Say what? Tadpoles hear through simple auditory system

Tadpoles can hear, except for a brief period during metamorphosis, when they go deaf while their auditory systems rewire for frog adulthood, say researchers who believe the work may provide a model for understanding how hearing develops in fetuses in the womb.

PROVIDENCE, R.I. -- Tadpoles can hear, except for a brief period during metamorphosis when they go deaf as their auditory systems rewire for adulthood.

Until the recent paper by Brown University researchers in the Proceedings of the National Academy of Sciences, scientists had assumed tadpoles were deaf, even though it's well known that adult frogs rely greatly on their sense of hearing to catch food, to find mates and to defend their territories.

For about 48 hours just before metamorphic climax, when front limbs and other adult features appear, tadpoles do not respond to sound through either their childhood underwater oval window "ears" or their maturing adult air-based auditory system. Tadpoles may be able to use their simple hearing to escape the indiscriminate appetites of hungry adult bullfrogs, speculate postdoctoral researcher Seth Boatright-Horowitz and Andrea Simmons, professor of psychology and neuroscience.

Beyond ecological adaptation, tadpole hearing may provide a model for understanding how hearing develops in fetuses in the womb.