Mollusks

Mollusks are invertebrate animals and just like the annelids they can be found in radically different environments, from the deepest abyss up to terrestrial habitats. They are highly diverse, not just in size and in anatomy, but also in behaviour and intelligence. One can be as stupid as a sponge, and an other one as clever as a monkey.

Humans know only a little less than 90,000 of them. In fact, molluscs represent 23% of all the marine organisms named by the Humans.