My understanding is that mollusks generally can’t get very large because they have an open circulatory system. How is the giant squid so large if they are mollusks? When I try to look it up I don’t really get an answer. My question isn’t why gigantism is a good adaptive trait for them or what an open circulatory system, I just don’t understand how they get so huge when the rest of their phylum stays relatively small? Thanks