For our experiments, we worked with

For our experiments, we worked with carbaryl (1-naphthyl N-methylcarbamate; commercial name, Sevin), one of the world’s most commonly used, broad-spectrum pesticides (an insecticide, acaricide, molluscicide, and ectoparasiticide). It acts by inhibiting acetylcholinesterase and has become popular throughout the world since 1959 because of its low toxicity to mammals and its relatively short lifetime in the environment. Whereas myriad tests of carbaryl toxicity have been conducted on birds, mammals, fish, and invertebrates, there are few pub- lished studies on amphibians. Past studies of amphibian re- sponses to carbaryl have found that carbaryl reduces tadpole activity and growth, and LC50 estimates vary between 2.5 and 20.6 mg