How Smart Are Crows? Smarter Than You Think

Crows, ravens, and jays belong to the Corvidae family of birds. Throughout history, people have marveled at the intelligence of these birds. They are so smart, we might find them a bit creepy. It doesn't help that a group of crows is called a "murder," that they are viewed by some as harbingers of death, or that the birds are clever enough to steal trinkets and food. A crow's brain is only about the size of a human thumb, so how smart are crows, really?

As Smart as a 7-Year-Old Child
While a crow's brain may seem small in comparison to a human brain, what matters is the size of the brain in relation to the size of the animal. Relative to its body, a crow's brain and a primate brain are comparable. According to Professor John Marzluff at the University of Washington's Aviation Conservation Lab, a crow is essentially a flying monkey. Whether it's a friendly monkey or more like a fiend from "The Wizard of Oz" depends a lot on what you've done to the crow (or any of its friends).

They Recognize Human Faces
Can you tell one crow from another? In this respect, a crow may be smarter than you because it can recognize individual human faces. Marzluff's team captured crows, tagged them, and released them. Members of the team wore different masks. Crows would dive-bomb and scold people wearing a mask, but only if the mask had been worn by someone who had messed with them.

They Talk About You to Other Crows
If you think two crows watching you and cawing at each other are talking about you, you're probably right. In Marzluff's study, even crows that were never captured attacked scientists. How did the crows describe their attackers to other crows? Crow communication is poorly understood. The intensity, rhythm, and duration of caws seems to form the basis of a possible language.

They Remember What You Did
It turns out crows can pass on a grudge to their offspring — even subsequent generations of crows harassed masked scientists. So if you're wondering just how smart crows are... you may find this one disturbing.

Another case of crow memory comes from Chatham, Ontario. Around half a million crows would stop in Chatham on their migration route, posing a threat to the farming community's crops. The mayor of the town declared war on crows and the hunt began. Since then, the crows have bypassed Chatham, flying high enough to avoid being shot. This had not, however, stopped them from leaving droppings all over the municipality.

They Use Tools and Solve Problems
While several species use tools, crows are the only non-primates that make new tools. In addition to using sticks as spears and hooks, crows will bend wire to make tools, even if they have never encountered wire before.

In Aesop's fable of "The Crow and the Pitcher", a thirsty crow drops stones into a water pitcher to raise the water level to take a drink. Scientists tested whether crows really are this smart. They placed a floating treat in a deep tube. The crows in the test dropped dense objects into the water until the treat floated within reach. They didn't select objects that would float in the water, nor did they choose ones that were too large for the container. Human children gain this understanding of volume displacement around the ages of five to seven.

Crows Plan for the Future
Planning for the future isn't only a human trait. For example, squirrels cache nuts to store food for lean times. Crows not only plan for future events but consider the thinking of other crows. When a crow caches food, it looks around to see if it's being observed. If it sees another animal is watching, the crow will pretend to hide its treasure, but will really stash it in its feathers. The crow then flies away to find a new secret spot. If a crow sees another crow hiding its prize, it knows about this little game of bait-and-switch and won't be fooled. Instead, it will follow the first crow to discover its new hoard.

They Adapt to New Situations
Crows have adapted to life in a human-dominated world. They watch what we do and learn from us. Crows have been seen to drop nuts in traffic lanes so the cars will crack them open. They will even watch traffic lights, only retrieving the nut when the crosswalk sign is lit. This in itself makes the crow smarter than most pedestrians. Crows have been known to memorize restaurant schedules and garbage days, to take advantage of prime scavenging times.

They Understand Analogies
Do you remember the "analogy" section of the SAT? While a crow is unlikely to outscore you on a standardized test, they understand abstract concepts, including analogies. Ed Wasserman and his Moscow-based team trained crows to match items that were the same as each other (same color, same shape, or same number). Next, the birds were tested to see if they could match objects that had the same relationship to each other. For example, a circle and a square would be analogous to red and green rather than to two oranges. The crows grasped the concept the first time, without any training in the concept of "same and different."

They Can Outsmart Your Pets
Cats and dogs can solve relatively complex problems, but they can't make and use tools. In this respect, a crow is smarter than Fido and Fluffy. If your pet is a parrot, its intelligence is as sophisticated as a crow's. Yet, intelligence is complicated to measure. Parrots have curved beaks, so it's harder for them to use tools. Similarly, dogs don't use tools but have adapted to work with humans to get their needs met. Cats have mastered humanity to the point of being worshiped. Which species would you say is the smartest?

Modern scientists recognize it's practically impossible to apply an intelligence test across different species because an animal's skill at problem-solving, memory, and awareness depends on its body shape and habitat as much as on its brain. Yet, even by the same standards used to measure human intelligence, crows are super smart.