Showing papers in "Zoology in 2014"

TL;DR: This paper simulated a biologically motivated motion detection algorithm to analyse motion signals generated by different areas on a zebra's body during displacements of their retinal images and suggested that the observer's visual system is flooded with erroneous motion signals that correspond to two well-known visual illusions.

TL;DR: Toepad size and claw length and height are tightly correlated with each other and with perch height, suggesting that the adhesive toepad and gripping claw have co-evolved to accommodate different habitats.

TL;DR: Analysis of magnitude and frequency components of COM motion in three dimensions in three fish species swimming with four locomotor modes at three speeds using high-speed video and an image cross-correlation technique suggests that fish have relatively low COM oscillations for their body size.

TL;DR: This short perspective paper reviews the evidence in support of each scenario and shows that the relationship between the nervous system of ctenophores and other animals is an unsolved, yet tractable problem.

TL;DR: It is suggested that allometry during early ontogeny may have evolved because it provides a survival benefit for small turtles.

TL;DR: It is speculated that resonance may not be a critical effect for efficient swimming in elongate, anguilliform swimmers, though it may be more important for stiffer carangiform and thunniform fishes.

TL;DR: Serially homologous systems with high internal differentiation frequently exhibit meristic constraints, although the developmental basis for constraint is unknown, which are regarded here as the nonadaptive, secondary consequences of adaptive respiratory and locomotor traits.

TL;DR: Individual fin rays in the middle of the anal fin curved substantially along their length during swimming, and the magnitude of this curvature was nearly twice the previously measured maximum curvature for ray-finned fish fin rays during locomotion.

TL;DR: The present results suggest that bamboo sharks can learn visual discrimination tasks, succeed in a reversal task and probably retain (some) information about a previously learned task when progressing to a new one.

TL;DR: It is hypothesized that the mechanical properties of the axial skeleton play a critical role in producing effective overland movement, and that tail-flip jumping species demonstrate enhanced elastic energy storage through increased body flexural stiffness or increased body curvature, relative to non-jumping species.

TL;DR: Realistic shark models are used to examine how altering predatory behavior and morphology influences escape behavior and performance in Squalus acanthias, a shark that is preyed upon by apex marine predators.

TL;DR: The use of eye darkening (ED) to indicate non-social stress in the fish Nile tilapia Oreochromis niloticus is expanded and high- and low-ED occur spontaneously, indicating different fish reactions to adjustments to a novel environment.

TL;DR: An examination of vertebral numbers across the major vertebrate clades finds that actinopterygian and chondrichthyan fishes tend to increase vertebral number in the caudal region whereas Sarcopterygii increase the number of vertebrae in the precaudal region, although exceptions to each trend exist.

TL;DR: The analyses have revealed that in certain basal insects the syncytial phase of oogenesis has been eliminated during evolution, and show that in the early meiotic oocytes of Thermobia, during the so-called bouquet stage, prominent Balbiani bodies (Bbs) are formed.

TL;DR: Investigating how functionally distinctive differences in sensory morphology are correlated with feeding behavior in the laboratory and determining the role of sensory systems in feeding ecology will provide insights into how sensory capabilities may contribute to trophic niche segregation.

TL;DR: The data support the idea that a specific gradient in material properties may be due to a variation in epidermis architecture (thickness/ultrastructure) and this variation may be an optimization of material properties for specific ways of life.

TL;DR: It is reported here that cownose rays have a greater number of pores than the yellow stingray, most of which are concentrated on the anterior ventral surface for both species, however, yellow stingrays have a broader arrangement of pores on both their dorsal and ventral surfaces than the cownOSE rays.

TL;DR: The developmental, morphological, and functional derivation of the tail from the axial trunk has resulted in a diversity of form, the attributes of which may be of ecological and evolutionary significance.

TL;DR: It is hoped these future combined analyses will identify certain morphological, mechanical, or kinematic parameters that might be associated with certain vertebral column functional regimes with respect to body stiffness.

TL;DR: It is demonstrated that in fact the extracellular-signal regulated kinases (ERK) form a decreasing gradient from head to tail to direct the reorganization of planarian body regionality after amputation.

TL;DR: The data suggest that the entire vertebral column of sharks, both joints and centra, is mechanically engaged as a dynamic spring during locomotion, and support the hypothesis that vertebra column strain in lateral bending is not limited to the intervertebral joints.

TL;DR: The structure of the ovary and the ultrastructural characteristics of oogenesis are not only remarkably similar in both Cyzicus and Lynceus, but also share morphological similarities with Notostraca as well as the basal hexapods Campodeina and Collembola.

TL;DR: It is concluded that the swimming behavior of Artemia is quite complex and diverse, and develops during ontogeny.

TL;DR: The discrepancy between the scaling of cross-sectional areas versus movements suggests changes in the energy storage and release mechanisms implicated in tongue projection in the veiled chameleon, Chamaeleo calyptratus.

TL;DR: The present study shows for the first time the possibility that U. unicorninctus swims in order to reproduce at night and that this swimming behavior is closely linked to the stranding of U. unicinctus individuals.

TL;DR: It is suggested that the S-start tends to occur with moderate body elongation, complementing the C-start in animals with this body form, and may be common in larvae but may be lost with body shape change through development.

TL;DR: The results suggest that splitting of the N and C clusters occurred around 6000 to 8400 years ago, and suggests that the current pattern results from human-induced factors and/or from the aridification process that occurred during the Holocene period.

TL;DR: Despite differences in diet, habitat and body size, the suite of neurological specialisations in the Tachyglossidae has been remarkably constant: encephalisation, sensory anatomy and specialisation, hypoglossal nerve size and cortical topography have all been stable neurological features of the group for at least 300,000 years.

TL;DR: It is demonstrated that hagfish possesses sclerotome-derived cartilaginous vertebral elements at the ventral aspect of the notochord and that the underlying developmental mechanisms are likely to have been conserved among extinct jawless vertebrates and modern gnathostomes.

TL;DR: The considerable regeneration of venom occurring within the first 48 h, despite the reduced protein content, suggests that predatory and defensive capacities are minimally constrained by the timing of venom replacement.