Intelligence has been defined as the ability to achieve complex goals in complex environments. Some animals clearly are better than this at others. Humans are the smartest animals on the planet. Even some of the least intelligent humans can solve problems no animal could hope to.
Aside from humans, what are the smartest animals? The animal most often cited are chimps, followed by the other Great Apes (gorillas and orangutans). Jane Goodall, a primatologist famous for her 45-year study of Tanzanian chimp social and family life, made a list of five of the smartest animals:
1. Great Apes, which have learned parts of ASL (American Sign Language), and even taught it to each other. Furthermore, some Great Apes have been able to perform some basic functions on specially-designed computer programs, including solving certain problems involving colored shapes.
2. Whales and dolphins (cetaceans) are probably the smartest animals in the aquatic world. Like humans, cetaceans are capable of creating a mental image of and communicating with their fellows at great distances, using echolocation and special clicking noises. Some of these “songs” can be quite complex, and humans are at a loss to describe what they mean, though what has been uncovered is a testament to the animals’ intelligence.
5. The last on the list of smartest animals are the dogs and cats. To anyone with a dog or cat, their relative intelligence is obvious. They can understand the way a human feels by their facial expressions and tone of voice. Both dogs and cats can be trained to perform complex tasks in numerous ways, even potty-trained, but dogs are clearly more inclined to take orders from humans.
Among the invertebrates , octopuses are often cited as the most intelligent. Pigs are another intelligent group, as are squirrels. Scientists are just beginning to learn the ins and outs of animal intelligence, and much more remains to be learned.