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Animal Sciences Commons

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Articles 1 - 5 of 5

Full-Text Articles in Animal Sciences

Microhabitat Use Affects Brain Size And Structure In Intertidal Gobies, Gemma E. White, Culum Brown May 2016

Microhabitat Use Affects Brain Size And Structure In Intertidal Gobies, Gemma E. White, Culum Brown

Culum Brown, PhD

The ecological cognition hypothesis poses that the brains and behaviours of individuals are largely shaped by the environments in which they live and the associated challenges they must overcome during their lives. Here we examine the effect of environmental complexity on relative brain size in 4 species of intertidal gobies from differing habitats. Two species were rock pool specialists that lived on spatially complex rocky shores, while the remainder lived on dynamic, but structurally simple, sandy shores. We found that rock pool-dwelling species had relatively larger brains and telencephalons in particular, while sand-dwelling species had a larger optic tectum and …


Cue Choice And Spatial Learning Ability Are Affected By Habitat Complexity In Intertidal Gobies, Gemma E. White, Culum Brown May 2016

Cue Choice And Spatial Learning Ability Are Affected By Habitat Complexity In Intertidal Gobies, Gemma E. White, Culum Brown

Culum Brown, PhD

Variation in the structural complexity of a habitat is known to have significant affects on the evolution of different populations and can shape behavior, morphology, and life-history traits. Here, we investigated whether habitat complexity influences a species’ capacity for spatial learning and cue choice by comparing the performance of 4 goby species from 2 contrasting habitats in a spatial task. Gobies were collected from dynamic, homogenous sandy shores and stable, spatially complex rock pool habitats. We trained fish to use a T-maze to find a hidden reward and asked whether they used local visual landmarks or body-centered methods for orientation …


Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne Feb 2015

Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne

Travis J. Ryan

Hydroperiod, the time a temporary pond holds water, is an important factor influencing recruitment in amphibian populations and structuring amphibian communities. We conducted an experiment to test the effect of hydroperiod on metamorphic traits of the southern leopard frog (Rana sphenocephala), a common amphibian in the southeastern United States. We reared larval R. sphenocephala in artificial ponds at a density of 32 larvae per tank (initial volume = approximately 650 liter). We dried the tanks according to natural patterns, using three different hydroperiods (60, 75 and 90 d). Experimental hydroperiods had a significant effect on the number of metamorphs and …


Larval Life History And Abundance Of A Rare Salamander, Eurycea Junaluska (Plethodontidae), Travis Ryan Feb 2015

Larval Life History And Abundance Of A Rare Salamander, Eurycea Junaluska (Plethodontidae), Travis Ryan

Travis J. Ryan

The larval life history of Eurycea junaluska was studied in three southwestern North Carolina populations. Populations were sampled quarterly over a 13 mo period and size-class analyses were used to evaluate the pattern of larval growth and metamorphosis. Young of the year appeared in the late spring and experienced rapid growth through the first summer. Growth slowed in the second year and metamorphosis usually occured in the summer at about 25.5 mo post-hatching, although some data suggest that either 1yr or 3yr larval periods may be possible. The overall larval growth rate of E. junaluska is estimated at 1.27 mm/mo, …


The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts Dec 2014

The Influence Of Topographic And Dynamic Cyclic Variables On The Distribution Of Small Cetaceans In A Shallow Coastal System, Marijke N. De Boer, Mark P. Simmonds, Peter J.H. Reijnders, Geert Aarts

Mark P. Simmonds, OBE

The influence of topographic and temporal variables on cetacean distribution at a fine-scale is still poorly understood. To study the spatial and temporal distribution of harbour porpoise Phocoena phocoena and the poorly known Risso’s dolphin Grampus griseus we carried out land-based observations from Bardsey Island (Wales, UK) in summer (2001–2007). Using Kernel analysis and Generalized Additive Models it was shown that porpoises and Risso’s appeared to be linked to topographic and dynamic cyclic variables with both species using different core areas (dolphins to the West and porpoises to the East off Bardsey). Depth, slope and aspect and a low variation …