Primates are smart, even the “dumb” ones. When I say the “dumb” ones, I mean those that score lower on our measurements of intelligence and have smaller brains relative to body size than species that we usually consider very bright [e.g. capuchins, chimpanzees, bonobos, spider monkeys, etc…]. Despite being the “dumb” ones, these primates have bigger brains and score higher on measures of intelligence than most other mammals species. As an Order, Primates have big brains, live in complex social worlds, and eat food that is often widely dispersed and unpredictable [except for some folivores]. They rely heavily on learned behavior for everything from finding food to finding mates, devote a lot of energy to single, or a few offspring at a time, and they take a really long time to grow up. In fact, primates have the longest pre-reproductive life history stages of animal mammal, including elephants and whales. This trait is most exaggerated in our own species, in which most females do not begin reproducing before the age of sixteen, and most males do not take on the characteristics of an adult male until the age of twenty, or so. Among the non-human primates, we see a similar trend, though it is nowhere near as extreme as is the one observed in humans. Even so, all of these factors and traits combine in our biological Order to result in extremely long lived, slowly maturing organisms that spend a lot of energy trying to successfully raise one offspring at a time and have great big brains. The end result: Primates are smart, even the “dumb” ones.
Having said all of this, the question remains, how do we know primates are smart? To answer that question, we have to know just what “smart” is. In other words, we have to find a good measure of intelligence. Intelligence usually refers to the intellectual capacity of individual, which in many cases simply means their ability to reason, or comprehend a situation, to problem solve. The problem with this definition, and attempts to measure this kind of intelligence in non-human primates is that this is a very human definition of intelligence. Reasoning, comprehension and problem solving are all mental characteristics that are important to the survival and reproduction of humans. The end result is that intelligence is only measured in an anthropomorphic way. We have very few, if any purely objective measures of intelligence, which are not put in a human context. While these are, usually, useful for understanding how smart animals are relative to us, they may not tell us how smart they actually are. For example, an animal’s ability to solve a human constructed problem may have nothing to do with its ability to survive and find mates in its natural habitat. So, the questions should be posed: Does intelligence exist outside of the human construct? If it does, is it important to other animals, and how can we measure it objectively? While there has been a lot of work on this over the last few years, completely satisfying answers have not yet emerged. Instead of recapping them here, I would like to hear what you all have to say. What do you think intelligence is? How should it be defined and studied? Does it matter?