Cephalopod Cognition in an Evolutionary Context: Implications for Ethology
What is the distribution of cognitive ability within the animal kingdom? It would be egalitarian to assume that variation in intelligence is everywhere clinal, but examining trends among major phylogenetic groups, it becomes easy to distinguish high-performing generalists  whose behavior exhibits domain-flexibility  from specialists whose range of behavior is limited and ecologically specific. These generalists include mammals, birds, and, intriguingly, cephalopods. The apparent intelligence of coleoid cephalopods (squids, octopuses, and cuttlefish) is surprising  and philosophically relevant  because of our independent evolutionary lineages: the most recent common ancestor between vertebrates and cephalopods would have been a small wormlike organism, without any major organizational structure to its nervous system. By identifying the cognitive similarities between these organisms and vertebrates, we can begin to derive some general principles of intelligence as a biological phenomenon. Here, I discuss trends in cephalopod behavior and surrounding theory, and suggest their significance for our understanding of domain-general cognition and its evolution.
cephalopods ethology cognitive evolution comparative psychology