Cetaceans like orcas cannot sleep too deeply or else they will drown. They sleep half their brain at a time. Newborn orcas and dolphins don’t sleep for the first month of their life.
I suspect that cetaceans have had to dramatically lower their learning rate in order to survive on limited sleep and as a result they have only mediocre intelligence despite their huge brains.
Cetaceans like orcas cannot sleep too deeply or else they will drown. They sleep half their brain at a time. Newborn orcas and dolphins don’t sleep for the first month of their life.
I suspect that cetaceans have had to dramatically lower their learning rate in order to survive on limited sleep and as a result they have only mediocre intelligence despite their huge brains.