Clams are a new mob very similar to Shulkers, with a few exceptions:
-They are found at the lowest part of the ocean or near Ocean Monuments.
-They don't attack, but have lots of health.
-They drop Clam Shells, which can be combined with chests in a Crafting table to create a Clam Box, virtually the same as a Shulker Box.
-This can only be used if placed in water.
-Can be dyed.
-They provide an alternative rather than having to go to End Cities, find, and fight Shulkers.