You stumble through the desert, desperately seeking water.
You encounter a tall barrel, half-full of water, at the base of a boulder-strewn hillside.
Try as you may, your arms simply cannot reach the life-giving water below. Your fingertips stop inches from the surface.
Time has run out. If you cannot get this water, you will die.
What do you do?
American crows – known to ornithologists as Corvus brachyrhynchos — are moderately large, gregarious birds, who live throughout most of the United States. They even spill over into Canada during the summer breeding season.
Forests, beaches and prairies were the species’ preferred habitats for thousands of years, but modern crows have adapted to their changing world. They now colonize disturbed habitats throughout their range, including farms, neighborhood parks and dense urban areas.
In fact, crows continue to find ways of adapting to the ways these habitats continue to change. Cities in the 21st century are much different than they were only 50 years ago, and the crows have kept up with the times.
As new opportunities, dangers and novelties have appeared, the crows have changed their behavior to suit the new world order.
Their generalist nature and flexible diet have helped the birds to adapt to these new habitats, but their greatest gift is undoubtedly their intelligence – crows are thinking birds.
In fact, they solve problems and draw conclusions about as well as your kindergartner does.
But don’t worry; your kindergartener is probably cuter than a crow.
Crows are visual creatures, just like we are. They primarily collect information about the external world via their sense of sight.
This is fortunate, as it allows us to understand crow intelligence more intuitively than we can the sonar-driven world of dolphins or the odor-oriented lives of dogs.
Take facial recognition, for example. Humans rely heavily on facial recognition to navigate our complex social environment.
Our ability to recognize the faces of other individuals (and read the expressions conveyed) is foundational for our social system. It’s also an area in which humans dominate — few other species are likely to match our talent for recognizing and remembering faces.
But a handful do demonstrate an aptitude for the task.
Chimpanzees, for example, are not only capable of identifying familiar individuals by looking at their faces (they primarily key on the eyes to do so), but they can detect familial similarities in the faces of other chimps. That is, they can tell that two chimps are related by observing their faces.
Given the close kinship we share with chimps, it is unsurprising that our evolutionary cousins (as well as our more distant relatives the apes, and even more distant relatives, the macaques) can also distinguish one face from another, and that they rely heavily on facial clues when communicating.
However, a few non-primate mammals also exhibit this ability. Sheep, it turns out, can do the same thing, as can cows and dogs.
But let’s get back to birds.
Scientists have long known that some birds use visual cues to distinguish between individuals since way back in 1968. More recently, Christopher D. Bird and Nathan J. Emery demonstrated that some birds could visually recognize conspecifics in 2008. I cannot find a study specifically demonstrating that crows have such capabilities, but given the information revealed in subsequent studies, it seems all but guaranteed that they do.
In 2009, University of Washington researcher John M. Marzluff led a team of biologists, who were studying the intelligence and visual abilities of some very bright birds.
Guess what species they focused on.
In the course of their study, the researchers banded the legs of crows in five different populations. However, unlike most similar studies, these researchers wore masks while capturing and banding the birds.
Some of the masks were quite ridiculous looking (think Halloween masks); others were custom molded from real human faces, and they looked relatively normal.
Banding is a common and harmless practice among ornithologists, but the act of trapping and then restraining the bird while adding the band surely causes some acute stress. In general, the banding process results in one very pissed off crow.
You can probably imagine how the crows reacted when these masked ornithologists returned and began observing them from a short distance. Crows usually make their feelings pretty clear.
Irritated or frightened crows engage in a behavior ornithologists term “scolding.” Scolding involves the emission of repeated and loud vocalizations (kaw-kaw-kaw). When other crows join the cause, they are said to be “mobbing”.
When the masked scientists returned, the crows almost invariably began scolding and shrieking at the perceived threats. They even formed mobbing flocks in some of the trials.
But here is the interesting bit: It didn’t matter who wore the mask during the follow-up observations.
By and large, the crows who had associated the mask with a negative experience (the banding procedure) attacked whoever wore it later. This was true regardless of the wearer’s height, weight, gender or gait.
This suggests that the crows were specifically keying on the facial features of the perceived predator, rather than some other physical cue.
The researchers conducted similar experiments in five different locations using a variety of methodologies and multiple controls to help ensure the results spoke specifically to the faces.
But wait, there’s more.
In late 2011, some of the same researchers published a follow-up study (this time led by Heather N. Cornell).
In it, they demonstrated that the crows retained a fear of the masks over the course of several years, and they reliably greeted mask-wearers with scolding behaviors. But even more impressively, crows who were never banded had learned to fear the masks as well.
According to the researchers, this occurred via two different mechanisms.
Some of these crows had become conditioned to fear the masks while engaging in mobbing behaviors with other crows — a phenomenon known as horizontal social learning. Others learned of the danger from a parent, which behaviorists call vertical social learning.
This suggests that crows are not only intelligent but that they are literally becoming wiser each day. They not only learn from their environment — they learn from each other too.
In fact, these clever birds are continually expanding the species’ skill set, and constantly devising new approaches for making their way in a changing world.
Take, for example, these clever crows living in Japan.
I know what you’re thinking: They can’t be doing what they’re doing.
But they are.
These crows figured out that cars could break open nuts. So, they began purposefully dropping nuts on to the road from above. A car would come by and crack open the nut, and the crow would feast.
But every once in a while, a crow would wind up getting hit by a car during the process. This caused the birds to refine their strategy. Now, many have begun dropping nuts on the road near pedestrian crossings.
As before, passing cars smash the nuts, exposing the delicious, high-calorie meals lurking inside. But instead of dropping down to the ground immediately, the crows will wait for the “walk” signal. Once the cars all stop, the crows venture to the ground and retrieve their food in relative safety.
Mind-blowing as it is, this kind of thing isn’t an isolated phenomenon — crows from all over the world are learning to do new and interesting things.
Check out this TED talk by Joshua Klein. Among other interesting pursuits, Klein studies crows. Well, studies and manipulates.
For those who don’t want to watch the video, Klein has taught a group of crows to use a “vending machine.”
A crow drops a token into the designated slot and gets a bit of food for his trouble.
That’s interesting and cute, but the really cool thing is that Klein believes it is possible to train free-living crows to do the same thing with litter. In other words, urban crows could be trained to collect trash, toss it in the machine and earn a little food in return.
I think that harnessing the natural abilities of animals to serve the greater good is fantastic. I doubt we’ll be living in cities kept clean by local crows anytime soon, but it’s fun to think about.
Enough about how smart crows are. Let’s find out how smart you are.
Did you ever figure out how to get the water from the barrel?
The solution is pretty simple, and for some, quite intuitive. Personally, had I not read about this trick as a child, I’d surely die of dehydration.
All you have to do is pick up a couple of those rocks and chuck ‘em into the barrel. They’ll take up room in the barrel, pushing the surface of the water up and within reach of your cupped hands.
Watch these crows demonstrate:
This video was filmed as part of a study led by researcher Sarah A. Jelbert and published in a 2014 issue of PLOS One. In a nutshell, the study sought to investigate causal learning among New Caledonian crows (or, as they call them, Corvus moneduloides).
This particular test is essentially a scaled-up version of one of Aesop’s Fables. In the tale, the bird demonstrates an understanding of water displacement.
Many adult humans find this principle intuitive enough: If you crawl into a bathtub, the water level rises. However, it turns out that crows usually score as well on this test as 5 to 7 year-old-humans do.
All of this is to say that we should pay more attention to the crows around us. They’re intelligent and fascinating animals who offer a variety of lessons for those observant enough to notice. We should do everything we can to learn from them.
It’s only fair.
They are certainly learning from us.