Crows Estimated to Have an IQ Equivalent to a 7-Year-Old

Scientists have not administered formal IQ tests to crows. But based on extensive research into corvid cognition over the past 20 years, the average crow IQ matches a 7-year-old human child.

Not your average bird brain! This article dives deep into the science to explain crow intelligence.

Evaluating Crow IQ and Brainpower

IQ, or intelligence quotient, is tricky to measure outside of humans. Still, scientists have assessed sophisticated animal cognition using brain imaging and behavioral tests.

Crows demonstrate complex skill sets well beyond most mammals, let alone small-brained birds. Their reasoning and analytical abilities in particular indicate a higher order of intelligence associated with large brain size and advanced neurology.

Crows perform as well as great apes and human children on some intelligence tests – image credit AAAS/Science

Based on the encephalization quotient relating brain mass to body size, crows rate a 1-1.71. Comparable mammals score:

Like the primate family tree, increased encephalization indicates more complex cognition across crow generations:

Corvid family tree showing growth of brain size and cognition over time – image credit Alexis Breen

In both absolute and proportional terms, corvid brains grew remarkably as species emerged over 25 million years.

The large brain-to-body ratios in modern crows underlie complex information processing and analytical skills at least equivalent to most mammals. Hence the 7-year-old human IQ comparison.

Crow Brain Structure and Next-Level Capabilities

Advanced intelligence requires advanced neurobiology. Let‘s discuss key crow brain features enabling their smarts:

Nidopallium Caudolaterale

This structure packs over 1 billion densely concentrated neurons in crows. For reference, old estimates placed humans at ~86 billion total neurons. But we are MUCH bigger animals.

The NCC governs:

• Working memory
• Multi-step planning
• Problem decomposition

It lets crows hold mental representations to compare options and deduce causality across time and space.

Hyperpallium

The hyperpallium handles sophisticated visual processing in crows.

• Enables storing detailed mental images
• Quick recall of thousands of faces/patterns
• Lightning fast pattern recognition and novelty detection

Thus crows can identify dangerous humans even years later. Or spot minor food changes indicating toxicity.

With these advanced brains supporting exceptional cognition, crows display many behaviors we once considered "uniquely human"…

Crow Behaviors Reflecting Extreme Intelligence

• Manufacture tools – naturally shape sticks and leaves into hooks to probe holes and lift containers
  • Selectively transport best "artifacts" across habitats
• Insight learning – instantly deduce solutions without explicit conditioning
  • Displace water levels to access floating food
  • Use gesture cues from human trainers
• Planning ahead – hide surplus food across caches for future needs
• Language-like communication – evidence of syntactic structures in crow calls
• Observational learning – replicate novel solutions from peers only witnessed once
• Self-recognition – identify own reflection; sense of self
• Hold grudges – convey scoldings/warnings if specific humans threaten nests
• Play games – wrestle ritualistically with clutch-mates and toys

These examples demonstrate intelligence at least matching the great apes studied by pioneering researchers like Jane Goodall.

Chimpanzee mastery of sign language captivated science. Yet pigeons comfortably match or outperform chimps on key markers of abstract reasoning like Raven‘s Progressive Matrices.

Ravens beat chimps on some social coordination tests too. And parrots classify colors/shapes and count items as well as 3-5 year-old humans.

Again, quantitative IQ measures can‘t fully capture corvid cognition. But no credible scientist disputes crow intelligence ranks with the most elite non-human animals.

Why So Smart? The Evolutionary Edge

Of course massive brains consume major energy. Why invest limited resources unless high intelligence confers survival advantages?

For crows, superior brainpower improves:

• Adaptability – flexibly transition across habitats and food fluctuation
• Safety – identify dangerous entities; swiftly escape predators
• Social bonds – navigate complex communities and peer relationships
• Parenting – teach young progressively more complex skills

With crows living 70+ years, accumulated wisdom transfers down generations. Considered another cognitive hallmark of "higher" intelligences.

Smart crows also thrive around humans in modern mega-cities. Unlike most wildlife.

• Scavenge our calorie-dense waste streams
• Opportunistically steal picnic baskets like Yogi Bear
• Even wield cars to crack tough nuts by road lanes!

Our species clearly finds kinship with these plucky avian tricksters.

Perhaps we see our own ingenuty reflected back at us. If so, the mirror suggests hidden depths left to plumb in corvid cognition.