Determining which animal is the closest to human intelligence is a complex question that involves comparing cognitive abilities, emotions, self-awareness, language use, and more across species. There are many animals that exhibit impressive mental capabilities, but based on research, the top contenders for closest to human intelligence are great apes (chimpanzees, gorillas, orangutans, bonobos), dolphins, elephants, and corvids (crows and ravens).
Cognitive abilities
When looking at cognitive abilities like problem-solving, reasoning, numeracy, tool use, and insight, great apes stand out as the non-human animals most similar to humans. Chimpanzees in particular have demonstrated advanced skills like:
- Using objects as tools to obtain food or water.
- Devising multi-step plans to achieve a goal.
- Making and using complex tools.
- Having episodic memory similar to humans.
- Understanding cause-and-effect relationships.
In experiments, great apes can learn languages consisting of symbols or sign language and use them to communicate with humans. They even combine symbols in meaningful ways to express ideas. Great apes also surpass monkeys in tests of spatial memory, short-term memory, and social reasoning abilities.
Self-awareness
Self-awareness is another benchmark of intelligence that great apes meet at a high level compared to other species. Self-awareness refers to an ability to recognize oneself as an individual separate from the environment and other individuals. Tests of self-awareness include:
- Mirror self-recognition – Being able to recognize one’s reflection in a mirror as oneself.
- Self-agency – Understanding that one’s actions have effects and one has control over one’s body.
- Theory of mind – Understanding that others may have different thoughts, perspectives, and motivations than oneself.
Great apes, dolphins, elephants, and magpies are some animals that pass the mirror test of self-recognition. Great apes also demonstrate theory of mind in their social interactions and cooperative activities. They seem to understand the mental states of others in their group.
Emotions
Research has uncovered surprising emotional complexity in animals like great apes, dolphins, elephants, and corvids. These species show behaviors that suggest emotions like:
- Joy
- Anger
- Grief
- Compassion
- Loneliness
- Frustration
- Determination
Great apes react in ways that seem to convey genuine emotion – laughing when playing, pouting or throwing tantrums when upset, displaying grief at the death of a relative. They also deceive and manipulate in order to gain social advantage, which implies an understanding of other minds.
Social abilities
Highly intelligent animals like great apes, dolphins, and elephants form closely bonded social groups and demonstrate cooperation and altruism. Some examples of advanced social behavior include:
- Coalition forming between individuals for mutual gain.
- Allied groups working together against a common threat.
- Cultural transmission of behaviors and knowledge between generations.
- Reciprocal altruism and empathy.
In great apes, intense sociality and cooperation has driven the evolution of greater intelligence. The need to understand friendships, alliances, motivations, emotions, and communicate within the group selected for more complex cognitive capacities in apes.
Communication
While no animal has syntax and grammar like human languages, some species have vocabularies of calls and an understanding of symbolic communication. Examples include:
- Great apes using sign language or picture symbols to make sentences and communicate with humans.
- Dolphins naming signature whistles for each other.
- Prairie dogs with different warning calls for predators depending on how close and how dangerous they are.
- Bees communicating locations of food sources through complex dances.
The communication systems of prairie dogs and bees seem tailored to narrow purposes. But primates and cetaceans like dolphins may have some level of open-ended understanding that communication symbols represent objects, actions, and concepts beyond just signaling warnings or directions.
Play behavior
Play involves imagination, social bonding, learning, and joy. Intelligent animals like great apes, corvids, octopuses, and dolphins engage in sophisticated play by:
- Pretend playing – acting out imagined scenarios, role playing.
- Playing games with rules – requiring an understanding of turn taking, rewards/penalties, strategy.
- Playing with objects – using toys or manipulating objects as playthings.
- Rough and tumble play – mock fighting while taking cues to avoid real harm.
The ability to pretend requires separating reality from imagination. Games with rules indicate logical thinking, strategy, and mental flexibility. Object and rough and tumble play demonstrates an awareness of self and others.
Observational learning
Imitation is considered a complex cognitive ability. Some animals that skillfully learn by observing others include:
- Great apes – Learning tool use by watching other apes.
- Crows – Picking up innovative food-finding techniques from other crows.
- Octopuses – Mimicking behaviors they observe in others, like turning off light switches.
- Dolphins – Rapidly learning hunting behaviors by observing their mothers.
Mastering new behaviors via observation allows innovations to spread through social groups. It also requires linking observed actions with one’s own understanding and body movements in order to replicate the new skill.
Problem solving and insight
Experiments have shown some species are capable of advanced problem-solving, insight, and creativity. Examples include:
- Chimpanzees rapidly learning to use boxes as step stools to reach bananas hanging from the ceiling.
- Crows bending hooks into straight wires to fish objects out of tubes.
- Elephants working together to problem solve by holding objects with their trunks.
- Octopuses opening screw-top jars after watching humans do it once.
These behaviors go beyond trial-and-error learning to suggest genuine cognitive insight into discovering innovative solutions. Quick individual learning and social transmission of such innovations are hallmarks of general intelligence.
Brain structure and genetics
At a biological level, human and great ape brains share similarities in structure and genetics. Chimpanzee brains are around one third the size of the average human brain. The neocortex region that supports higher cognition is also less developed compared to humans. But in contrast to other mammals, great apes possess:
- Larger frontal lobes (supporting planning, problem solving, emotions).
- More intricate neuronal wiring between different brain regions.
- A brain organization into lobes and hemispheres like the human brain.
Great apes also share over 98% of their DNA with humans, supporting the close evolutionary kinship between humans and apes.
Ranking animal intelligence
Based on cognitive, social, emotional, and communicative behaviors, as well as brain structure, great apes demonstrate intelligence most analogous to humans. A rough ranking of animal intelligence compared to humans is:
- Great apes – chimpanzees, gorillas, orangutans, bonobos
- Dolphins
- Elephants
- Corvids – crows, ravens
- Octopuses
- Parrots
- Dogs
- Pigs
However, intelligence is complex and cannot be neatly measured on a linear scale. Different species have evolved specialized cognitive abilities based on their social structures, environmental challenges, and evolutionary histories. Some animals like prairie dogs and bees display impressive intelligence tailored to specific purposes that exceeds apes in certain domains. Overall, great apes demonstrate the broadest range of general intelligence that is most similar to our own.
Why great ape intelligence is the closest to humans
In summary, great apes, especially chimpanzees, are considered the non-human animals with intelligence closest to humans due to:
- Advanced cognitive skills – problem solving, numeracy, insight, tool use, cause-and-effect reasoning, memory.
- Self-awareness – self-recognition, theory of mind, self-agency.
- Complex emotions – joy, grief, anger, loneliness, determination.
- Social behaviors – alliances, social transmission of knowledge, cooperation, cultural behaviors.
- Some extent of symbolic communication using language-like signing or picture symbols.
- Imaginative and social play activities.
- Observational learning.
- Brain structure similar to humans – large frontal lobes, complex neuronal wiring.
The collective intelligence displayed by groups of great apes, the way knowledge passes between generations, and the sophisticated collaboration between individuals resembles human capabilities in many ways. No other species exhibits mental skills that are as advanced and general as great apes. Their broad cognitive capacity mirrors the open-ended, imaginative, and socially complex minds of humans.
Caveats
There are some caveats to consider when declaring that great apes have intelligence most similar to humans:
- Lack of comparably advanced technology and culture as humans is a key difference. But this may reflect limitations of anatomy, not intelligence per se.
- ape language abilities remain primitive compared to human language.
- Human brains are still 3 times bigger than ape brains.
- Scientists still debate if animals even experience emotions in ways comparable to humans.
- Human-devised tests may underestimate the intelligence of species like crows or octopuses in ways we don’t fully comprehend yet.
Additionally, considering one species “most intelligent” risks missing the unique evolutionary adaptations that make each animal’s intelligence special in different ways. However, when ranking broad general intelligence, great apes demonstrate the most human-like capabilities overall based on current evidence.
Conclusions
Great apes, especially chimpanzees, are the non-human animals considered to have intelligence most similar to human intelligence:
- They have advanced cognitive abilities comparable to young human children in experiments.
- They display self-awareness, theory of mind, and complex emotions.
- Ape social interactions are highly cooperative and culturally transmitted between generations.
- They use communication gestures and symbols in sophisticated ways.
- Great ape brains share key structural similarities with the human brain.
However, great ape language and tool use remain primitive compared to humans. Additionally, the collective intelligence and cultural behaviors of humans still far exceeds that of other species. But research continues to uncover new evidence of the remarkable convergent cognitive evolution between humans and great apes.
