Researchers don’t agree on a single, clear definition of intelligence or how to measure it, so it’s hard to come up with a list of the smartest animals on the planet that everyone can agree on.
All living things, including people, have gotten smarter so that they can do well in their natural environment.
For people, we use a wide range of indicators of knowledge, such as self-awareness, creativity, dynamic reasoning, collaboration, generosity, critical thinking, math skills, social learning, language skills, and relationship skills, among others.
Most of the time, when researchers try to figure out how smart a creature is, they look at similar markers. This could be a bad thing because it depends a lot on tests made by humans.
Incredible gorillas, with their use of tools and social skills, make it easy to see human-like signs of intelligence. However, a wide range of non-primate species has also been seen to show signs of intelligence.
Estimating animal intelligence can be risky, and comparing knowledge across a group of animals is a difficult task because tests are usually made for one specific animal species and are hard to use reliably with other species.
Keeping this in mind, we’ve put together a list of 15 of the smartest animals (besides people) in order of their general intelligence.

Racoon
Raccoons are often overlooked when people talk about the smartest animals, but they are famous for being able to pick locks and remember answers for a long time.
In an experiment, analysts at the University of Wyoming gave raccoons a few rocks and a container of water with marshmallows in it. Most of the raccoons figured out that they could put stones in the container to raise the water level and get the marshmallows. That is mature critical thinking that would make a young person smarter.

Gray parrot
Parrots are known for solving puzzles and repeating words that people say, but tests have shown that sometimes they understand what the words mean.
A therapist at Harvard worked with an African dark parrot named Alex to help him understand tones, shapes, and more than 100 English words.

Pigeon
Many people find these birds annoying, and they can be found in most big cities around the world. However, they are beautiful. Because they are everywhere, they have been used in a lot of long-term insight tests, where they have done surprisingly well.
Pigeons have been said to be able to tell the difference between objects and pictures, recognise a single human face, and to be able to see themselves in a mirror.
It’s possible that the pigeon is a very smart bird, or that it’s just a normal bird that’s been looked at too much. In any case, they clearly have a lot of skills that we would call “smart” in other species.

Squirrel
Landscapers all over the world hate squirrels because they are persistent, remember things, and are smart. They are basically forest animals, but they have learned to live near people. They use a variety of ways to get food from bird feeders and any other food they can find a way to get to.
Some California squirrels have been seen covering their fur with diamondback scents to hide their own smell from hunters. Also, when squirrels store food for the winter, they sometimes hide it in a complicated way to confuse people who might try to steal it, which is another sign that they have a smart mind.

Rat
The much-hated rodent is used a lot in research labs and has been the subject of countless insight tests. These very smart rodents are typical students who do very well at learning and getting ideas. Even though they are much smaller than dogs, they seem to be just as good at taking care of things.
Even though rodents can’t see very well, they are great at figuring out labyrinths, and once they learn how to get through one, they never forget it. Also, like many other smart animals, rodents are very kind.
One study found that most rodents tried to help another rodent who was being forced to stay afloat if they had the chance to get a treat.

Octopus
Most of the species on this list of the smartest animals are vertebrates, which means they have spines. However, there are some amazing smart animals that don’t have spines. Not only does the octopus have the largest brain of any invertebrate and human-like features like folded flaps, but 60% of its neurones are in its arms.
Octopi are known to use tools, like one kept in an aquarium that shakes and splashes water at the lights above to break them, and another that collects broken coconut shells to use as security. Some other signs of intelligence are being able to unscrew the top of a bottle and quickly find their way through a maze.

Pig
Pigs are probably the smartest animals that can be tamed. They have many traits that show they are smart. They can figure out how to get out of labyrinths, show and get feelings, and deal with the idea of reflection at a younger age than people can.
Pigs can also understand different portrayals and use this skill to do things like play computer games. In fact, in some tests with video screens, pigs moved as quickly as chimpanzees. One more sign that they knew what they were doing is that the pigs could outcompete the local species wherever they were taken.

Crow
Corvid birds, which include jaybirds, ravens, jays, and crows, are very smart. The crow is an important member of this family. Crows are the only birds (or other non-primate vertebrates) that are known to make tools.
They make traps and tests out of sticks and leaf stems and stick them into the crowns of palm trees. Young birds can make tools, but they get better at it by watching and copying their parents, which is a sure sign of a high animal IQ. Researchers agree that New Caledonian crows are the smartest birds.
This is partly because young crows stay with their parents instead of going off on their own, which gives them more time to develop their mental skills.
Some people say they have the reasoning skills of a 5- to 7-year-old human, which drives them to control their environment. For example, they drop nuts on the street so that cars can break the shells so can eat the nuts.
When you combine this with the fact that they can recognise human faces and communicate complex ideas, it’s easy to see why crows are thought to be the smartest birds.

Elephant
One way to measure knowledge is to compare the size of the brain to the size of the body. The elephant has the biggest brain of any land animal, with the same number of neurones as a human brain.
Elephants are known to have great memories, seem to be capable of extreme kindness, and are aware enough to see themselves in a mirror. They are also able to work together to solve puzzles. For example, in one puzzle, two elephants have to pull different ropes as one to get to two food bowls.

Dolphin
Dolphins and whales are at least as smart as birds and primates, and their brains are about the same size as their bodies. Even so, the dolphin’s brain has more folds than a human’s, which could mean they have more knowledge.
Dolphins and whales are the only marine animals that do well on the mirror test of mindfulness. They are also very friendly and have a good sense of who their friends are. Also, like other very smart species, they use tools, like using wipes to clean their noses when they are looking for food on the ocean floor.
Many researchers agree that dolphins snap, and it’s possible that whistles are just a new way for dolphins to talk. Like many of the most intelligent animals on Earth, young dolphins stay close to their mothers for a long time to learn how to do many things.
Orangutan
Orangutans are probably the smartest animals after people. They have a lot of common sense. Like chimpanzees, they live in their own groups and have been seen using a variety of sophisticated tools in the wild. Like gorillas, they build elaborate sleeping places out of branches and leaves every night.
Orangutans live mostly alone in networks that are spread out, and they build strong but distant social bonds. One study found that they use “determined correspondence” to figure out the costs and benefits of gift trades and keep track of them over time. This is the first time this behaviour has been seen in a species other than humans.

Chimpanzee
Since chimpanzees are our closest living relatives and share 99% of their DNA with us, it’s not too surprising that they are the smartest animal on this list. Their insight is shown from many different angles that cover human abilities. For example, they can make and use tools, hunt together, communicate with gestures, and show selflessness, compassion, and awareness.
Chimpanzee groups build their own societies, with their own unique habits and ways of doing things that they learn or copy from other groups and are able to communicate well. In the wild, they use more than 60 gestures to talk to each other. When they are locked up, they can learn how humans use gestures to talk.
If that wasn’t enough, there have been memory tests where chimps did better than people… So, are humans or chimpanzees the smartest animals on the planet?