Sublethal effects of toxicants can upset normal behavioural responses to predators, leading to increased predation. For example, sensory capabilities can be impaired by toxicants, leading to difficulty in detecting predators or other threats. Alteration of locomotor abilities by pollutants can also explain the difficulty of tadpoles to escape from predators. Here we assess the effects of a nitr...

Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are among the many pharmaceuticals detected in aquatic ecosystems. Although the acute effects of SSRIs on select organisms have been reported, little is understood about the chronic effects of these drugs on amphibians, which are particularly sensitive to environmental pollutants. Serotonin plays important roles in many physio...

Differences in host behavior and resistance to disease can influence the outcome of host-pathogen interactions. We capitalized on the variation in aggregation behavior of Fowler's toads (Anaxyrus [ = Bufo] fowleri) and grey treefrogs (Hyla versicolor) tadpoles and tested for differences in transmission of Batrachochytrium dendrobatidis (Bd) and host-specific fitness consequences (i.e., life his...

Many organisms use chemical defenses to reduce predation risk. Aposematic dendrobatid frogs sequester alkaloid-based chemical defenses from a diet of arthropods, but research on these defenses has been limited to adults. Herein, we investigate chemical defense across development in a dendrobatid frog, Oophaga pumilio. This species displays complex parental care: at hatching, mothers transport t...

Through time, the activity patterns, morphology, and development of both predators and prey change, which in turn alter the relative vulnerability of prey to their coexisting predators. Recognizing these changes can thus allow prey to make optimal decisions by projecting risk trends into the future. We used tadpoles (Lithobates sylvaticus) to test the hypothesis that tadpoles can extrapolate in...

Ranaviruses have been associated with most of the reported larval anuran die-offs in the United States. It is hypothesized that anthropogenically induced stress may increase pathogen prevalence in amphibian populations by compromising immunity. Cattle use of wetlands may stress resident tadpole populations by reducing water quality. We isolated a Ranavirus from green frog Rana clamitans (n = 80...

We examined the respiratory behaviours and swimming kinematics of Xenopus laevis tadpoles hatched in microgravity (Space Shuttle), simulated microgravity (clinostat) and hypergravity (3 g centrifuge). All observations were made in the normal 1 g environment. Previous research has shown that X. laevis raised in microgravity exhibit abnormalities in their lungs and vestibular system upon return t...

If an organism's juvenile and adult life stages inhabit different environments, certain traits may need to be independently adapted to each environment. In many organisms, a move to a different environment during ontogeny is accompanied by metamorphosis. In such organisms phenotypic induction early in ontogeny can affect later phenotypes. In laboratory experiments we first investigated correlat...

The present paper describes a sequential study of the leukocyte profiles and the changes in morphometry and morphology of erythrocytes in the tadpoles of Polypedates teraiensis during their development and metamorphosis, that is, transfer from an aquatic mode to a terrestrial mode of life. Blood smears of 21 different stages (Gosner stage 26 to 46) of tadpoles were investigated. Population of e...