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Biomedical subjects

Andrew R Blaustein

Publications and source records attributed to Andrew R Blaustein.

3 recordsLinked to original sources

Effect of predator diet on life history shifts of red-legged frogs, Rana aurora.

Larval red-legged frogs (Rana aurora) are known to exhibit antipredator behavior in response to both chemical alarm cues released from injured conspecifics and chemical cues of predators. In some cases, the response to predators is dependent on the predator's diet. In this experiment, we tested whether long-term exposure to predator chemical cues and alarm cues resulted in alteration of life history characteristics of red-legged frogs. We raised groups of tadpoles in the presence of chemical cues of predators that were either fed conspecifics or heterospecific caddis-fly larvae, chemical cues of injured conspecifics, or a no-cue control. Tadpoles raised in the presence of either a predator fed conspecifics or cues of injured conspecifics metamorphosed earlier and at a smaller size than those exposed to predators fed heterospecifics or the no-cue control. The result suggests that red-legged frogs exhibit a life history shift in response to predatory cues and that this response is dependent on the diet of predators.

Animals↗

Amphibian defenses against ultraviolet-B radiation.

As part of an overall decline in biodiversity, amphibian populations throughout the world are disappearing. There are a number of potential causes for these declines, including those related to environmental changes such as increasing ultraviolet-B (UV-B) radiation due to stratospheric ozone depletion. UV-B radiation can kill amphibian embryos or can cause sublethal effects that can harm amphibians in later life stages. However, amphibians have defenses against UV-B damage that can limit damage or repair it after exposure to UV-B radiation. These include behavioral, physiological, and molecular defenses. These defenses differ interspecifically, with some species more able to cope with exposure to UV-B than others. Unfortunately, the defense mechanisms of many species may not be effective against increasing persistent levels of UV-B radiation that have only been present for the past several decades due to human-induced environmental damage. Moreover, we predict that persistent UV-B-induced mortality and sublethal damage in species without adequate defenses could lead to changes in community structure. In this article we review the effects of UV-B radiation on amphibians and the defenses they use to avoid solar radiation and make some predictions regarding community structure in light of interspecific differences in UV-B tolerance.

Amphibians↗