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What is Animal Cognition?. Lecture 1. “ Housekeeping ”. Cognition, broadly defined, means the processing of information in order to make informed choices …. but when animals are concerned, the definition becomes muddied.
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What is Animal Cognition? Lecture 1
Cognition, broadly defined, means the processing of information in order to make informed choices… but when animals are concerned, the definition becomes muddied
Views of animal cognition seem to swing, pendulum-style, from one extreme view to another…. Furred or feathered human Mindless robot
Although we can could discuss humans’ views of animals in numerous civilizations throughout recorded history, we’ll concentrate on Western, fairly modern civilization, if only to keep this lecture to within a reasonable length
On the mindless robot side, we have proponents like Descartes and the mid-20th century behaviorists….. On the furred, feathered human side we have proponents like Romanes and Griffin.
I hope at the end of the class, you’ll come to believe that the answer lies somewhere in the middle…
In his Meditations in the 1600s, Rene Descartes argued that animals • are purely physical entities, • lack mental and spiritual substance, • can’t reason, think, feel pain or suffer, • are machines with no consciousness
He surmised that they might have some fleeting responses to stimuli, but argued that they definitely could not think because they • couldn’t use or didn’t have language • demonstrated behavior that was not all that adaptable • reacted mostly instinctually
Now, Descartes was not the only one to present this stance, but his writings were widely accepted and fit in with the general view of animals as creatures that existed only for the benefit of humans: as sources of food, beasts of burden
And it’s much more difficult to justify such a stance if one believes that animals are sentient beings, more similar to, than different from, humans
Although, as we will see, no animal exhibits behavior that is identical to that of humans so as to totally contradict Descartes, many animals exhibit behavior patterns with many elements that approach that of humans, suggesting a continuum
In the 1800s, Romanes, on the heels of the publications of Darwin, began to address the inconsistencies in Descartes’ position
In 1871, Darwin stated: “the difference in mind between man and the higher animals…is one of degree, not of kind” To some extent, Darwin, but mostly Romanes, went about collecting a huge number of anecdotes to support this idea
Romanes classified these anecdotes by phyla and species in order to establish a continuum from single-celled organisms to humans…. The idea was to find a precise phyletic point at which a particular “new” mental ability emerged
The upshot were great “chains of reason”, with humans at a pinnacle; the big problem was that Romanes’ material was simply anecdotal, depending on human recollections and lacking any level of control An example:
On ants: Another time I found a very few of them passing along at intervals. I confined one of these under a piece of clay at a little distance from the line, with his head projecting. Several ants passed it, but at least one discovered it and tried to pull it out, but could not. It immediately set off at a great rate, and I thought it had deserted its comrade, but it had only gone for assistance, for in a short time about a dozen ants come hurrying up, evidently fully informed of the circumstances of the case, for they made directly for their imprisoned comrade and soon set him free. I do not see how this action could be instinctive. It was sympathetic help, such as man only among the higher mammalia shows. The excitement and ardour with which they carried on their unflagging exertions for the rescue of their comrade could not have been greater if they had been human beings. This observation seems unequivocal as proving fellow- feeling and sympathy, so far as we can trace any analogy between the emotions of the higher animals and those of insects.
This material, as written, probably seems totally off-the-wall and unbelievable…. And it was just these kinds of reports that really acted to discredit Romanes—for decades— as a serious scientist Moreover, neurobiology seemed at first to be against Romanes
Researchers argued that certain brain areas— specifically those in what was called the cerebral cortex— were necessary for intelligent behavior And, creatures such as reptiles and birds lacked this brain area
Songbird Human
And even in other mammals, including our nearest relatives, the apes, the area was considerably smaller…. even if, as much later researchers argued, one took into account brain-body ratios
So it seemed as though the term “animal intelligence” or “animal cognition” was an oxymoron… But, before we go on…. Let me get jump ahead chronologically in terms of brain data …
First, papers that came out just about two years ago show that birds, at least, not only have bits of brain that are equivalent to human cerebral cortex, but that for some species, this area has about the same brain/body ratio as in primates
Fig. 10. Scatterplot using independent contrasts of primate and psittaciform data, of log-transformed telencephalic volumes (mm3) against log-transformed body mass (g) contrasts; Psittaciforms are indicated by the gray circles and the primates are indicated by the open circles.
And, as we will see later in the semester, those birds with such large areas (the crow and parrot family) perform at about the level of young humans
Second, an article in the January 12th, 2006 issue of the journal Nature reports evidence for teaching in ants: • They performed less efficiently than they would outside the “classroom” • Their pupils learned faster than they would have learned by themselves • Feedback existed between teacher and pupil
So, although Romanes likely over-interpreted what he did find, some grain of truth likely existed in his material But back at the turn of the last century, Romanes’ material was thought to be so outre that the pendulum swung wildly in the opposite direction….
Enter Morgan, who, in reaction to Romanes’“mentalistic” approach, formed his famous canon: In no case may we interpret an action as the outcome of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale (1894).
Or, in its revised version of 1903: In no case is an animal activity to be interpreted in terms of higher psychological processes, if it can be fairly interpreted in terms of processes which stand lower in the scale of psychological evolution and development.
Add the comments of Thorndike (1898): • “… anecdotes give really the abnormal or super-normal psychology of animals.” • Scientists “…have looked for the intelligent and unusual and neglected the stupid and normal.” • “Only a single case is studied, and so the results are not necessarily true of the type; the observation is not repeated, nor are the conditions perfectly regulated; the previous history of the animal in question is not known.”
And: • “Such observations may tell us, if the observer is perfectly reliable, that a certain thing takes place, but they cannot assure us that it will take place universally among the animals of that species, or universally with the same animal.” • “Nor can the influence of previous experience be estimated.”
Basically, the argument was that if a behavior could be interpreted as • a simple response to a given stimulus, • an instinctual reaction, • or anything that did not require any level of information processing, THAT was how it should be viewed.
Morgan’s canon led to a very different approach to animal studies…. The good part was that careful experimental design became an important criterion Again, from Thorndike: • “To remedy these defects experiment must be substituted for observation and the collection of anecdotes.”
Thorndike argued that: • “You can repeat the conditions at will, so as to see whether or not the animal's behavior is due to mere coincidence.” • “A number of animals can be subjected to the same test, so as to attain typical results.” • “The animal may be put in situations where its conduct is especially instructive.”
Whether the next part was good or bad depends on one’s point of view…
The idea that there was some kind of continuum of intelligence began to wane Instead, researchers became concerned with discovering general mechanisms and laws of learning that applied across all phyla
Although researchers expected to find quantitative differences in learning across species, they believed that the underlying principles would be the same. And, critically, all such experiments were to be carried out in a sterile lab, where all conditions could be controlled.
By isolating the animal, one would avoid all extraneous input and be able to determine what was left —the basic ability— with respect to intelligence
Of course, such a stance did not appreciate that the absence of social stimuli of the environment or of other individuals was in and of itself a specific—and unnatural—situation for most animals
Models of behavior were now to be based on associationist principles: Simple laws were formulated to explain how external sensory input caused observable behavior (i.e., standard “stimulus-response” interpretations) Laws were few and were universal
Thus there was no need to examine “cognitive” skills, which, in part, included learning, remembering, problem-solving, rule and concept formation, perception and recognition
And one didn’t need to study a variety of species, because none would respond any differently from that of a pigeon or a rat And only the receipt of reward or punishment controlled behavior
So, an animal would see an environmental stimulus, such as a green-lit button in one location, and at some point in its random behavior it would come across another green button; if it pressed the button it got some reward A weak association thus formed between “green” and reward; if the animal hit a nearby red button instead, nothing happened, or it got a shock…and this latter behavior would thereby be ‘extinguished’ The next time the rat saw the buttons, hitting green was more likely because of the reward
At issue was not a memory for reward: Although some researchers did argue for memory, most didn’t care how the rat chose to behave, but rather only the extent to which it DID behave.. And researchers argued that any complex behavior could be broken down into a series of such simple S/R laws
These researchers, known as behaviorists, did have some initial success. They could explain how animals learned via trial-and-error on a number of laboratory tasks (things like maze running or adapting when the experimenter reversed the correct and incorrect choices)
And they had some success on ‘learning sets’ (e.g., Harlow), in which animals learned one task on one set of exemplars (e.g., to choose the odd object among three) and then responded more quickly when given the same task with different exemplars.
