Comment by dan_mctree

Advanced intelligence may have evolve multiple times, but wouldn't the origins of simpler intelligence lie much deeper in the evolutionary tree? If Octopi use neurons too, it seems obvious to me that rudimentary intelligence must have originated in or before the common ancestor of vertebrates, octopi and squids: flatworms. Or going back even further, perhaps even all the way to single cellular life which often seems to be able to react in complex ways to stimuli. Even our brains seem to still make use of forms of processing within the cell, isn't there intelligence in those cells? Or do we have some agreed on definition of intelligence that excludes these simpler forms?