapes varied in their P:L from 6.06 to 15.28, over time, space and bathymetry (0–150 m).During warm water events (strong positive SSTa), gannets expanded their foraging habitat, increased their foraging trip duration and consumed prey and diets with low macronutrient content (wet mass proportions of P and L). They were also constrained to the smallest prey composition and realized nutritional niche breadths.Our findings are consistent with previous suggestions that dietary generalism evolves in heterogeneous environments, and provide a framework for understanding the nutritional goals in wild marine predators and how these goals drive ecological interactions and are, in turn, ultimately shaped by environmental fluctuations.

International audience; Predators that forage on foods with temporally and spatially patchy distributions may rely on private or public sources of information to enhance their chances of foraging success. Using GPS tracking, field observations, and videography, we examined potential sites and mechanisms of information acquisition in departures for foraging trips by colonially breeding Australasian gannets (Morus serrator). Analyses of the bill-fencing ceremony between mated pairs of breeding gannets did not detect correlations between parameters of this reciprocal behavior and foraging trips, as would have been predicted if gannets used this behavior as a source of private information. Instead, 60 % of the departing birds flew directly to join water rafts of other conspecific en route to the feeding grounds. The departure of solitary birds from the water rafts was synchronized (within 60 s) with the arrival of incoming for-agers and also among departing birds. Furthermore, solitary departing birds from the rafts left in the same directional quadrant (908 slices) as the prior arriving (67 %) and also prior departing forager (79 %). When associated plunge dives of conspecific were visible from the colony, providing a public source of information, gannets more often departed from the water rafts in groups. Our study thus provides evidence for the use of water rafts, but not the nest site, as locations of information transfer, and also confirms the use of local enhancement as a strategy for foraging flights by Australasian gannets.

Translocation of endangered species to habitats where exotic predators have been removed is now a common conservation practice around the world. Many of these translocated populations have thrived, and they are often used as sources for the harvesting of individuals for translocations to sites where exotic predators still exist, albeit at reduced densities. This study investigates how isolation from exotic predators affects the ability of individuals to recognize such predators using the North Island robin (Petroica longipes) as a model. The study was carried out in three robin populations in the North Island, New Zealand: a translocated population on Tiritiri Matangi Island, where exotic mammalian predators are absent; a population reintroduced from Tiritiri Matangi Island to Wenderholm Regional Park, a mainland site where these mammals are controlled to low densities; and a mainland population at Benneydale where exotic predatory mammals are common. The response intensity of robins to a model stoat was high at Benneydale and low at Tiritiri Matangi and Wenderholm. This result indicates that isolation from mammalian predators on Tiritiri Matangi has suppressed the ability of North Island robins to recognize these predators. It is possible that the low predatory mammal densities at Wenderholm have reduced robin contact with stoats, therefore reduced the opportunity for robins to learn to recognize stoats. Thus, translocation of individuals from populations without predators to places where key predators still exist could be unsuccessful if translocated individuals fail to perform appropriate anti-predator behaviours.

New environmental conditions may impact on behaviour and morphology, and consequently affect population dynamics. Rapid response to new conditions is likely to be a key factor in species introduction success. The Red-whiskered Bulbul Pycnonotus jocosus is an Asian species which, following accidental introduction only 30 years ago, has colonized the two climatically and ecologically contrasting sides of the island of Reunion in the Indian Ocean. We assessed the degree of morphological divergence of mature birds in 11 nonseasonal and three seasonal characters, in windward and leeward sites. Our study showed (1) that sexual dimorphism existed, (2) that when sexual dimorphism is controlled, nine non-seasonal characters differed significantly between windward and leeward sites, (3) that these non-seasonal characters define groups of geographically proximal sites, especially in males, and (4) that classification according to the most indicative character, the bill, also clearly separated birds from windward and leeward sites. These results indicate very rapid morphological divergence, particularly in bill size, in an introduced bird species in fewer than ten generations. We suggest that differences in diet could partly explain this variability.

International audience; Knowledge about the maturity status of specimens included in evolutionary, tax-onomic or life history investigations is fundamentally important. This study investigated the use of the degree of cranial suture fusion, the developmental status of cranial bones, and the degree of tooth wear as indicators for cranial maturity status in Delphinus sp. from New Zealand waters. In total, 15 sutures, one joint and three nonmetric characters were assessed on 66 skulls obtained from stranded and by-caught individuals sampled between 1932 and 2011. A suture index (SI) was computed based on 10 sutures, in which degree of fusion was correlated with age and the three misclassification indices (MI), calculated for a given suture, were

The steam room in medieval french châteaux and palaces, by jean Mesqui. The private steam rooms in medieval châteaux and palaces constituted a luxury reserved for a minority of princes and great lords, essentially from the 1340 onwards. A synthesis concerning these little known installations is proposed on the basis of an inventory of preserved examples., Les chambres d'étuve privées dans les châteaux et palais du Moyen Age constituent un luxe réservé à une minorité de princes et de grands seigneurs, essentiellement à partir des années 1340. Un inventaire des exemplaires conservés à ce jour permet de proposer une synthèse de ces aménagements encore peu connus., Mesqui Jean, Amiot Christophe, Bon Philippe, Brodeur Jean, Carru Dominique, Chevet Pierre, Faucherre Nicolas, Marchant Sylvie. L'étuve dans les châteaux et palais du Moyen Âge en France. In: Bulletin Monumental, tome 159, n°1, année 2001. Les Bains privés au Moyen âge et à la Renaissance. pp. 7-20.

International audience; Vocalisations are important for territorial defence, mate attraction, and species recognition in many songbirds. Comparative studies on the songs of birds between islands and mainland populations provide insight into the evolution of vocal communication in terms of both ecological and social factors. We compared the vocalisations of tui (Prosthemadera novaeseelandiae novaeseelandiae), an endemic honeyeater from New Zealand's mainland, with those of a subspecies from the remote Chatham Islands (P. n. chathamensis). Song spectral variables of male long-range 'broadcasting' songs differed between mainland and Chatham Island tui populations. Songs recorded from five mainland populations had significantly greater syllable diversity and produced a higher percentage of trills than those from the Chatham Islands. These characteristics have been revealed in past studies as being sexually selected traits positively correlated with male genetic diversity. The acoustic adaptation hypothesis could also help to elucidate the presence of a significantly higher percentage of trill components in the songs of the mainland population, as the mainland study sites in general contained more areas of open vegetation, where trills transmit more effectively than in dense forest, which dominated the sampling sites on the Chatham Islands. Future research into the variation of tui song complexity in relation to population size, geographic isolation, and habitat structure between different mainland sites would provide further insight into links between selective pressures and vocal complexity.

International audience; Human-leopard conflict exists throughout the distribution range of leopards. The management of such interactions with humans is a high priority for the Nepalese authorities. To gain information on the extent of the human-leopard conflict in the region, we collected carnivore scat over an area of approximately 400 km2 in the lower belt of the Annapurna Conservation Area, Nepal. We used species-specific polymerase chain reaction techniques to verify the identity of the scat and identified the diet using micro-histological analysis. Out of 83 scats, 36 were positively identified using molecular analysis as originating from common leopards and 47 were leopard-negative. Wild prey contributed more than 82% of the common leopard diet, with the barking deer comprising most of this (33.5%). Domestic livestock was ranked second, at 17% of the diet. Other carnivores consumed small mammals (rodents, 27%) and livestock (19%), the proportion of which was higher than that consumed by common leopards in this region, although this difference was not significant. Our results suggest that small carnivores are no less responsible than common leopards for livestock depredation in the study area.

Amiot Christophe. 11. Les étuves du château de Montmuran (Ille-et-Villaine, commune Les Iffs) . In: Bulletin Monumental, tome 159, n°1, année 2001. Les Bains privés au Moyen âge et à la Renaissance. pp. 52-54.

Amiot Christophe. 14. L'appartement des bains du château de Vitré (Ille-et-Villaine) . In: Bulletin Monumental, tome 159, n°1, année 2001. Les Bains privés au Moyen âge et à la Renaissance. pp. 59-61.

Amiot Christophe. 13. Les étuves du château de Suscinio (Morbihan, commune de Sarzeau) . In: Bulletin Monumental, tome 159, n°1, année 2001. Les Bains privés au Moyen âge et à la Renaissance. pp. 57-58.

Amiot Christophe. 6. Les étuves du manoir de Coadélan (Côtes-d'Armor, commune de Prat). In: Bulletin Monumental, tome 159, n°1, année 2001. Les Bains privés au Moyen âge et à la Renaissance. pp. 38-40.