Crows can solve complex puzzles, use tools, and even create tools, something only a few non-human species can do. One famous example is the New Caledonian crow, which has been seen crafting hooks out of twigs to fish insects out of tree bark.
They have incredible memories, especially when it comes to faces. Crows can recognize individual human faces and will remember if you were nice or mean to them. They even teach their young who to trust or avoid. Crows live in tight-knit family groups and communicate using a wide range of vocalizations and gestures. They also engage in something called “social learning”—they learn behaviors by watching others, not just trial and error.
When a crow dies, other crows will gather around it, sometimes in large groups. Researchers think this behavior may be a way for them to learn about dangers in the area. Crows have been observed sliding down snowy rooftops for fun, playing games with other animals, and even playing tricks on each other. Play is often a sign of intelligence in animals.
Science Alert writes “Crows have a sense of geometric intuition much like our own, a new study reveals. They can detect the ‘odd one out’ in a set of geometric shapes, and have an affinity for geometric regularity – shapes with consistent features, like squares, as opposed to irregular ones, like rhombuses.
Crows are the first non-human animals to demonstrate these abilities. This suggests that recognizing geometric shape regularity may be deeply ingrained in evolution, and could be more common in the animal kingdom than we’ve realized.
“We humans – based on our unique formal and symbolic understanding – take geometry to a whole different level; but the very foundation of it, from a visual point of view, seems to be rooted in evolution,” animal physiologist Andreas Nieder told ScienceAlert. Nieder and his colleagues from the University of Tübingen in Germany worked with two male carrion crows ( Corvus corone ), aged 11 and 10 years old, for the experiment.
The crows were trained to detect a single outlier shape that didn’t match the five otherwise identical two-dimensional shapes displayed on a computer screen. To demonstrate which shape they determined to be the ‘intruder’, the crows pecked on its on-screen position.
“Up to this stage of the experiment, the crows had never been tasked with detecting a quadrilateral intruder amid an array of other quadrilaterals,” the authors note in their research paper. This ensured the crows would demonstrate pre-existing geometric sensibilities, rather than learned ones. For the main trials, half the time the crows were shown sets of quadrilaterals that contained varying degrees of regularity, with each shape set to a random rotation and scale.
The crows found it easier to detect an outlier among four-sided shapes with regular features, like the even length of sides in a square, or the consistent 90-degree angles of a rectangle. The more regular the shape’s angles and sides, the more accurate ‘intruder’ detections the crows made.