Dermal Fungicide Exposure at Realistic Field Rates Induces Lethal and Sublethal Effects on Juvenile European Common Frogs ( Rana temporaria )

Do common frogs ( Rana temporaria ) follow Bergmann ' s rule ?

Questions: Does intraspecific extension of Bergmann s rule – larger size within a species in cooler areas – hold true for ectotherms in general, and for the common frog (Rana temporaria) in particular? What is the relative importance of genetic and environmental factors (i.e. direct environmental induction) in determining latitudinal patterns of body size variation in common frogs? Methods: We ...

An unforeseen chain of events: lethal effects of pesticides on frogs at sublethal concentrations.

The field of toxicology has traditionally assessed the risk of contaminants by using laboratory experiments and a range of pesticide concentrations that are held constant for short periods of time (1-4 days). From these experiments, one can estimate the concentration that causes no effect on survival. However, organisms in nature frequently experience multiple, applications of pesticides over t...

Effects of Ethinylestradiol and the Fungicide Prochloraz on Metamor- phosis and Thyroid Gland Morphology in Rana temporaria

Several environmental xenobiotics have been found to affect the metamorphosis of amphibians. In this study we exposed tadpoles of the Common frog Rana temporaria from hatching to metamorphosis to two known endocrine disruptors, the estrogenic pharmaceutical 17 -ethinylestradiol and the antiandrogenic/antiestrogenic fungicide prochloraz to determine their effect on 1) days to metamorphosis and s...

Effects of Agriculture on Abundance, Genetic Diversity and Fitness in the Common Frog, Rana temporaria

Characterization of pancreatic endocrine cells of the European common frog Rana temporaria.

To characterize the endocrine cell types of the pancreas of Rana temporaria, conventional staining, silver impregnation, and immunocytochemical methods for light and electron microscopy have been applied to paraffin, thin and semithin sections, many of them serial pairs. Quantitative data on the frequency and distribution (insular, extrainsular among the exocrine cells, or within the pancreatic...