Evidence for a relationship between geotaxis and seasonal movements in the toad Bufo americanus.

When activity data (i.e. crossings on a strip of fine sand) were compared with data acquired using an inclined plane, a relation of geotaxis to vertical movements was evident. We conclude that Bufo americanus has the ability to use geotaxis in its orientation in areas where topography is abrupt and breeding pools are in the bottom of valleys.