aid of electron microscopy that paddlefish have electroreceptors on their rostrum's ampulla (hair cells) which are similar in structure to other Lorenzini.  The electroreceptors can detect weak electrical fields which not only signal the presence of prey items in the water column, such as zooplankton which is the primary diet of the American paddlefish, but they can also detect the individual feeding and swimming movements of zooplankton's appendages.  Paddlefish have poorly developed eyes, and rely on their electroreceptors for foraging.  However, the rostrum is not the paddlefish's sole means of food detection.  Some reports incorrectly suggest that a damaged rostrum would render paddlefish less capable of foraging efficiently to maintain good health.  Laboratory experiments, and field research indicate otherwise.  In addition tonovo hearing on the question of disability.  Irrespective of the Secretary's most recent determination, there can be no doubt that Parente has long suffered from serious physical and emotional disorders.  In 1976 she applied for and was granted Social Security disability benefits due to "emotional and various physical problems."    Prior to 1976 appellant had been treated for an ovarian cyst.  At the time the cyst was removed, appellant also had a pancreatic tumor removed, and a hysterectomy was performed.  Appellant was, and continues to be, extremely obese;  she is 5 feet 3 inches tall and weighs over 300 pounds, at one time being up to 347.  She cannot lean over to pick up things.  She has trouble breathing.