What Is the Smartest Animal? The 10 Smartest Animals

Chimpanzees and bottlenose dolphins are the smartest animals after humans, and the evidence for each is strong enough that scientists rarely try to separate them. Chimpanzees make and use tools, pass local traditions between generations and outperform people on some short-term memory tests. Dolphins recognise themselves in mirrors, use signature whistles that work like names, and learn hunting techniques from their mothers.

Orcas, octopuses, ravens, crows and elephants complete the top tier. The editorial ranking on the AnimalDex smartest animals tier list puts the Dolphin, Chimpanzee and Orca first, ordered by kind of intelligence rather than a single score.

There is no IQ test that works across species. A crow, an octopus and a chimpanzee solve different problems with very different brains, so the most useful answer names the leader for each kind of intelligence: social reasoning, tool use, memory, communication and solitary problem solving.

Smartest animals tier list (top 100)What makes crows so intelligentHow octopus intelligence worksChimpanzee species page

This is the editorial top ten from the AnimalDex smartest animals tier list, in the same order. It mixes mammals, birds and molluscs because intelligence evolved several times independently: in primates, in whales and dolphins, in corvids and parrots, and in octopuses and cuttlefish, whose last common ancestor with us was a simple worm-like animal more than 500 million years ago.

See the full smartest animals tier list

DolphinChimpanzeeOrcaOctopusRavenCrowElephantGorillaCuttlefishWolf

Each top-tier animal has a body of published research behind its place, not just a viral video.

Dolphin: self-recognition and names

In 2001 Diana Reiss and Lori Marino showed in PNAS that bottlenose dolphins use a mirror to inspect marks placed on their bodies, passing the mirror self-recognition test once thought to be limited to great apes. Each dolphin develops a signature whistle early in life, and other dolphins copy it to call that individual. In Shark Bay, Western Australia, some bottlenose dolphins carry marine sponges on their beaks to protect them while they forage on the seabed, a technique passed mostly from mother to daughter.

Chimpanzee: tools and culture

Jane Goodall's 1960 observation of chimpanzees at Gombe fishing for termites with stripped twigs changed the definition of tool use. Chimpanzees in West Africa crack nuts with stone hammers on wooden or stone anvils, and young chimpanzees take years to learn it. A 1999 Nature paper by Andrew Whiten and colleagues compared long-term field sites and identified 39 behaviours, from tool use to grooming styles, that differ between communities in ways best explained by culture. In memory tests in Kyoto, a young chimpanzee named Ayumu recalled the positions of briefly flashed numbers faster and more accurately than the university students tested.

Orca and octopus: two opposite kinds of smart

Orcas live in stable family pods with their own call dialects and hunting traditions: some pods in Antarctica make waves to wash seals off ice floes, and some in Patagonia deliberately strand themselves to grab sea lion pups from the beach. Octopuses show what a solitary, short-lived animal can do. They open jars, escape tanks, and veined octopuses in Indonesia carry coconut shell halves across the seabed to use later as a shelter, which a 2009 Current Biology study described as tool use.

Ravens and crows: primate-level reasoning in a small brain

New Caledonian crows make hooked tools from twigs and cut stepped tools from leaves, reported in Nature in 1996. Ravens in a 2017 Science study chose a tool or a token they would need the next day over an immediate small reward, a level of planning previously shown only in great apes. Bird brains are small, but a 2016 PNAS study found that corvids and parrots pack about twice as many neurons into their forebrains as primates with brains of the same mass.

Elephant: memory and social knowledge

Elephants have the largest brain of any land animal, around 5 kg. An Asian elephant named Happy passed the mirror self-recognition test at the Bronx Zoo (Plotnik and colleagues, PNAS, 2006). In the wild, older matriarchs remember distant water sources and recognise the calls of dozens of other families, and their groups survive droughts better.

The tier list opens with the editorial top ten above. Below them, the table continues by the AnimalDex intelligence stat, a catalog profile score used across every species in the app. It is not a published IQ test. Because that score weighs social group life, problem solving and grasping hands heavily, primates dominate the next rows: the White-faced Capuchin, Woolly Monkey and Red-shanked Douc come right after the top ten.

Monkeys such as capuchins really are strong problem solvers, and some capuchin populations crack nuts and shellfish with stones in the wild. Read the lower rows as the catalog's intelligence stat, and the editorial top ten as the answer to the everyday question of which animal is smartest.

Smartest animals tier listHow orangutans think and survive in the canopy

White-faced CapuchinWoolly MonkeyRed-shanked DoucRing-tailed LemurMandrillBonoboProboscis MonkeyWestern Lowland GorillaJapanese MacaqueNaked Mole-rat

When people ask for the smartest animal they usually mean within a group they know. These are the best-supported answers.

New Caledonian crowAfrican grey parrotHoney beePigHow dolphin intelligence works in the wild

African Grey ParrotHoney BeePigCommon Raven

Researchers test pieces of intelligence rather than the whole. The mirror test, introduced by Gordon Gallup in 1970, checks whether an animal uses a mirror to investigate a mark on its own body; great apes, bottlenose dolphins, Asian elephants and Eurasian magpies have passed versions of it. Other tests look at tool use, causal reasoning (such as dropping stones into a tube to raise the water level), planning, delayed gratification, numbers, and social learning.

Brain measures help but do not decide the question. The encephalisation quotient compares brain size with what would be expected for an animal's body size; neuron counts, especially in the forebrain, turn out to predict ability better than brain weight alone.

• Myth: the biggest brain is the smartest

  The sperm whale has the largest brain of any animal, about 8 kg, but body size, brain structure and neuron density matter more than raw weight. A raven's brain weighs around 15 grams.

• Myth: dogs are the smartest animals

  Dogs are specialists at reading human gestures, better than chimpanzees at following a pointing finger, but they do not lead on tool use, planning or self-recognition.

• Myth: goldfish have a three-second memory

  Goldfish can be trained to respond to cues and remember them for months.

• Myth: one ranking can settle it

  Different tests favour different animals. That is why the tier list gives a top tier and explains which kind of intelligence each animal shows.