Guest post from Stephen Zachary.
The past few weeks have seen a number of entertaining and interesting animal behavior articles published in academic journals. Entertaining because, well, who doesn’t get a kick out of the video above? Interesting because the findings prompt us to rethink, yet again, the nature of cognition.
In a letter published in Current Biology, cognitive scientist Mathias Osvath reports on a cunning chimp housed in a Swedish zoo. For over a decade, the chimp — who is ironically named Santino, Italian for “little saint” — has been hurling stones at visitors and tourists in aggressive displays of dominance. What’s noteworthy about Santino’s behavior is that he seemingly plans ahead for these outbursts by stockpiling his arsenal of stones in the early morning before any zoo patrons arrive. Santino also has a knack for identifying and chipping off weakened parts of his concrete enclosure in order to use those fragments in his attacks as well. Such forethought in non-human animals is rarely observed and suggests that this chimp can anticipate his future experiences of aggression. The ability to discriminate between memory and perceptual stimuli make Santino, in effect, a military genius of the chimpanzee world — perhaps they should rename him Sun Tzu or Patton.
Another paper, written by biologists at the University of Florida, describes the ability of city-dwelling mockingbirds to single out individual humans and distinguish threatening humans from mere passersby. The experiment called for the same researcher to boldly approach and threaten the mockingbirds’ nest on four successive days. Over the course of the four days, the mockingbirds were flushed from their nests at greater distances, issued a larger number of alarm calls, and increased their rate of attack against the intruder. On the fifth day, a different researcher approached and threatened the nest in the same manner, but the mockingbirds defensive behavior returned to the levels exhibited on the first day of the experiment, indicating that the birds were able to identify the repeating offender and tailor their responses based on their history with that individual.
Over a 23 day span, the authors found that the average mockingbird faces about 15,000 instances of humans venturing within five meters of their nest. By recognizing individuals and accurately assessing the danger they present, the mockingbirds are able to efficiently manage risk in the environment. The authors point out that this ability is likely an underlying factor in the mockingbirds’ ability to thrive in urban areas. Because the mockingbird is considered to be further from the top of the avian intelligence hierarchy than, say, parrots or corvids, the study is both novel and surprising.
Staying with the topic of bird brains, a separate study published recently showed that cockatoos have the ability to synchronize their movement to musical beats — a skill that has been widely considered distinctively human. In the video above, you’ll see the subject, Snowball, a twelve-year old cockatoo, head bobbing and leg lifting to the beat of his favorite song, “Everybody” by the Backstreet Boys. Despite his questionable taste in music, it’s clear that Snowball can cut a rug. In fact, he’s a better dancer than some of us. By slowing down and speeding up the tempo of the song, the researchers found that Snowball adjusted his head bobs to correspond with the rhythm; and, thus, the dancing observed was not simple mimicry of human movement he’s previously observed.
So why is Snowball the life of the party while our dogs and cats sit around like wet blankets? The hypothesis supported by the current study is that beat perception and synchronization rely on strong connections between the auditory and motor areas of the brain, which provide the neural wiring for vocal imitation shared by few species.
On the surface, animal studies inform us about the nature of other species, but they really prove invaluable when they are able help explain the evolutionary history of humans. The scientists writing about Santino and Snowball agree that these animals make excellent models for the study of planning and dance, and the results above allow us to design plenty of new experiments that might parcel out what is necessary and sufficient for some of our own mental phenomena.
But animal studies also force us to take a hard look at our notions of cognition, consciousness, and human uniqueness. Because these concepts have blurry meanings and are difficult to articulate, an old philosophy professor of mine simply referred to them as “the good stuff” — an umbrella phrase for all the properties that are important for personhood. And while we may not agree on what constitutes personhood, it appears that the world of “the good stuff” — to the extent that it is considered distinctively human — is shrinking. In other words, we learn of animal similarities to humans quicker than we evolve meaningful differences that separate us from the rest of the animal kingdom.
And whether we’re talking about a chimp that plans for the future or a dog that has a sense of fairness, what emerges is an idea of cognition that is not a go/no-go proposition. Instead, the evidence points to something along the lines of an continuum, with different species — and even individual humans — finding themselves at various points. When does an infant have a sense of psychological continuity that allows her to distinguish events in the past? When does she possess a theory of mind, with which she infers the mental states of others? If an animal exhibits some of the traits relevant to personhood, such as the ability to plan for the future, should we bestow greater ethical value on them? Spain seems to be going in that direction. Can science help us be more theoretically consistent about what aspects of life carry moral weight?
Now we’re venturing way too close to social issues, and the most prudent course of action is to take another look at Snowball cutting loose and have a chuckle.