1. Sensory modalities that allow tadpoles to assess their environment, and subsequently mediate their development, are not well understood. 2. By putting clay model tadpoles into the tanks with live tadpoles we have enhanced tactile and visual stimuli for tadpoles of three species ( Rana sylvatica , Bufo americanus and Xenopus laevis ) in a controlled fashion. The goal was to determine whether ...

Past confusion about leopard frog (genus Rana) species composition in the Tri-State area of the US that includes New York (NY), New Jersey (NJ), and Connecticut (CT) has hindered conservation and management efforts, especially where populations are declining or imperiled. We use nuclear and mitochondrial genetic data to clarify the identification and distribution of leopard frog species in this...

European water frog hybrids Rana esculenta (Rana ridibunda x Rana lessonae) reproduce hemiclonally, transmitting only their ridibunda genome to gametes. We compared fitness-related larval life-history traits of natural R. esculenta from Poland with those of the two sympatric parental species and of newly generated F1 hybrids. Compared with either parental species, F1 hybrid offspring had higher...

The apparent association constants of two agents, amiloride and triamterene, that block the Na-selective channel of apical membrane of frog skin are shown to decrease as the Na concentration is increased in the apical bathing solution in isolated skin of the frog, Rana temporaria, Rana esculenta, and Rana pipiens. These results were obtained in "normally polarized" skins. These effects were ind...