What is Animal Cognition? Study of non-human animal behavior Especially complex behavior Perception – light (UV & IR, polarity), sound, magnetic, electrical Cause and effect learning Concept formation – Time, number, relational Reasoning – Spatial, inferential, insight, tool use Memory - STM, LTM, implicit, explicit, Theory of Mind Self-awareness Communication – natural and artificial
Theory of Evolution by Natural Selection More offspring are born than survive There is variation among offspring Some are selected & have offspring Some of the qualities that enable offspring to survive are heritable What makes this hard to accept? Time scale Don’t observe (large) animals changing Contradicts creation myths Charles Darwin (1809-1882)
What is the biological significance of behavior? Study relation of organism to environment Adaptation – adaptive significance Descent of Man and Selection in Regards to Sex, 1871 Expression of Emotions in Man and Animals, 1872 Charles Darwin
Darwin & the Tree of Life BD (Before Darwin) AD (After Darwin)
Darwin and Animal Cognition Let man visit Ourang-outang in domestication, hear expressive whine, see its intelligence when spoken [to]; as if it understood every word said – see its affection – to those it knew – see its passion and rage, sulkiness, and very actions of despair; and then let him dare to boast of his proud pre- eminence. (Darwin, 1842/1987).
Behaviorism John D. Watson 1913 “Behaviorist Manifesto.” Behaviorists emphasized Classical and associative conditioning (cause and effect relationships). Found surprising similarities between species including humans. Concentrated on a few convenient ‘model’ species Greatly refined laboratory technique for the study of animal behavior Discouraged study of complex behavior, wide range of species, and behavior in the natural habitat.
Ethology Zoological tradition of studying animals in their natural habitats. Especially strong in Germany, Austria and the Netherlands Formalized into a distinct field of science in the 1930s under the title Ethology by Konrad Lorenz, Niko Tinbergen. Shared Nobel prize for medicine with Karl von Frisch 1973. Early “Classical” ethology emphasized role of instinct and other behaviors characteristic of (and more-or- less unique to) distinct species. Emphasis on diversity of behavior across species
Cognitive Psychology In the 1960s, psychologists grew tired of the ‘strictures’ of behaviorism. Cognitive Psychology encourages study of wider range of behavioral phenomena. Still experimental science. Less concerned with parsimony in explanation Tends to view human cognition as unique – therefore little purpose studying animals.
Clever Hans Horse in possession of retired school teacher, Mr. Von Osten. Could answer complex questions by stomping foot correct number of times. Arithmetic, including fractions Also questions requiring word answers by reference to a letter chart. Germany, 1890s
Clever Hans Not a circus trick. Investigated by commission including university professor, director of Hanover Zoo, an African explorer and two experts from the Prussian cavalry. “We were careful to state in our report that the intentional use of the means of training, on the part of the horse’s teacher, is out of the question… nor are there involved any of the known kinds of unconscious, involuntary aids.” Frankfurter Zeitung 1904.
Clever Hans Student, Oskar Pfungst, investigated further. Horse could not answer correctly unless questioner knew answer. Could not answer if questioner in a tent Aha! It’s something visual. “As soon as the experimenter had given a problem to the horse, he involuntarily bent his head and trunk slightly forward and the horse would then put the right foot forward and begin to top, without, however, returning it each time to its original position. As soon as the desired number of taps was given, the questioner would make a slight upward jerk of the head. Thereupon the horse would immediately swing his foot in a wide circle, bringing it back to its original position.” Pfungst, 1911.
Clever Hans N.B. The trainer’s signals to the horse were involuntary and unconscious. IMPORTANT POINT: It is possible to cue an animal to the right answer in a test without intending to or realizing you’re doing it. E.g. by your eye movements We must always be open to the possibility that the animal is being cued by unintentional stimuli.
Anthropo – man morph - shape Anthropomorphism Tendency to see other species as being like us. Dr. Dolittle – children’s movies Anthropomorphism
Anthropo – man Centrism – in the center Anthropocentrism Tendency to see other species from a human perspective Anthropocentrism
How to compare species intelligence No animal is ‘more evolved’ than any other evolution has been going on the same length of time for all extant species Evolution does not have to lead to more complexity Simplicity can evolve too Since all animals have to adapt to the problems of their own niches, comparisons are unfair Nonetheless, people over the years have tried to find fair ways to compare intelligence and cognition
Brain size: relative Heavier animals have heavier brains more body to control Animals above line have more brain for their size than average animal Cephalization index K is brain size after taking account of body size
Brain size: relative Simple mammals K ~ 0.1 Other mammals K ~ 0.2 Primates/whales K ~ 0.3 Dolphins K ~ 0.64 Human K ~ 0.89
Brain size: relative What determines K? Birds fly – must keep weight down Dolphins live in water – weight unimportant Dolphin cortex only ¼ density nerve cells as land mammals Maybe should consider different parts of brain e.g. neocortex But birds don’t have cortex…
Learning set Performance on 2 nd trial seemed to correlate well with K index + + + + + Trial 1 + Trial 2 + Trial 3 +Trial 4
Cat Skunk Bluejay Dunnart Lemur Sq. Monkey Marmoset Rhesus Chimpanzee Mink Squirrel Rat Tree Shrew Ferret 40 60 80 100 Max Percent Correct, Trial 2 Learning Set: Comparisons Large – K - Small Performance on 2 nd trial seemed to correlate well with K index But birds & fat-tailed dunnart do better than they should
Comparisons are tricky Commonality vs. uniqueness As we survey Animal Cognition we shall see some processes that are highly conserved And others that appear to be unique