We are figuring out how to evaluate the mind of other living beings and whether it is possible to choose a clear favorite among them.
Strictly speaking, humans are the smartest animals on Earth—at least by human standards. We do a good job with all the tasks that we set as indicators of intelligence, and our entire culture and its many achievements are a product of the mind.
But what about millions of other animal species? How do we evaluate them? Measuring the intelligence of animals can be difficult due to a variety of indicators, including the ability to learn new things, the ability to solve puzzles, the use of tools and self-awareness. Identifying the smartest animals can lead to arguments and some surprises.
Consider an octopus. At first glance, it may not seem very smart, but studies have shown that some cephalopod species have great curiosity and the ability to solve complex problems. In one experiment, an octopus figured out how to unscrew the lid of a container to get a treat inside. In another case, an octopus learned to recognize people by reacting positively to a friendly person and ignoring a person who behaved impersonally. Recognizing people is a sign of intelligence, which is also inherent in pigeons.
We can assume that chimpanzees — one of our closest genetic relatives — will have high scores on our intelligence scale, and so it is. In a 2007 study, scientists gave adult chimpanzees, adolescent chimpanzees, and college students the same cognitive test, which involved memorizing nine numbers on a touch screen, provided that the pictures change each other very quickly. Adult chimpanzees and college students scored about the same, but teenage chimpanzees outperformed everyone, memorizing numerical positions with much higher accuracy.
Goats, like octopuses, have proven their ability to solve difficult tasks, especially when their reward is food. In one trial, goats had to use their teeth to pull a rope down, activating a lever, which they then had to lift with their mouth. A total of 9 out of 12 goats were able to figure out the contraption after four attempts, and most still remembered how to work with the device even after 10 months.
Many animals use tools effectively, including chimpanzees, who use sticks to extract ants and termite larvae. Crows have demonstrated similar abilities, proving in one test that they are smarter than human children. In the test, a cylinder with water was used, at the top of which a reward floated. The cylinder was too thin for the crow to reach it with its beak or for the child to put his hand through (children were not allowed to use thumbs). It was very difficult for children under the age of eight to solve the puzzle, but the crows seemed to know instinctively that adding pebbles to the cylinder would gradually raise the water level until they reached the reward.
Elephants, like many other animals, can learn a lot of complex tasks, but it is their self—awareness — the ability to recognize themselves in a mirror – that distinguishes them on the intelligence scale. (Many other animals, such as dogs and cats, seem to believe that their reflection is another animal, and react accordingly.) Elephants are also very sociable and compassionate, often working together to solve problems in their herd.
Other animals known for their intelligence include pigs, which can traverse mazes and learn symbolic language; rats, which can make decisions based on what they do and what they don’t know; and bottlenose dolphins, which have the same degree of self-awareness as elephants.
So determining which animal is the “smartest” really depends on your criteria. Perhaps the more pressing question is: Do other animals evaluate our intelligence? And if so, do they think we’re the smartest on Earth—or are we just ridiculous primates from their point of view?