Intelligence for sentient beings has been defined as the ability to perceive or infer information, and to retain it as knowledge to be applied towards adaptive behaviors within an environment or context. For example, monkeys have learned how to use rocks to crack the shells of nuts to feed themselves. Corvids (including crows and ravens) have been seen to insert a straw to extract food from a test-tube. These adaptive behaviors are taken as signs of intelligence in the animal kingdom. However, there are no universal criteria for measuring animal intelligence. If someone asks, “Is the wolf smarter than the domestic dog?,” the simple answer is that wolves are smarter at what wolves do (e.g. hunt in packs) and dogs are smarter at what dogs do (ingratiate themselves to their masters to get food and shelter.) That is, intelligence is a measure of how well a species can gather information and apply it to solving problems in a changing environment.
Until recently, it was believed that humans were the only species with a capacity for abstract thought, but extensive observations of animals reveal that abstract problem solving and pattern recognition are not the sole preserve of humans. Animals show remarkable adaptive behaviors when their environment changes. Borrowing an expression from Charles Darwin, we would say that the difference in the intelligence of humans and the other animals is a difference in degree rather than in kind.
For over a century, researchers have attempted to define and measure human intelligence. Though a variety of definitions have appeared, psychologist Linda Gottfredson has achieved some consensus of this elusive human trait in her description:
Intelligence is a very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience. It is not merely book-learning, a narrow academic skill, or test-taking smarts. Rather, it reflects a broader and deeper capability for comprehending our surroundings, “catching on,” “making sense” of things, or “figuring out” what to do.
Since we can observe all the foregoing elements of human intelligence, albeit to a more limited degree, in animals it’s difficult to distinguish between human and animal intelligence, except to say that we have a greater capacity for abstract thought, pattern recognition, and abstract problem solving.
