To adaptively express inducible defenses, prey must gauge risk based on indirect cues of predation. However, the information contained in indirect cues that enable prey to fine-tune their phenotypes to variation in risk is still unclear. In aquatic systems, research has focused on cue concentration as the key variable driving threat-sensitive responses to risk. However, while risk is measured a...

A comprehensive analysis of tadpole-improved SU(2) lattice gauge theory is made. Simulations are done on isotropic and anisotropic lattices, with and without improvement. Two tadpole renormalization schemes are employed, one using average plaquettes, the other using mean links in Landau gauge. Simulations are done with spatial lattice spacings as in the range of about 0.1– 0.4 fm. Results are p...

Kin discrimination in cannibalistic tadpoles of the Green Poison Frog, Dendrobates auratus (Anura, Dendrobatidae). Cannibalizing a related individual can reduce the inclusive fitness of the cannibal. Hence, mechanisms that allow a tadpole to recognize and modify its behavior toward kin may reduce the inclusive fitness costs of cannibalism. Alternatively, ecological factors may cause preferentia...

Central respiratory chemoreceptors measure pH in the brain stem and are an integral part of the neural circuitry that modulates respiratory rhythmogenesis, specifically in response to hypercapnic acidosis. Central respiratory chemoreceptor membrane potential and/or action potential firing rate are altered in response to changes in intracellular pH (pHi), which changes with the hydration of CO2 ...

Anurans (frogs and toads) are unique among land vertebrates in possessing a free-living larval stage that, parallel to adult frogs, diversified into an impressive range of ecomorphs. The tempo and mode at which tadpole morphology evolved through anuran history as well as its relationship to lineage diversification remain elusive. We used a molecular phylogenetic framework to examine patterns of...

Thyroid hormone (T(3)) influences cell proliferation, death and differentiation during development of the central nervous system (CNS). Hormone action is mediated by T(3) receptors (TR) of which there are two subtypes, TRalpha and TRbeta. Specific roles for TR subtypes in CNS development are poorly understood. We analyzed involvement of TRalpha and TRbeta in neural cell proliferation during met...

Decreased plant diversity is expected to reduce ecosystem function. Although many studies have examined eff ects of plant species on trophic interactions, information regarding eff ects of native or non-native plant diversity on performance of individuals of higher trophic levels is limited. We reared larval American toad Anaxyrus americanus tadpoles in outdoor mesocosms containing litter of 1,...

BACKGROUND Global warming has been frequently demonstrated to increase growth rate in larval amphibians that have considerable phenotypic plasticity; this may lead to an increase in larval survival because large larvae are less likely to be captured by gape-limited predators. This study is to test whether warming could improve tadpole growth and thereby enhance the tadpole survival in plateau f...

The haemoglobins of Xenopus laevis have been studied by carboxymethyl-cellulose column chromatography and by polyacrylamide gel disk electrophoresis. In Xenopus tadpoles, 2 haemoglobins are found (Xenopus-HbFx and Xenopus-HbF^). Both haemoglobins persist throughout tadpole life: Xenopus-HbF\ is the main tadpole haemoglobin; Xenopus-HbFt is present in rather smaller amounts. The proportion of Xe...

Organ regenerative ability depends on the animal species and the developmental stage. The molecular bases for variable organ regenerative ability, however, remain unknown. Previous studies have identified genes preferentially expressed in the blastema tissues in various animals, but transcriptome analysis of the isolated proliferating blastema cells has not yet been reported. In the present stu...