25 July 2023

Scientists say that the smartest animals have large brains and have become so intelligent because their lifestyles force them to solve complex ecological (ex: food, habitat) and social problems (ex: long-term social bonds that may include absences).

Ravens and crows both have large brains relative to their body size and both are good at problem solving. The Raven Diaries (@theravendiaries) takes a look at which species acts smarter and why.

So which one is smarter? It’s a hard call between crows and ravens.

Crows understand the concept of zero and know that 0 precedes 1, a feat that beats small humans.

Ravens were tested against chimps and came up equally intelligent: Young Ravens Rival Adult Chimps in a Big Test of General Intelligence. They were also equal if not better at “theory of mind,” the ability to imagine what others are thinking: Ravens have paranoid, abstract thoughts about other minds.

For example, this video shows two ravens guessing what the other is thinking and act accordingly.

Kaeli Swift of Corvid Research is often asked if ravens are smarter than [you-name-it] animal. Here’s the long answer.

(credits are in the captions)

19 December 2022

Pittsburgh’s Christmas Bird Count is only 12 days away on 31 December 2022 so my search for Pittsburgh’s winter crow roost has taken on some urgency. I need to find their roost and a good vantage point for counting them, all before New Year’s Eve. Please let me know where you see crows overnight or after sunset, especially next week (after Christmas)!

Several of you responded to my 5 December blog, Help Me Find Pittsburgh’s Winter Crows, with these helpful dates and locations.

• mid-November: On the Cardello Building near the West End Bridge
• Dec 8 & 9: Flying over Mt. Oliver/Allentown just before dawn
• Dec 11 and 14: roosting at City View, PPG Paints Arena and Cambria Hotel area
• Dec 14: Big flocks flying east to west over Kennard Playground as viewed from Elmore St

I’ve checked from City View to the Hill District but haven’t made it to Mt. Oliver/Allentown yet. This map includes your sightings in orange and mine in yellow.

If I’ve learned anything it’s that the crows keep moving their roost, sometimes rather far. They’ve already abandoned the PPG Paints Arena area and have nudged their Hill District roost further north. Where will they be 12 days from now?

The other mystery is that I’ve only seen 5,000 of them. Does Pittsburgh have 10,000 to 20,000 crows as we did in years past? Where are the other 5,000 to 15,000?

Please let me know where you see crows overnight or after sunset. I’ll be out of town over Christmas and am going to miss the next crow move (they will change location when it’s only 7 degrees on Fri & Sat nights). Your help is really crucial.

I hope to count 10,000 to 20,000 crows on New Year’s Eve.

(and yes, I need to check Mt. Oliver/Allentown!)

(photo by Kate St. John, annotated map screenshot from Google Maps, click on the caption to see the original)

6 December 2022

We humans used to think we were very special and very smart because we had language while other species did not. When we learned that other animals had language too our hubris diminished slightly but we still believed in our uniqueness: We were the only species that could think recursively.

In The Recursive Mind (Princeton University Press, 2011) Michael C. Corballis describes “a groundbreaking theory of what makes the human mind unique.”

The Recursive Mind challenges the commonly held notion that language is what makes us uniquely human. In this compelling book, Michael Corballis argues that what distinguishes us in the animal kingdom is our capacity for recursion: the ability to embed our thoughts within other thoughts. “I think, therefore I am,” is an example of recursive thought, because the thinker has inserted himself into his thought. Recursion enables us to conceive of our own minds and the minds of others. It also gives us the power of mental “time travel”—the ability to insert past experiences, or imagined future ones, into present consciousness.

— Princeton University Press Book description: The Recursive Mind

Our uniqueness suffered another blow last month when a study published in Science Advances revealed that crows can think recursively, too.

What is recursive thinking and how did crows prove they can do it?

Recursive thinking means “embedding thoughts within other thoughts” like nested Russian dolls.

For instance, my sentences are often recursive. If you put parentheses around the complete embedded thoughts they can be thrown away without hurting the sentence. As in: “Our uniqueness suffered another blow last month when a study (published in Science Advances) revealed that crows can think recursively, too.”

To test the birds researchers trained two crows to peck pairs of brackets in a center-embedded recursive sequence. They used differently shaped brackets, some in proper order, some not. Like this:

[ { () } ] or { ( [ ) } ]

The brackets make my head hurt. It’s easier to see in this diagram.

If you put brackets around the starting and ending “thoughts” you’ll see a pattern. The brackets fail in the non-recursive example.

According to Scientific American, after the crows were trained to peck bracket pairs, the researchers tested the birds’ ability to spontaneously generate recursive sequences on a new set of symbols. The birds were successful about 40 percent of the time, on par with 3 to 4 year olds in a 2020 study. The crows were better than monkeys who needed extra training to reach that level.

So another unique human trait is toppled by Corvids.

Hooray for crows and ravens!

p.s. Not all the scientists agreed with the study’s conclusions. Read more at Scientific American: Crows Perform Yet Another Skill Once Thought Distinctively Human.

(photos from Wikimedia Commons, diagrams by Kate St. John. Click on the caption links to see the originals)