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71.
MARCOS DARÍO ERCOLI FRANCISCO JUAN PREVOSTI ALICIA ÁLVAREZ 《Zoological Journal of the Linnean Society》2012,165(1):224-251
In this study, we analysed locomotory habits in extant predators and Sparassodonta species through geometric morphometric techniques and discriminant analyses of the distal humerus in anterior view, proximal ulna in lateral view, and tibia in proximal view. We included a wide sample of extant predators, and considered the phylogenetic and allometric structure in the data sets. We also included some Sparassodonta, a group of carnivorous metatherians that inhabited South America during the Cenozoic, and inferred their locomotory habits. Results suggest the presence of a close relationship between shape and locomotory habits, even after removing the shape component explained by phylogeny in the three postcranial elements. Terrestrial habits were inferred for Arctodictis sinclairi, Borhyaena tuberata, ‘Lycopsis’ longirostrus, and Thylacosmilus atrox. Some degree of cursoriality was highlighted in B. tuberata and T. atrox, and climbing abilities in ‘L.’ longirostrus, and to a lesser degree in B. tuberata. Scansorial habits were inferred for Cladosictis patagonica, Sipalocyon gracilis, Prothylacynus patagonicus, and Pseudonotictis pusillus, and in the case of C. patagonica, some digging ability was also tentatively inferred. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 224–251. 相似文献
72.
GUSTAVO A. LLORENTE MARTA VIDAL‐GARCÍA NÚRIA GARRIGA SALVADOR CARRANZA JUAN M. PLEGUEZUELOS XAVIER SANTOS 《Biological journal of the Linnean Society. Linnean Society of London》2012,106(1):210-223
Molecular evidence suggests that climatic fluctuations in the peninsulas of southern European during the Miocene and Pleistocene resulted in considerable genetic differentiation of organisms, probably following a ‘refugia within refugia’ model. We examined morphometric and meristic characters in museum specimens from the three Iberian clades of the smooth snake Coronella austriaca, previously described by molecular markers. We found sexual and interclade differences in scale counts and head shape. Sexes were dimorphic in the number of ventral and subcaudal scales, although sexual disparities in scale counts differed among clades. Moreover, discriminant and canonical analyses showed higher interclade differences in males than in females. The results obtained in the present study match those from molecular markers and confirm the population structure identified within Iberian C. austriaca. The observed sex discrepancy in this pattern suggests that males and females are subjected to different selective pressures along their Iberian distribution. In light of the above, C. austriaca may offer a useful model system in which to explore phylogeographical patterns in southern Europe, as well as the conflicts between processes driving morphological sexual divergence. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106 , 210–223. 相似文献
73.
VIOLETA MU
OZ‐FUENTES NICLAS GYLLENSTRAND JUAN J. NEGRO ANDY J. GREEN CARLES VIL 《Molecular ecology resources》2005,5(2):263-265
Hybridization with a close relative, the North American ruddy duck (Oxyura jamaicensis), is a major problem for the conservation of the endangered white‐headed duck (Oxyura leucocephala). We report the development of 11 microsatellite markers that can facilitate the identification of hybrids as well as the study of the population structure of both species across their distributions. These markers were tested in 63 white‐headed ducks and 50 ruddy ducks and show a larger diversity in the latter species. 相似文献
74.
R. JUAN J. PASTOR I. FERNANDEZ 《Botanical journal of the Linnean Society. Linnean Society of London》1994,115(2):133-143
Seeds of 12 species of Veronica from south-west Spain were examined with the scanning electron microscope and stereomicroscope. Based on seed shape, colour, cell shape and surface ornamentation, seven morphological types are recognized. Seeds of the different types are described, illustrated and compared. The distribution of seed types among taxa is given. A key to distinguish the different species or groups of species is provided. 相似文献
75.
Seeds of 24 taxa of Linaria from south-west Spain were examinedwith a scanning electron microscope and light microscope. Basedon seed features such as shape, surface ornamentation and cellshape, seven morphological types were recognized. Seeds of thedifferent types are described, illustrated and compared. A keyto distinguish the different species or groups of species isprovided. Copyright 1999 Annals of Botany Company Seed-coat, SEM, anatomy, Scrophulariaceae, Antirrhineae, Linaria . 相似文献
76.
At this time, it can be said that the available data obtainedfrom amphibians and reptiles as regards the endocrine pancreasis consistent with the much more extensive data known for themetabolic effects of insuilin and glucagon in mammals. Thereremain, however, many unexplored facets of the specific responsesof the pancreas and the target tissues in lower animals. 相似文献
77.
JUAN C. RUIZ‐GUAJARDO ADRIANA OTERO‐ARNAIZ TRAVIS TAYLOR GRAHAM STONE TRAVIS C. GLENN NANCY A. SCHABLE JOSEPH T. MILLER SONJA PREUSS ANDREW SCHNABEL 《Molecular ecology resources》2007,7(6):1138-1140
We isolated 11 polymorphic microsatellite markers from Acacia mellifera, a savannah woodland tree in sub‐Saharan Africa and southern Arabia. The loci were screened for polymorphism using 48 Kenyan individuals. Allelic diversity ranged from three to 19 per locus and the polymorphic information content varied from 0.287 to 0.893. These loci will be useful in studies of genetic structure, gene flow and breeding systems. 相似文献
78.
MIGUEL A. RENDÓN ARACELI GARRIDO JOSÉ C. GUERRERO MANUEL RENDÓN‐MARTOS JUAN A. AMAT 《Ibis》2012,154(2):379-388
After being fed by their parents, Greater Flamingo chicks store food in their crops, which protrude outwards. We allocated the crop profiles of chicks to four categories to assess the relationship between body mass and crop profile variation, and so determine whether crop size can be used as an accurate index of the amount of food ingested, and to determine the timing and frequency of provisioning. We registered changes in body mass and crop fullness in eight chicks captured with turgid crops and kept in captivity until constant mass was achieved. The meal mass ingested by the chicks during each parental feeding was around 18% of net chick mass and varied greatly with crop profile. Mean transition times between the four crop profile categories ranged from 6 to 14 h. Between 1998 and 2009, 34% of chicks caught for ringing in a breeding colony had empty crops. From crop profiles recorded during the handling of chicks, it was estimated that approximately one‐third of the chicks were fed in the evening and another third during the night. Our results have implications for the estimation of body condition indexes because body mass should be free of the influence of the mass of the food in the crop. 相似文献
79.
Yearling birds generally display duller colours than adults. This may be due to selection favouring birds with more intensely coloured plumage or to an increase in colour after the first complete moult. Most research to date on the topic has been carried out on species with structural plumage coloration or with carotenoid‐based coloration that is produced by the unmodified deposition of pigments. However, no study has been carried out on species whose carotenoids are metabolically modified before deposition. In this study, we assess age‐related changes in the carotenoid‐based coloration of European Serins, a species that metabolically processes carotenoids before they can be deposited into feathers. Birds were captured over consecutive years and we carried out both cross‐sectional and longitudinal analysis. Adults had significantly greater values of lightness and chroma than yearling birds. However, there were no changes in plumage colour when analysing the same individuals captured in subsequent seasons. Plumage lightness and chroma of adult males after moult were related to body mass, suggesting a role of body condition on plumage coloration. Our results suggest that changes in plumage coloration with age in European Serins are due to a selection process that favours more intensely coloured individuals. 相似文献
80.
A detailed knowledge of the habitat requirements of steppe birds living in farmland habitats is necessary to identify agricultural practices compatible with their conservation. The globally threatened Great Bustard Otis tarda is a partial migrant in central Iberia, but factors affecting its winter habitat use have not been identified. We assessed habitat differences between breeding and wintering areas and winter habitat selection of radiotagged migrant female Great Bustards in central Spain. Of 68 tagged females, 35% moved to wintering areas located 64.3 ± 24.0 km south of their breeding areas, and 80% wintered in a single area of c. 236 km2. A census of the population in this area identified it as one of the most important wintering areas of this species in the world, holding c. 1500 individuals. There were significant differences between breeding and wintering habitats of individually marked migrant females. Compared with breeding areas, wintering areas of migrant females were located further from roads and urban nuclei, had lower human population densities and area of urban developments, and a higher diversity of land‐use types, with less cover of cereals and more vineyards and olive groves. Within this area, radiotracked migrant females preferred sites with more vineyards and a lower land‐use diversity. Our results highlight the importance of traditional Mediterranean dry farmland mosaics, and suggest that different conservation strategies are needed for migrant and resident populations in winter to secure the conservation of suitable wintering habitat for Great Bustards in the Iberian Peninsula. 相似文献