Agricultural pollutants may conspire with parasites to derail frog development in many regions of North America, according to a new study.
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Malformed frogs–with bent spines and extra or missing hind limbs–have been documented since the 1700s. However, since 1994, when Minnesota school children found deformities in many of the frogs they caught, unusually large numbers of malformed frogs have turned up from California to eastern Canada.