Platypus

The platypus looks like no other creature on Earth. Physically, it appears to be a hybrid blend of a bird, beaver, reptile, and otter, with additional characteristics not contained in any of these four. On cursory examination, the platypus has a bill that most [blank] that of a waterfowl, not the mouth of any known mammal. Yet it is not an ordinary bill. It is actually a well-designed sensory organ. Not a nose, but a highly sensitive electro-location sensor, detecting minuscule electrical impulses generated by its food source of small crustaceans and worms. No other mammal has a sensor so highly [blank] -- in fact; only one other mammal has this ability at all. Then [blank] are the webbed feet, similar to those found on otters. Unlike an otter, however, the webbing is far more pronounced on the front feet of the platypus, which it uses like paddles for swimming. [blank] in the water, the back feet are tucked into its body and hardly used at all.