While many of us have eaten clams before, fewer of us see them interacting with their environment. Clams feed by siphoning water and filtering it for plankton, so it might surprise you to see a recent video that appears to depict a clam 'licking' salt from a table using its 'tongue.'
The 'tongue' is actually the clam's foot, which it uses to dig and anchor to its surroundings. So it's not actually eating anything at all.
"It's probably trying to find a place to dig. I doubt the salt has anything to do with it," said Scripps Institution of Oceanography biologist Miriam Goldstein to io9.
With that being said, Goldstein pointed to a number of explanations for its behaviour. "It is possible that the salt on the table is hurting the clam, which is why it withdraws its foot after touching it," the biologist told the Daily Mail. "[It is also] possible that the clam does not care about the salt at all."