Publications by authors named "Ben D Bell"

A major focus in zoology is to understand the phenotypic responses of animals to environmental variation. This is particularly important when dealing with ectotherms in a thermally heterogenous environment. We measured body temperatures of a free-ranging, medium sized temperate reptile, the tuatara, Sphenodon punctatus, to investigate its thermal opportunities and the degree to which the animal actively regulates its body temperature.

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Studies on interspecific interactions between vertebrates based on thermal benefits are poorly represented in the literature. Ecologists know little about a category of thermoregulation termed kleptothermy. We provide evidence that a close association between a medium-sized reptile (tuatara, Sphenodon punctatus) and a small seabird (fairy prion, Pachyptila turtur) enables the reptile to maintain higher-than-average body temperatures.

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Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these.

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By investigating the mechanisms that underlie the perception of environmental cues, we may begin to understand how the sensory system governs behavioral responses. This is the first empirical study to examine learning and visual sensitivity in a reptile species, the tuatara (Sphenodon punctatus). We established a non-intrusive psychophysical method by employing an instrumental paradigm in order to examine discrimination learning and the ability to distinguish different flicker frequencies in the tuatara.

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Translocations are widely used to reintroduce threatened species to areas where they have disappeared. A continuum multi-species model framework describing dispersal and settling of translocated animals is developed. A variety of different dispersal and settling mechanisms, which may depend on local population density and/or a pheromone produced by the population, are considered.

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A controversial issue in anuran systematics is the relationship of Leiopelma to other anurans because recent phylogenetic constructions imply different relationships among the basal frogs. Of particular evolutionary interest is whether early development of Leiopelma resembles an ancestral salamander-like larva, an anuran tadpole, or neither. In the 1950s, Neville G.

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