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Morphology can be adaptive through its effect on performance of an organism. The effect of performance may, however, be modulated by behavior; an organism may choose a behavioral option that does not fully utilize its maximum performance. Behavior may therefore be decoupled from morphology and performance. To gain insight into the relationships between these levels of organization, we combined morphological data on defensive structures with measures of defensive performance, and their utilization in defensive behavior. Scorpion species show significant variation in the morphology and performance of their main defensive structures; their chelae (pincers) and the metasoma ("tail") carrying the stinger. Our data show that size-corrected pinch force varies to almost two orders of magnitude among species, and is correlated with chela morphology. Chela and metasoma morphology are also correlated to the LD50 of the venom, corroborating the anecdotal rule that dangerously venomous scorpions can be recognized by their chelae and metasoma. Analyses of phylogenetic independent contrasts show that correlations between several aspects of chela and metasoma morphology, performance and behavior are present. These correlations suggest co-evolution of behavior with morphology and performance. Path analysis found a performance variable (pinch force) to partially mediate the relationship between morphology (chela aspect ratio) and behavior (defensive stinger usage). We also found a correlation between two aspects of morphology: pincer finger length correlates with the relative "thickness" (aspect ratio) of the metasoma. This suggests scorpions show a trade-off between their two main weapon complexes: the metasoma carrying the stinger, and the pedipalps carrying the chelae.

Human beings have been credited with unparalleled capabilities for digital prehension grasping. However, grasping behaviour is widespread among tetrapods. The propensity to grasp, and the anatomical characteristics that underlie it, appear in all of the major groups of tetrapods with the possible exception of terrestrial turtles. Although some features are synapomorphic to the tetrapod clade, such as well-defined digits and digital musculature, other features, such as opposable digits and tendon configurations, appear to have evolved independently in many lineages. Here we examine the incidence, functional morphology, and evolution of grasping across four major tetrapod clades. Our review suggests that the ability to grasp with the manus and pes is considerably more widespread, and ecologically and evolutionarily important, than previously thought. The morphological bases and ecological factors that govern grasping abilities may differ among tetrapods, yet the selective forces shaping them are likely similar. We suggest that further investigation into grasping form and function within and among these clades may expose a greater role for grasping ability in the evolutionary success of many tetrapod lineages. Fil: Sustaita, Diego. University Of Connecticut; Estados Unidos Fil: Pouydebat, Emmanuelle. Centre National de la Recherche Scientifique; Francia. Museum National d'Histoire Naturelle; Francia Fil: Manzano, Adriana Silvina. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Abdala, Virginia Sara Luz. Fundación Miguel Lillo. Dirección de Zoología. Instituto de Herpetología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hertel, Fritz. California State University; Estados Unidos Fil: Herrel, Anthony. Centre National de la Recherche Scientifique; Francia. Museum National d'Histoire Naturelle; Francia

International audience; 1. One of the main drivers of the genesis and maintenance of biodiversity is mobility, i.e. the net result of the interaction between physiological performances (movement capacity) and behavioural decisions (movement decisions). Although several previous studies have found personality traits related to mobility, it is not yet clear whether mobility involves a real syndrome, i.e. whether individuals showing good movement capacity are also more likely to decide to move, and whether these inter-individual differences are consistent across time. 2. The aim of the present study was therefore to disentangle the mechanisms underlying the maintenance of inter-individual variation in mobility by measuring three traits related to mobility under experimental conditions in a butterfly species, and to test the existence of correlations between these traits. These measures implied movement capacity and movement decision. 3. It was shown that mobility-related traits were (i) consistent across time, (ii) inter-correlated, and (iii) dependent upon sex and morphology. 4. These results therefore suggest the existence of a mobility syndrome in a butterfly. Such findings highlight the necessity to accurately integrate inter-individual variation (behavioural syndrome) in our comprehension of the evolution of movement strategies.

Grasping is essential for primates in numerous behaviors. A variety of different grasping techniques are used for obtaining food. Among humans, several studies have shown that the properties of the objects such as the size or the form influence grasp patterns. In addition, other works have tested the individual variability through grasping strategies and age and several studies have revealed some similarities between great apes and humans in grip types. Finally, results on hand preference are still equivocal and, for non-human primates, object parameters and age effect are rarely tested together, even though it is a methodological aspect important to consider. The study sought to determine whether grip type varied according to the age of the subject, the species (human versus chimpanzee), the size of the object and the hand used. Frame-by-frame analysis of hand contact strategies and statistical results indicated that (1) adults of both species used fewer contact strategies than juveniles and that there was a greater variability of contacts for small than for large objects (2) young juvenile chimpanzees and human children follow a similar grip types development, i.e. more frequent use of precision grips with age (3) juvenile chimpanzees used all five categories of grip and the adults used the "thumb-fingerpad(s)" more than the "precision grips" in addition to the "power grip" and (4) a right hand preference was greater for the grasping of small objects with "precision grips" in adults for both species. These results are discussed in relationship with neurology, morphology and grasping evolution.

International audience; Feeding behavior is known to be modulated as prey properties change. During prey capture, external prey properties, including size and mobility, are likely some of the most important components in predator–prey interactions. Whereas prey size has been demonstrated to elicit modulation of jaw movements during capture, how prey speed affects the approach and capture of prey remains unknown. We quantified the kinematics associated with movements of both the feeding and locomotor systems during prey capture in a lizard, Gerrhosaurus major, while facing prey differing in size and mobility (newborn mice, grasshoppers, and mealworms). Our data show that the feeding and locomotor systems were recruited differently in response to changes in the size or speed of the prey. The timing of jaw movements and of the positioning of the head are affected by changes in prey size—and speed, to a lesser extent. Changes in prey speed resulted in concomitant changes in the speed of strike and an early and greater elevation of the neck. External prey properties, and prey mobility in particular, are relevant in predator–prey interactions and elicit specific responses in different functional systems.

Phylogenetic comparative methods have long considered phylogenetic signal as a source of statistical bias in the correlative analysis of biological traits. However, the main life-history strategies existing in a set of taxa are often combinations of life history traits that are inherently phylogenetically structured. In this paper, we present a method for identifying evolutionary strategies from large sets of biological traits, using phylogeny as a source of meaningful historical and ecological information. Our methodology extends a multivariate method developed for the analysis of spatial patterns, and relies on finding combinations of traits that are phylogenetically autocorrelated. Using extensive simulations, we show that our method efficiently uncovers phylogenetic structures with respect to various tree topologies, and remains powerful in cases where a large majority of traits are not phylogenetically structured. Our methodology is illustrated using empirical data, and implemented in the adephylo package for the free software R.

International audience; Capsule Variation in prey availability appears to influence Chough fledging success and juvenile survival.Aims To determine seasonal and annual variations in Chough prey and how these influence and juvenile survival.Methods Chough faeces (n = 437, 3905 invertebrates) were collected year-round and analysed todetermine diet composition. Seasonal and annual variation in prey abundance in Chough foraging habitat was assessed using pitfall trapping (n = 747, 27 124 invertebrates) between 1996 and 2003.Fledging success was estimated for a population of 12 breeding pairs; juvenile survival was estimatedby year-round resighting (n < 2500) of individual birds that were colour-ringed as nestlings.Results- From April to June a high biomass of prey and a great variety of species were observed. Between July and October, both biomass and species diversity were reduced; prey consisted mainly of ants and afew beetle species. From November to March, biomass availability was intermediate, with the dietconsisting mostly of Tipulidae larvae, plants and dung beetles. Chough juvenile monthly survival was low inAugust, November and December. Annual variation in fledging success was correlated with prey biomassavailability in May.Conclusion - Seasonal variation in the availabilityof prey species and their biomass influences Choughdemography.

Evolution by natural selection has resulted in a remarkable diversity of organism morphologies that has long fascinated scientists and served to establish the first relations among species. Despite the essential role of morphology as a phenotype of species, there is not yet a formal, mathematical scheme to quantify morphological phenotype and relate it to both the genotype and the underlying developmental genetics. Herein we demonstrate that the morphological diversity in the beaks of Darwin’s Finches is quantitatively accounted for by the mathematical group of affine transformations. Specifically, we show that all beak shapes of Ground Finches (genus Geospiza ) are related by scaling transformations (a subgroup of the affine group), and the same relationship holds true for all the beak shapes of Tree, Cocos, and Warbler Finches (three distinct genera). This analysis shows that the beak shapes within each of these groups differ only by their scales, such as length and depth, which are genetically controlled by Bmp4 and Calmodulin . By measuring Bmp4 expression in the beak primordia of the species in the genus Geospiza , we provide a quantitative map between beak morphology and the expression levels of Bmp4 . The complete morphological variation within the beaks of Darwin’s finches can be explained by extending the scaling transformations to the entire affine group, by including shear transformations. Altogether our results suggest that the mathematical theory of groups can help decode morphological variation, and points to a potentially hierarchical structure of morphological diversity and the underlying developmental processes.

The evolution of the precision grips, in which an object is held between the distal surfaces of thumb and fingers and the power grip, in which an object is grasped with the palm, is poorly understood in spite of hypothesis stipulating an evolution from power toward precision grips. In human, numerous studies have shown that the external factors such as the size or the form of an object influenced grasp patterns whereas in non-human primates, those parameters are poorly known. The objective of the present study was to investigate the variation in the use of different grips according to the volume of the object for six primate species representative of the phylogeny: human, chimpanzee, orangutan, macaque, baboon and capuchin. For those species, the grasping patterns were examined during grasping of spherical objects of two different volumes. Frame-by-frame analysis of digit contact strategies indicated: (1) an effect of the species on the category of grasping whatever the volume of the object, (2) a high degree of species variability and (3) no individual difference whatever the species. These results are discussed in relation to its potential contribution to understand the evolution of grasping.

International audience; BACKGROUND: Human cytomegalovirus (HCMV) is the most common opportunistic pathogen infecting immunocompromised patients after transplantation. Although its immunomodulatory capacities and genomic variability participate in immune system evasion, they are poorly studied in clinical strains without culture amplification. One of HCMV immunomodulatory genes, UL40, confers HCMV-infected cells' protection from natural killer-mediated lysis through its encoded nonapeptide presented in the context of human leukocyte antigen-E. METHODS: In three renal transplant recipients with different HCMV serostatus, we aimed to evidence the co-evolution of mixtures of HCMV variants over time with sequencing and cloning of HCMV UL40 gene. RESULTS: Six months after renal transplantation in patient 1Bx, D+/R+, UL40 phylogenetic and bootscan analysis suggested the emergence of a recombination between two previous viral strains. In patient 8Bx, initially D+/R-, distribution of variants in five samples over 43 months was notably stable, with no visible emerging variants despite two renal engraftments and extended episodes of active infection. In patient 9Bx, also D+/R-, phylogenetic tree of viral variants revealed in the first sample a minor clone, confirmed by a specific polymerase chain reaction, related to the three subsequent dominant clones. CONCLUSIONS: In three HCMV-infected renal transplant recipients, we have evidenced different viral evolutive polymorphisms including point mutations, recombination, and occasionally suggesting the intervention of several HCMV strains or a quasispecies-like distribution. This variability could contribute to viral adaptability in pathogenesis.

International audience; Bird conservation can be challenging in landscapes with high habitat turnover such as planted forests, especially for species that require large home ranges and juxtaposition of diVerent habitats to complete their life cycle. The eurasian hoopoe (Upupa epops) has declined severely in western Europe but is still abundant in south-western France. We studied habitat selection of hoopoes in pine plantation forests using a multi-scale survey, including point-counts at the landscape level and radio-tracking at the home-range scale. We quantiWed habitat use by systematically observing bird behaviour and characterized foraging sites according to micro-habitat variables and abundance of the main prey in the study area, the pine processionary moth (Thaumetopoea pityocampa). At the landscape scale, hoopoes selected habitat mosaics of high diversity, including deciduous woods and hedgerows as main nesting sites. At the home-range scale, hoopoes showed strong selection for short grassland vegetation along sand tracks as main foraging habitats. Vegetation was signiWcantly shorter and sparser at foraging sites than random, and foraging intensity appeared to be signiWcantly correlated with moth winter nest abundance. Hoopoe nesting success decreased during the three study years in line with processionary moth abundance. Thus, we suggest that hoopoes need complementation between foraging and breeding habitats to establish successfully in pine plantations. Hoopoe conservation requires the maintenance of adjacent breeding (deciduous woods) and foraging habitats (short swards adjacent to plantation edges), and consequently depends on the maintenance of habitat diversity at the landscape scale.

SUMMARYOnly a few studies on quadrupedal locomotion have investigated symmetrical and asymmetrical gaits in the same framework because the mechanisms underlying these two types of gait seem to be different and it took a long time to identify a common set of parameters for their simultaneous study. Moreover,despite the clear importance of the spatial dimension in animal locomotion,the relationship between temporal and spatial limb coordination has never been quantified before. We used anteroposterior sequence (APS) analysis to analyse 486 sequences from five malinois (Belgian shepherd) dogs moving at a large range of speeds (from 0.4 to 10.0 m s–1) to compare symmetrical and asymmetrical gaits through kinematic and limb coordination parameters. Considerable continuity was observed in cycle characteristics,from walk to rotary gallop, but at very high speeds an increase in swing duration reflected the use of sagittal flexibility of the vertebral axis to increase speed. This change occurred after the contribution of the increase in stride length had become the main element driving the increase in speed– i.e. when the dogs had adopted asymmetrical gaits. As the left and right limbs of a pair are linked to the same rigid structure, spatial coordination within pairs of limbs reflected the temporal coordination within pairs of limbs whatever the speed. By contrast, the relationship between the temporal and spatial coordination between pairs of limb was found to depend on speed and trunk length. For trot and rotary gallop, this relationship was thought also to depend on the additional action of trunk flexion and leg angle at footfall.

International audience; Citizen science, defined as participation of the general public in scientific research, could significantly help scientists to address biodiversity issues, through (i) monitoring the state of biodiversity, (ii) framing indicators which synthesise and communicate information on the state of biodiversity, (iii) building scenarios to evaluate the plausible consequences of different policies. A key asset of citizen science is that participating citizens disseminate the information they gain, thereby increasing the profile of issues being researched. We review further benefits associated with biodiversity monitoring, indicators and policy scenarios, envisioned as collaborative tools between scientists and citizens. Such collaboration promotes both the scientific adequacy and social legitimacy of these tools, so that they can meaningfully inform debates and decisions on public policy.

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International audience; Two models of intra-cortical bone remodeling are presented in this work by accounting for the different time scales. The first model involves change of bone relative density following bone stress modification during short time. The second bone model is based on a combination of Finite Element Analysis and Genetic Algorithms. This model allows to simulate the bone structure evolution through several thousands of generations and by the way shows that mechanical factors control at least in part the phylogenetic signals.; Nous présentons dans ce travail deux modèles de tissu osseux cortical en considérant différentes échelles de temps. La première partie de l'étude est consacrée au remaniement osseux à court terme sous contraintes mécaniques. Ce modèle permet de simuler l'évolution de le densité osseuse suite à des modifications de l'environnement mécanique du tissu cortical sur des rats. La seconde partie présente un modèle d'évolution de la structure anisotropique osseuse en supposant que des facteurs mécaniques contrôlent, du moins en partie, les signaux phylogénétiques. Le modèle biomécanique de cette seconde partie est basé sur l'algorithme génétique et la méthode des éléments finis. Il a été appliqué sur de l'os cortical d'oiseaux.

We analyzed 51 adult pelvis (25 women, 26 men) by the software DE-VISU conceived by one of us, J. Hecquet. It allows the description of the pelvis as the keystone of the articular system linking vertebral column, pelvis and lower limbs. The variations of the sagittal pelvic parameter, “angle of incidence” (mean 54°), are mainly responsible of individual variation in sagittal spine curves. The extreme values of incidence (32°-76°) correspond to pathological situations. This angle was discovered by radiological observations. We elucidated the morphological components of this angle : a high angle of incidence, associated with a strong lumbar curvature, is correlated to a strong sacral slope, a curved sacrum, a low position of the sacrum in relation to iliac crests. A low angle of incidence, associated with a weak lumbar curvature, is correlated to a weak sacral slope, a rectilinear sacrum, a high sacral position in relation to iliac crests. The performances of the software DE-VISU gave results far superior to those we obtained by geometric morphometry. It benefits from previous studies and publications of the authors on rachis, pelvis and lower limb. Ability to represent each pelvic joint, particularly the two coxo-femoral joints, was crucial. Calculation of centers, radii, directional axes and covering arches of the acetabula allowed to quantify the parameters of their three-dimensional orientation. We put in light for the fist time these parameters. The angles of acetabular anteversion, inclination and covering arch revealed their high variations. These parameters establish the relationship between pelvis and mechanical axes of lower limbs through the femoral angles : angle of anteversion of the femoral neck, cervico-diaphyseal angle and bicondylar angle. DE-VISU introduced for the first time a “systemic analysis” of the pelvis : it is no longer considered as an isolated object but as a piece of an integrated articular system.

More data are provided on the recently described temnospondyl Iberospondylus schultzei from the Upper Carboniferous (Stephanian C) of the Spanish Puertollano Basin. It represents the only known occurrence of a Paleozoic stegocephalian in a Spanish basin. This taxon appears to be more closely related to eryopoids and dissorophoids than to edopoids, as shown by four synapomorphies. However, decay index and bootstrap analyses show that the presented phylogeny, like other recently published phylogenies of temnospondyls, is not robust. Recently published phylogenetic data do not resolve the position of Dendrerpeton in temnospondyl phylogeny. Iberospondylus appears to have lived in the coastal marine environment in which it was preserved. The Spanish material supports the suggestion that the temnospondyls were sometimes coastal, near-marine animals. The widely held idea that many temnospondyls possessed a tympanum is poorly documented; the stapes of this group is always more massive than that of similarly-sized extant tetrapods that possess a tympanum. Other arguments presented to support the presence of a tympanum in temnospondyls appear to be invalid. Therefore, the widely held thesis that a tympanum was present in temnospondyls is questioned.

This study aims to explore a new method for the comparison of hind limb movements in two types of athletic specialities (sprint and middle-distance running). The Procrustes method, which combines quantitative, visual and statistical features, is applied to the shape of the ankle and knee cyclograms by considering as a fixed point the mobile hip landmark. Procrustes superimposition of twenty-five cyclograms (10 for sprinters and 15 for middle-distance runners) was supplemented by statistical procedures (principal component analysis, discriminant function) to seek the main invariants and variant key-events of the dynamics of the running cycle. Cyclogram patterns are more a response to the technical requirements of the athletic speciality than to constraints imposed by morphology (hind limb length) and the runner's speed. The results provided useful gait indicators which may be used by trainers and athletes for assessment and improvement of running style aiming at strategies optimally adapted to the discipline.

The walking parameters of the tinamous (Tinamus solitarius, Crypturellus obsoletus and Rhynchotus rusfescens) and cariamids (Cariama cristata and Chunga burmeisteri ) were studied with the aim of verifying whether the duration of the swing phase is a discriminant parameter for paleognathous and neognathous birds. Tinamous are paleognathous birds as are the ratites, whereas the cariamids are neognathous birds sharing a cursorial adaptation with the large ratites. Osteological measurements of the long bones of the hind limbs, and frame by frame analysis of high speed video records of the birds walking under usual conditions, allowed for comparing duration of the swing phase in two functional categories: birds with long stretched-hind limbs versus those with short flexed-limbs. In addition were compared birds of two distinct phylogenetic groups: Neognathae vs Palaeognathae. Results indicate that there is a correlation between the duration of the swing phase and two studied clades, the paleognathous birds having a longer swing phase duration than neognathous birds belonging to the same functional categories. However, this parameter alone does not allow for discriminating between groups. The functional categories are also correlated to the duration of the swing phase as flexed-limb birds have a shorter swing phase than the stretched-limb ones. These data are congruent with several recent phylogenetic analysis results, placing the Tinamidae as a sister group of ratites within the Palaeognathae taxon.

The aim of this study was to identify shape patterns of the shoulder girdle in relation to different functional and environmental behaviours in turtles. The Procrustes method was used to compare the shoulder girdles (scapula and coracoid) of 88 adult extant turtles. The results indicate that four shape patterns can be distinguished. The shoulder girdles of (1) terrestrial (Testudinidae), (2) highly aquatic freshwater (Trionychidae, Carettochelyidae) and (3) marine turtles (Cheloniidae, Dermochelyidae) correspond to three specialized morphological patterns, whereas the shoulder girdle of (4) semi-aquatic freshwater turtles (Bataguridae, Chelidae, Chelydridae, Emydidae, Kinosternidae, Pelomedusidae, Platysternidae, Podocnemididae) is more generalized. In terrestrial turtles, the long scapular prong and the short coracoid are associated with a domed shell and a mode of locomotion in which walking is predominant. By contrast, highly aquatic freshwater turtles share traits with marine turtles. In both, the short scapular prong and the long coracoid are associated with a flat shell, and swimming locomotion. The enlarged attachment sites of the biceps, coracobrachialis magnus, and supracoracoideus also give these strong swimmers a mechanical advantage during adduction and retraction of the arm. Increasing size leads to allometrical shape changes that emphasize mechanical efficiency both in terrestrial and in aquatic turtles.

Mabuya altamazonica sp.nov . is described from Peruvian Amazonia. This species is sympatric with M. nigropunctata. Despite their superficial similarity, those two Amazonian species could be differentiated both by cephalic scalation characters and molecular results (12S rRNA). Mabuya altamazonica sp. nov. differs from all Amazonian and Andean species of Mabuya by the combined presence of (1) paired prefrontals and frontoparietals, (2) a single pair of nuchals, (3) four supraoculars, (4) five subequal supraciliaries, (5) seven supralabials with the fifth being the largest and placed under the eye, (6) parietals in contact behind the interparietal and (7) dark palms and soles.

Mammals adopt a limited number of postures during their day-to-day activities. These stereotyped skeletal configurations are functionally adequate and limit the number of degrees of freedom to be controlled by the central nervous system. The temporal pattern of emergence of these configurations in altricial mammals is unknown. We therefore carried out an X-ray study in unrestrained rats from birth (P0) until postnatal day 23 (P23). The X-rays showed that many of the skeletal configurations described in adult rodents were already present at birth. By contrast, limb placement changed abruptly at around P10. These skeletal configurations, observed in anesthetized pups, required the maintenance of precise motor control. On the other hand, motor control continued to mature, as shown by progressive changes in resting posture and head movements from P0 to P23. We suggest that a few innate skeletal configurations provide the necessary frames of reference for the gradual construction of an adult motor repertoire in altricial mammals, such as the rat. The apparent absence of a requirement for external sensorial cues in the maturation of this repertoire may account for the maturation of postural and motor control in utero in precocial mammals (Muir et al., 2000 for a review on the locomotor behavior of altricial and precocial animals).

More data are provided on the recently described temnopondyl Iberospondylus schultzei from the Upper Carboniferous (Stephanian C) of the Spanish PuertollanoBasin. It represents the only know occurence of a Paleozoic stegocephalian in a Spanish basin. This taxon appears to be more closely related to eryopoids and dissorophoids than to edopoids, as shown by four synapomorphies. However, decay index bootstrap analyses show that the presented phylogeny, lile other recently published phylogenies of temnospondyls, is not robust. Recently published phylogenetic data do not resolve the position of Dendrepeton in temnospondyl phylogeny. Iberospondylus appears to have lived in the coastal marine

We compare Laetoli footprints (G1/35-36-37, G3/26) with modern humans (62 footprints), and a chimpanzee walking bipedally (five footprints). Video cameras allow us to capture walking parameters on a wet clay walkway, and the Procrustes method is used to analyze the footprint shape (outlines and centres of presure). Like humans, Laetoli hominids walked with small feet gap and probably low velocity (they used heels as brakes). They preserved certain ape-like traits (foot proportions, roll-off).They also possessed more marked human-like traits (small vault, metatarsal pressure, similar toe-off). Like humans walking on a soft ground, they flexed toes at ground contact, and then propelled themselves by pushing on the ball of the foot and on digits (hallux and lateral toes acting together) . The hypothesis of permanently flexed, or curled-underneath, digits was not retained by comparison with th chimpanzee.

SUMMARYMammalian locomotion is characterized by the use of asymmetrical gaits associated with extensive flexions and extensions of the body axis. Although the impact of sagittal spine movements on locomotion is well known, little information is available on the kinematics of spinal motion. Intervertebral joint movements were studied in two metatherian and three eutherian species during the gallop and halfbound using high-speed cineradiography. Fast-Fourier transformation was used to filter out high frequency digitizing errors and keep the lower frequency sinusoid oscillations that characterize the intervertebral angular movements. Independent of their regional classification as thoracic or lumbar vertebrae, 7±1 presacral intervertebral joints were involved in sagittal bending movements. In only one species, no more than five intervertebral joints contributed to the resulting `pelvic movement'. In general, the trunk region involved in sagittal bending during locomotion did not correspond to the traditional subdivisions of the vertebral column (e.g. as thoracic and lumbar or pre- and postdiaphragmatic region). Therefore, these classifications do not predict the regions involved in spinal oscillations during locomotion. Independent of the gait, maximum flexion of the spine was observed in the interval between the last third of the swing phase and touch-down. This results in a retraction of the pelvis and hindlimbs before touch-down and, we hypothesize, enhances the stability of the system. Maximum extension occurred during the first third of the swing phase (i.e. after lift-off) in all species. In general, the observed timing of dorsoventral oscillations of the spine are in accordance with that observed in other mammals and with activity data of respiratory and epaxial back muscles. Although no strict craniocaudal pattern was observable, the more cranial intervertebral joints tend to flex and extend earlier than the more caudal ones. This is in accordance with the organization and the activation of the paravertebral musculature in mammals. The amplitude of intervertebral joint movements increased caudally, reaching its highest values in the presacral joint. The more intense sagittal bending movements in the caudal intervertebral joints are reflected by the muscle fiber type composition of the back muscles involved. Despite the highly similar amplitude of `pelvic motion', touch-down and lift-off positions of the pelvis were clearly different between the species with a long, external tail and those with no external tail.

International audience; Evolutionary algorithms (EAs) use Darwinian principles—selection among random variation and heredity—to find solutions to complex problems. Mostly used in engineering, EAs gain growing interest in ecology and genetics. Here, we assess their usefulness in functional morphology, introducing finite element modelling (FEM) as a simulated mechanical environment for evaluating the ‘fitness' of randomly varying structures. We used this method to identify biomechanical adaptations in bone tissue, a long-lasting problem in skeletal morphology. The algorithm started with a bone tissue model containing randomly distributed vascular spaces. The EA randomly mutated the distribution of vascular spaces, and selected the new structure if its mechanical resistance was increased. After some thousands of generations, organized phenotypes emerged, containing vascular canals and sinuses, mimicking real bone tissue organizations. This supported the hypothesis that natural bone microstructures can result from biomechanical adaptation. Despite its limited faithfulness to reality, we discuss the ability of the EA+FEM method to assess adaptation in a dynamic evolutionary framework, which is not possible in the real world because of the generation times of macro-organisms. We also point out the interesting potential of EAs to simulate not only adaptation, but also concurrent evolutionary phenomenons such as historical contingency.

International audience; As changes in land uses have been mentioned as the main factor to explain decline of chough population across western Europe, a study was carried out in Ouessant (western France) in order to link territory quality with reproductive success. As such an approach could be hindered by the fact that reproductive performance of birds could be influenced by their breeding experience, we analysed both inter-and intra-nest site variation in fledging success. Territory quality was quantified combining habitat selection, territory size, amount of feeding area and distance between nest and feeding area. Feeding habitats positively selected by chough were characterized by a mean sward height lower that 5cm. Foraging area was on average of 21,557 m². Feeding areas (ie. feeding habitat within foraging area) close to the nest were preferentially used. Fledging success appeared not to be influenced by the total area of feeding areas in chough territory, nor by the mean feeding flight distance. But fledging success adjusted to nest site and year appeard to be influenced by feeding area close to the nest : one additional fledging was expected for each additional 10,000 m² of feeding habitat within 300m of the nest. These first results bring elements which allowed us to consider recommend landscape management measures to ensure a favourable conservation status of local chough populations

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Resume Je presente ici une courte synthese d'etudes personnelles recentes de la structure microscopique des os des oiseaux actuels. Par une approche comparative et statistique, il est montre que certains types de tissus osseux observes resultent vraisemblablement d'une optimisation de la resistance du squelette a des contraintes mecaniques, comme la torsion apparaissant au cours du vol. Ces relations adaptatives inedites entre la microstructure osseuse et la fonction biomecanique du squelette ouvrent des perspectives paleobiologiques nouvelles pour l'analyse du vol et de ses origines chez les vertebres, a partir des microstructures conservees dans les fossiles. Pour citer cet article : E. de Margerie, C. R. Palevol 5 (2006) .

During hominin evolution, an increase in the femoral bicondylar angle was the initial change that led to selection for protuberance of the lateral trochlear lip and the elliptical profile of the lateral condyle. No correlation is found during ontogeny between the degree of femoral obliquity and of the prominence of the lateral trochlear lip. Might there be a relationship with the elliptical profile of the lateral condyle? On intact femoral diaphyses of juvenile humans and great apes, we compared the anteroposterior length of the lateral and medial sides of the distal metaphysis. The two diaphyseal pillars remain equal during postnatal growth in great apes, while the growth of the lateral pillar far exceeds that of the medial pillar in humans. Increase in bicondylar angle is correlated with disproportionate anteroposterior lengthening of the lateral pillar. The increased anteroposterior length of the lateral side of the metaphysis would contribute to increasing the radius of the curvature of the lateral condyle, but not to the projection of the lateral trochlear lip. The similar neonatal and adult femoro-patellar joint shape in humans prompted an assessment of the similarity during growth of the entire neonatal and adult epiphyses. We showed that the entire epiphysis undergoes drastic changes in proportions during postnatal growth. Finally, we emphasize the need to distinguish the cartilaginous phenotype and the ossified phenotype of the distal femoral epiphysis (and of any epiphysis) during postnatal growth. This crucial distinction applies to most postcranial bones, for they almost all develop following the process of endochondral ossification.

Resume L'etude comparee de la longueur, de la largeur et de la hauteur des vertebres successives qui constituent l'axe vertebral chez l'anguille (Anguilla anguilla), la truite arc-en-ciel (Oncorhynchus mykiss), le chinchard (Trachurus trachurus) et la bonite (Sarda orientalis) permet de confirmer que la colonne vertebrale presente une regionalisation morpho-anatomique plus complexe que la simple division en deux regions troncale et caudale classiquement admise. Avec les donnees morphologiques obtenues, il est possible de dresser quatre profils vertebraux differents et caracteristiques des quatre modes de nage de type axial ainsi representes : mode anguilliforme (anguille), mode pseudo-carangiforme (truite), mode carangiforme (chinchard) et mode thunniforme (bonite). Le positionnement relatif des maxima de longueur, hauteur et largeur vertebrales par rapport a la longueur des animaux est caracteristique du mode de nage axial ; tres proche de la tete dans le mode anguilliforme, il se situe pratiquement au milieu de la colonne vertebrale dans le mode subcarangiforme, alors qu'il est tres posterieur dans les modes thunniforme et carangiforme, qui apparaissent finalement relativement proches. Pour citer cet article : F.-J. Meunier, M.-Y. Ramzu, C. R. Palevol 5 (2006).

Resume Le but de l'etude est l'analyse quantitative des changements de conformation des cyclogrammes de la cheville en fonction de la specialisation des sprinters (courtes ou longues distances). Le protocole experimental consiste a realiser quatre sequences de course de 80 m a vitesse maximale. La superposition Procuste de 40 cyclogrammes (quatre par individu) a ete completee par des procedures statistiques (analyse en composantes principales, regression lineaire multivariee), afin de rechercher les variables cinematiques susceptibles d'exprimer l'effet de la specialisation. Les resultats revelent un changement de conformation du cyclogramme selon un continuum, allant des sprinters de 60 m aux sprinters de 100 m, 200 m, et 400 m. Plus les sprinters sont specialises sur de courtes distances, plus leurs cyclogrammes presentent une conformation fusiforme, et ceci independamment de leur vitesse durant l'experimentation. Les resultats suggerent que l'entrainement (visant a l'efficacite de la foulee) joue un role essentiel dans l'acquisition d'une coordination specifique en reponse aux exigences de chaque specialite de sprint. Pour citer cet article: L. Decker et al., C. R. Palevol 5 (2006) .

The compactness profile of femoral cross-sections and body size of 46 species of lissamphibians was studied to assess the relationship between lifestyle (aquatic, amphibious or terrestrial) and bone compactness. Two tests that incorporate phylogenetic information (permutational multiple linear regression incorporating phylogenetic distances and concentrated changes tests) show that the return to an aquatic lifestyle is associated with an increase in the compactness of the femur and an increase in body size. However, amphibious taxa cannot be distinguished from terrestrial ones on the only basis of size or compactness. Mathematical equations obtained from our data using logistic regression with phylogenetic weighting are used to infer the lifestyle of four early stegocephalians from the Permian and the Triassic. The results are generally congruent with prevailing palaeontological interpretations, which suggests that this method could be applied to infer the lifestyle of early taxa whose lifestyle is poorly understood.; Des sections transversales du fémur de 46 espèces de lissamphibiens ont été étudiées pour déterminer la relation entre mode de vie (aquatique, amphibie ou terrestre) et profil de compacité osseuse. Deux tests statistiques, qui incorporent la phylogénie, démontrent que le retour à un mode de vie aquatique chez les lissamphibiens s'accompagne d'une augmentation de la compacité fémorale et d'une augmentation de la taille corporelle. Cependant, les espèces d'amphibiens amphibies ne peuvent être distinguées de leurs proches parents terrestres uniquement sur la base de leur compacité fémorale ou de leur taille corporelle. Un modèle mathématique obtenu en utilisant des régressions logistiques qui incorporent une pondération phylogénétique nous a permis d'inférer le mode de vie de quatre stégocéphales du Permien et du Trias. Les résultats sont cohérents avec les interprétations précédentes. De plus, ils suggèrent que cette méthode pourrait fournir de précieuses données sur le mode de vie des premiers stégocéphales.

New material from a small, presumably adult enantiornithine bird (Saurischia: Aves) from the Lower Cretaceous of Las Hoyas (Spain) provides new data on the bone histology of those Mesozoic birds, which became extinct at the Cretaceous–Tertiary boundary. The material is referred to cf. Concornis lacustris. The outer cortex of the studied long bones is formed of a rather typical parallel-fibered bone tissue, with sparse flattened osteocyte lacunae, evidence of lines of arrested growth (LAGs) and no vascularization. This structure matches the outer circumferential layer (OCL) of many extant mature, small to tiny birds and also agrees with earlier descriptions of enantiornithine cortical bone. The deeper cortex progressively contains a much more plentiful component of osteocyte lacunae, which are more plump than flat. This region is also permeated by a few vascular canals surrounded by bone lamellae that form osteonal structures. The relationship of the osteonal material to the neighbouring primary tissue strongly suggests that the osteons are secondary. In some sections, it is possible to follow those osteons as formed by outward extensions from the endosteal bone tissue into the deep primary cortex. This specimen shows more histodiversity than the few enantiornithine samples previously reported. This further suggests that although growth may have been slow when the adult size was approached, it was more rapid at earlier stages. Even if as yet not enough is known of those early stages to document just how rapid early growth may have been, and whether enantiornithines grew differently from the basal avian models known from other early birds, the new data do not necessarily suggest that they had growth regimes quite distinct from extant birds of similar body sizes nor, by implication, completely different metabolic patterns or regimes. To cite this article: O. Cambra-Moo et al., C. R. Palevol 5 (2006).

Feeding in domestic vertebrates :from structure to behaviour , Feeding in domestic vertebrates :from structure to behaviour , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

SUMMARYWe investigated the effects of several behavioural conditions on the properties of the horizontal optocollic reflex (OCR) in pigeons. The head reflex was triggered by rotating the visual surroundings at different velocities (stimuli steps of 30-300 deg. s-1) and the characteristics of the slow and fast phases of the OCR were analysed during,(i) the `resting condition', in which animals were hung in a harness, (ii) the`standing condition', in which animals were freely standing, (iii) the`walking condition', in which animals were walking on a treadmill at different velocities, and (iv) the `flying condition', in which animals were hung in a harness and subjected to a frontal air-stream, provoking a flying posture.In the `resting' condition, irregularities were observed in the amplitude of nystagmic beats, in the beating field and in the slow phase velocity (SPV)of the OCR. These irregularities diminished progressively when the behavioural condition changed from `standing' to `walking', and disappeared in the`flying' condition. Correlatively, the working range of the OCR (evaluated by its gain at the plateau of SPV) was progressively extended toward higher stimulation velocities.The velocity of the fast phases of the OCR (measured for all the conditions except the `walking condition') also increased in correlation with the SPV. The walking speed did not influence the OCR in the treadmill velocity range of 0.20-0.40 m s-1. The presence of a frontal airstream in the`standing condition' did not change the OCR properties. This fact (and other observations discussed in the paper) suggests that the adaptation of the OCR to the behavioural context is mediated by internal signals generated by each behavioural condition.

The aim of this study was to assess pelvic asymmetry (i.e. to determine whether the right iliac bone and the right part of the sacrum are mirror images of the left), both quantitatively and qualitatively, using three-dimensional measurements. Pelvic symmetry was described osteologically using a common reference coordinate system for a large sample of pelvises. Landmarks were established on 12 anatomical specimens with an electromagnetic Fastrak system. Seventy-one paired variables were tested with a paired t-test and a non-parametric test (Wilcoxon). A Pearson correlation matrix between the right and left values of the same variable was applied exclusively to values that were significantly asymmetric in order to calculate a dimensionless asymmetry index, ABGi, for each variable. Fifteen variables were significantly asymmetric and correlated with the right vs. left sides for the following anatomical regions: sacrum, iliac blades, iliac width, acetabulum and the superior lunate surface of the acetabulum. ABGi values above a threshold of +/- 4.8% were considered significantly asymmetric in seven variables of the pelvic area. Total asymmetry involving the right and the left pelvis seems to follow a spiral path in the pelvis; in the upper part, the iliac blades rotate clockwise, and in the lower part, the pubic symphysis rotates anticlockwise. Thus, pelvic asymmetry may be evaluated in clinical examinations by measuring iliac crest orientation.

International audience; It is known that birds move by hopping in arboreal environments, but little attention has been given to the kinematics of such means of displacement. We have registered the movement patterns of a small South American ramphastid bird, the Lettered Aracari (Pteroglossus inscriptus), in branches of two different diameters (small and large) by means of a high-speed video camera (250 or 500 images/s). The locomotion parameters were estimated from the analysis of individual images. The displacement of birds takes place through out-of-phase hopping at an average speed of 1.68 ms -1 with movement frequency of 3.9 Hz (SD = 0.48). The two feet do not move simultaneously, but always with a relative phase of 0.044 s (SD = 0.014) between them during the phase of foot support contact, which represents about 15% (SD = 6%) ofthe locomotion cycle. In addition, Lettered Aracaris regularly change the sequence of foot support contacts during displacement. The trailing foot that looses contact with the perch during the hop is the second to touchdown again; at the same time the tail position also changes, moving towards the same side as this foot on touching the branch. Such aspect had not been registered for other birds; the characteristics of locomotion parameters during the arbore al displacements of the Lettered Aracari also differ from those found for ground hoppers with equivalent speeds.; Comportamento locomotor do Araçari-letrado (Pteroglossus inscriptus) (Ramphastidae).-Embora seja de amplo conhecimento que as aves locomovem-se, preferencialmente, por saltos no ambi-ente arborícola, pouca atenção tem sido dada a tal comportamento locomotor e aos parâmetros cinemáti-cos relacionados ao seu deslocamento. Assim, o Araçari-letrado (Pteroglossus inscriptus), um dos menores ranfastídeos de distribuição sul-americana, teve seu deslocamento em poleiros, de dois diferentes diâme-tros (fino e grosso), registrado por meio de uma câmara de vídeo digital de alta velocidade (a 250 ou 500 imagens/s). Os vídeos foram analisados, imagem por imagem, e os parâmetros locomotores estimados. Observou-se que tal deslocamento, durante os experimentos, foi sempre efetuado por meio de saltos defa-sados, a uma velocidade média de 1,68 ms-1 (± 0,40 ms-1), cuja freqüência dos movimentos foi de 3,9 Hz (± 0,48); tais saltos não são executados com ambos os pés movimentando-se simultaneamente, ou seja, ocorre sempre uma fase relativa entre cada um deles de 0,044 s (± 0,014 s) durante a fase de apoio dos pés, representando cerca de 15% (± 6%) do ciclo locomotor. Além disso, o Araçari-letrado inverte regular-mente a seqüência de apoio dos pés durante seu deslocamento: o pé que primeiro perde o contacto com o poleiro, durante o salto, é o segundo a se apoiar novamente, ao mesmo tempo em que a posição da cauda também se alterna, posicionando-se do mesmo lado deste pé. Tal aspecto não fora registrado para outras aves, assim como as características dos parâmetros locomotores durante o deslocamento arborícola do Araçari-letrado diferem daquelas encontradas para saltadores terrícolas em velocidades equivalentes.