Showing papers in "Zoology in 2009"

TL;DR: The authors' analyses showed a strong phylogenetic component that obscured relationships between morphology and ecology and differences in claw morphology between species that appear to be related to microhabitat use (climbing versus terrestrial species), with the best ecological descriptors being claw length and height.

TL;DR: It is suggested that thermal biology in Phymaturus lizards may be evolutionarily or ecologically constrained and a significant association between climatic and thermal variables could be demonstrated for a set of syntopic Liolaemu lizards.

TL;DR: It is suggested that sexual dimorphism in bill size in Cory's shearwater is more likely driven by sexual selection related to antagonistic interactions than the foraging-niche divergence hypothesis.

TL;DR: Findings indicate that supercontraction can generate stress over a much broader range than previously reported, from 10 to 140 MPa, and suggests that spider silk achieves different molecular configurations depending upon the speed at whichsupercontraction occurs.

TL;DR: From measurements of ornamental and non-ornamental morphological characters and bite force in 105 chameleons, it is found that bite force is significantly related to head size and is best predicted by head width, a finding commensurate with the common framework for species radiations.

TL;DR: Positive allometry of biting performance appears to facilitate an earlier entry into the durophagous niche than would an isometric ontogenetic trajectory.

TL;DR: A review of the present SSD data for caecilians shows that many species are monomorphic for body size but show dimorphism in head size, while other species demonstrate female-biased SSD, and male- biased SSD has not been reported for caECilians.

TL;DR: Differences between climatic treatments were significant for body size but not for the wing-to-thorax ratio, suggesting that body size is more plastic than the ratio between different body components.

TL;DR: The photogenic pattern of the velvet belly lantern shark Etmopterus spinax was investigated over ontogeny to determine the scaling of the surface area and the photophore density of different luminous zones as well as the ecological consequences of ontogenetic variations in bioluminescence efficiency.

TL;DR: Gecko KA beta Ps show a central amino acid region of high homology and a beta-pleated conformation that is likely responsible for the polymerization of Ka beta Ps into long and resistant filaments.

TL;DR: Factors that constrain the stickiness of cribellar threads spun by members of the orb-weaving family Uloboridae in the Deinopoidea clade are examined and the material efficiency of these threads are compared with that of viscous capture threads produced byMembers of their sister clade, the Araneoidesa.

TL;DR: Investigation of the forestomach contents of free-ranging mouflon and roe deer shot during regular hunting procedures suggests that differences in forestomach physiology may occur across ruminant species.

TL;DR: This study examines the kinematics and morphology of the feeding apparatus of two geoemydid chelonians, the Malayan (Amboina) box turtle and the yellow-margined box turtle (Cuora flavomarginata), able to feed on land as well as in water.

TL;DR: The fiber type composition of these muscles in six small, extant therians similar in body shape to early mammals was investigated, suggesting that the described fiber type distribution is representative of the ancestral condition in mammals.

TL;DR: High-speed kinematics, whole-body lift measurements, and flow visualization suggest that, when swimming within 1cm of the bottom, poachers may use hydrodynamic ground effect to augment lift, thereby counteracting negative buoyancy.

TL;DR: A novel transgenic line which expresses enhanced green fluorescent protein (eGFP) specifically in the ectodermal epithelial cells is used to analyze the structure and shape of epithel cells as they are recruited into specific regions along the body column and respond to upstream signals such as components of the canonical Wnt signaling pathway.

TL;DR: In this article, the authors focus on variation of silk properties within different regions of cobwebs spun by the common house spider, Achaearanea tepidariorum, and suggest that spiders actively modify silk material properties during spinning in ways that enhance web function.

TL;DR: The central projections of the foreleg TO of the cave cricket are examined to conclude that T. neglectus interneurons are morphologically primitive with respect to those of hearing taxa, and significant changes in the dendritic structure/synaptic connectivity have taken place during the evolution of the most specialised first-order auditory interneuron of Ensifera.

TL;DR: The paired digits of artiodactyls are uneven in length, which suggests a different function during stance and weight bearing and it is conceivable that this asymmetry is the result of selection processes that favoured locomotion on soft ground.

TL;DR: Geometric morphometric methods can be an exceptionally useful tool for the study of differentiation of delphinid cetacean species and therefore provide some insights into their evolutionary history.

TL;DR: It is found that the timing of cartilage development varies between elements within a single species, as well as between species, and a tendency towards cartilage differentiation from uncondensed connective tissue in elements that form at the end of embryogenesis or after hatching is identified.

TL;DR: Results of this study are consistent with the hypothesis that glucocorticoids can have immunosuppressive effects and selective breeding for high locomotor activity may not have resulted in a generally compromised immune response.

TL;DR: This study measures the charge distribution around a dipole in seawater and confirms the close correspondence with the model and provides empirical evidence supporting a popular theoretical model and test predictions about how sharks will respond to a variety of different electric stimuli.

TL;DR: The quasi-normality of PaCO2 in large aquatic species breathing at rest, despite their exceptionally low f and normal metabolism, can be explained mainly by two factors, their large tidal volume/W, about three times the average terrestrial value, and their peculiar breathing pattern with sustained high lung volume during the expiratory pause.

TL;DR: It is found that oystercatchers from the study population had a Gompertz growth rate coefficient that was 2% less than predicted for body mass based on the equation for waders, and once a dominance relationship is established, the larger chick remains so during the pre-fledging period and this may improve their chances of survival.

TL;DR: The results confirm a strong relationship between CSD and the presence of CG, and the morphological and behavioural patterns associated with "CSD-CG" are opposed to the predictions postulated by the hypothesis of sexually antagonistic co-evolution.

TL;DR: Understanding patterns of growth in discrete elements of the Weberian apparatus allows us to hypothesize as to the specific developmental changes, likely constituting differences in gene expression in pathways involved in bone and cartilage differentiation, responsible for this morphological diversity.

TL;DR: It is concluded that normal somatic and gonadal growth of pre-puberal mice may be suppressed with an 8-hr phase relation of circadian serotonergic and dopaminergic oscillations, which accelerated the rate of gonadal maturation and led to more or less similar gonadal development as in the control mice.

TL;DR: The lesser electric ray, Narcine brasiliensis, is a small, demersal ray capable of generating electricity through its main and accessory electric organs, and it is hypothesized that the main electric organs are used for predator defense rather than feeding and that the accessoryElectric organs, specific to this species, are used in intraspecific communication.

TL;DR: The presence of a four-bar linkage that facilitates these kinematics by couplings between the pectoral girdle, urohyal, hyoid complex, and the neurocranium-suspensorium complex is confirmed.