The brainy cephalopods behaved about the same as lab rats under similar conditions, raising both neuroscience and ethical issues:
Highly intelligent invertebrates like these challenge our ideas of how life forms come to be intelligent. For one thing, unlike most intelligent life forms, octopuses are unsocial and short-lived. Some researchers think that octopuses were forced to become intelligent when, unlike their nautilus cousins, they lost their shells…
Well now, there’s an animal intelligence hypothesis we can test: Will we ever find a shelled creature that is as smart as the octopus?
Meanwhile, what to make of Ed Yong’s suggestion, “This gantlet of threats might have fueled the evolution” of octopus intelligence? Need alone does not by itself produce intelligence any more than fear of death by itself produces longer natural lifespans. A creature that needs intelligence but doesn’t have it might just as likely go extinct. There are some significant unknowns we need to fill in here.
News, “Octopuses get emotional about pain, research suggests” at Mind Matters News
Takehome: The smartest of invertebrates, the octopus, once again prompts us to rethink what we believe to be the origin of intelligence.
You may also wish to read:
Is the octopus a “second genesis” of intelligence? Can its strange powers provide insights for robotics or the human mind?
and
Scientists clash over why octopuses are smart New findings show, the brainy seafood breaks all the rules about why some life forms are smart.