Any ichthyologists reading this? There are deep sea fish which have
developed long feelers as an alternative to eyes. Presumably they have
had longer to adapt to their essentially lightless environment. Some
deep sea critters, as you know, are bioluminescent. Perhaps in time
some cave animals would develop this. Altho, they'd all be blind by
then...

For once google fails me, for I can find nothing but vague references
to deep sea fish with feelers and useless eyes.

Kermit