Chaser, known to some as “the world’s smartest dog,” died on Tuesday, July 23, 2019 at the age of 15. The late John Pilley, formerly a psychologist at Wofford College, trained Chaser to tend a “herd” made up of more than 1,000 toys and remember the name of each item in the pile. In 2009, NOVA visited Chaser to test her vocabulary.
The World's Smartest Dog
Published August 15, 2018
Onscreen: How did this dog get so smart?
Neil DeGrasse Tyson: John Pilley, a chipper 82-year-old, started working with dogs as a psychology professor.
John W. Pilley: Walk up. Walk up. Walk up.
Tyson: Now he’s got one of the smartest dogs around.
Pilley: Come on. Come on.
Tyson: And I’ve come to check out what she can do.
Pilley: Good girl.
Tyson: Chaser is a six-year-old female border collie, a breed famously skilled at herding sheep.
Pilley: She was born to live in the Scottish mountains…
…and herd sheep…
Go, go, go.
…be a shepherd.
Tyson: John has taught Chaser to tend an extremely large “herd,” but there are no real sheep in it. Chaser’s herd is made up of toys, about a thousand of them.
And she knows the name of every single one of these?
Pilley: I hope.
John has assigned a name to each one…
…and taught those names to Chaser.
Pilley: She has about 12 elephants.
Tyson: Apparently, sometimes John ran out of stuffed animals.
Pilley: Uh oh, these are a pair of my shorts.
Tyson: Oh, my…
Pilley: No, no, that’s one of her toys.
Tyson: John claims that Chaser remembers the name of every single object in the pile. Personally, I find that hard to believe. I don’t have time to test Chaser’s memory on a thousand names, but I will test her on a random sample. John and Chaser go into the house so they can’t see.
So, I’m going to get a handful of toys out of this pile and see if Chaser can identify them indoors.
With John and Chaser out of the room, I lay some of the toys out behind the couch…Inky, there’s Lover
Now it’s time to see if Chaser really remembers their names.
All ready for Chaser.
Pilley: Come, Chaser! Come to Neil.
Tyson: Okay, come on now.
Chaser, find Inky.
Well, she got one right.
Whoa, and that one, too!
Now you might be wondering what’s going on behind the couch, like, “Is John handing her the toys?”
Let’s check our hidden camera.
I asked Chaser to find nine toys, and she got every single one right. And remember, I picked the toys randomly from this huge pile. Neither John nor Chaser saw which ones I picked.
On multiple trials with John and others, Chaser consistently aces her test.
There’s a thousand toys here. That doesn’t, like, spook you?
Pilley: It makes me happy.
Tyson: Let’s see what she does when we challenge her with a new toy she’s never seen or heard the name of.
I smuggled this into your house. It’s a Charles Darwin doll.
Okay, so I put seven toys behind the couch, plus Darwin. Chaser’s never seen Darwin, hasn’t even ever heard the name “Darwin.” So we’re going to see if she picks out Darwin by inference. That’s what we’re going to check.
I’m going to call her down now.
Chaser! Come on back! Let’s have some more fun.
First, I’m going ask Chaser to find a couple of toys she already knows.
Excellent, Chaser! Okay, put him to bed.
Excellent, excellent, good job! Okay, put it in the tub, put it in the tub.
Okay, here it comes, a name she’s never heard before.
So, while searching for the other toys, Chaser knew exactly which one to pick up right away. Now, she seems to have think about which one might be Darwin.
It’s taking her longer.
She takes so long, I call her back.
Chaser? Find Darwin. Find Darwin.
Finally, she makes a choice.
Darwin! You got Darwin!
I can’t believe it. Chaser’s never seen that doll before.
Darwin! You got Darwin! Good girl.
Yet somehow, she made the connection that the name she’d never heard before…
You found Darwin.
…went with the one toy she didn’t recognize.
Chaser’s not the only dog to do this.
And what’s more, dogs like Chaser have shown that they will remember the connection they made between new name and new toy.
This is yet another way they can learn.
Brain Hare: What’s interesting about seeing how dogs are learning these new words is that people thought this was really unique to humans, that this was something that was…only humans do this. But it seems that, no, that’s not the case, that dogs can make these inferences about what novel utterances mean, and they can remember them for quite a long period. Now, this looks just like what little children are doing.
PRODUCTION CREDITS Digital Producer Arlo Perez Editorial Review Julia Cort © WGBH Educational Foundation 2018 MEDIA CREDITS Music APM