The star-nosed mole is a ferocious, deadly predator. With the 25,000 sensory organs on the 22 appendages of its nose, this mole can find any insect that has foolishly ventured into its underground dominion. The Smithsonian quotes biologist Kenneth C. Catania:
The star-nosed mole’s “nose” is not an olfactory organ, but a skin surface that mediates touch. Innervated by more than 100,000 sensory neurons, the star is probably the most sensitive and highly acute touch organ found on any mammal. Under a scanning electron microscope, the skin surface resolves into a cobbled landscape covered with tens of thousands of tiny epidermal domes. Each is about 60 µm in diameter, and each contains a circular disk in its center. Known as Eimer’s organs, these sensory protrusions cover the entire surface of the star’s 22 appendages. In total, a single star contains about 25,000 domed Eimer’s organs, each one served by four or so myelinated nerve fibers and probably about as many unmyelinated fibers. This adds up to many times more than the total number of touch fibers (17,000) found in the human hand—yet the entire star is smaller than a human fingertip.At the link, you can watch a video of this hunter at work.
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