what limits how large a marine animal can grow? What biologically prevents a kraken from existing?

Question

what limits how large a marine animal can grow? What biologically prevents a kraken from existing?

In: 2

Answer 1

Size is limited by food supply and the ability of the creature in question to be able to function.

Dinos grew so big because their food supply was huge and their growth was slow and steady over thousands of generations. Their bodies were able to adapt and grow stronger to be able to function at those large sizes.

Likewise, whales and elephants have slowly adapted to be larger and their bodies have adapted as well.

Sea animals, in particular, are limited by food supply mostly.

As to a giant squid/kraken, I’m sure there are giant versions out there, as the largest of whales have been noted to have massive scars from such creatures.