In language research, the scientific attempt to teach other animals than humans something of the human language, our hairy cousins the great apes have been studied in particular. Already at the beginning of the last century did scientists attempt to teach chimpanzees to pronounce human spoken words, after which one started teaching signs to great apes from the sixties onwards, and from the seventies onwards by using geometric symbols or lexigrams. Also since the seventies, dolphins, sealions and parrots have been studied in language research. In the past few years, however, there have been several interesting studies with dogs. Everyone who sometimes relates to a dog, knows that most dogs can react to commands like “sit” and “stay”. In these recent studies it has been demonstrated that some dogs can understand hundreds of human words.
Border collies
The dogs I’m talking about are border collies. 
In the history of the human domestication of dogs, the border collies have been selected for their ability to herd cattle, in particular sheep. They originate in the border area between England and Scotland (therefore the name ‘border’). They have los of energie, show great speed and agility and are used in all kinds of dog sports. And they’re very intelligent. In the classification by Stanley Coren the border collie is supposed to be the most intelligent dog (followed by the poodle and the German shepherd).
Research by Juliane Kaminski
Early 2000s Juliane Kaminski, doctor in psychology at the Department of Developmental and Comparative Psychology of the Max Planck Institute for Evolutionary Anthropology at Leipizg University in Germany, heard about a border collie named Rico, who could understand up to 200 human words for toy objects. The woman who took care of him, Susanne Baus, had started learning Rico words when he was 10 months old and had to recover from an operation and couldn’t be left of the leash outside. She showed him a toy, like a stuffed animal, a ball, told him what the word for it was and by repeating this often enough, the woman could eventually ask Rico to bring the object in various rooms of the house. Kaminski was very interested and set up a good study to find out if Rico truly understood the words.
Clever Hans
In order to do so, the Clever Hans effect had to be prevented. This term in science stands for the presence of human cues that can explain a seemingly intelligent behaviour of an animal. 
It is named after the horse Kluger Hans in Germany, who at the beginning of the last century was famous as a miracle horse. Hans could count, subtract and multiply, tell time, spell out words and more, by tapping his hoof or moving his head. The German psychologist Oskar Pfungst subsequently investigated the horse and he came to the conclusion that the horse was very good in reading the body language of the humans who stood around him. At first the humans would often watch in a tense way when he had been given a question, and when Hans had reached the right number with his hoof, the humans would relax, thereby giving Hans a signal that he should stop tapping his hoof. Maybe Rico was observing his human companion in a similar way and had he not learned words for objects, but was following unconscious human cues.
Rico understands 200 words, Betsy 340
To prevent the Clever Hans effect, Kaminski set up her study as follows. The researcher was in one room together with Rico and Susanne Baus, the woman who took care of him. Before that, Kaminski had put ten objects in a random order on the floor of another room. Baus then had to ask Rico to bring an object, without being able to see the objects and without knowing in what order Kaminski had put them in the other room. Rico went to the other room and fetched the objects correctly. Rico thus had not been able to use human cues to find the right object and had to have an understanding that the human words referred to the objects. After these first 10 objects, the procedure was repeated with another 10 objects and so on. Eventually Rico was able to understand 200 human words for objects. Words like Banane, BigMac, Weihnachtsmann, Hund, Kamel and Zitrone. Kaminski published her study in 2004 in Science and Rico became famous as the dog who understands hundreds of human words. Shortly after that, Kaminski heard of a border collie in Austria, Betsy, who also could understand words and she determined that she could even understand more than 340 human words. Below you see a short film from a BBC documentary about dogs, in which you see Rico and Betsy (in the last few minutes of the film).
Chaser: 1,022 words!
Early this year John Pilley and Allison Reid, two psychologists from Wofford College in South Carolina (USA) published a study with the border collie Chaser in Behavioural Processes. When Kaminski published her work with Rico in 2004, Pilley became intrigued by the question how mány words a border collie is able to comprehend. He got Chaser when she was 8 weeks old and when she was 5 months old he started training her for three years, training Cahser for 4 to 5 hours a day in learning words for objects (the psychology professor Pilley was enjoying his retirement and so had the time for this). Just like the woman who had taught Rico words, Pilley showed Chaser an object, said “This is a …” and repeated this many times a day until Chaser would correctly bring the object. Pilley interspersed this intensive training with lots of loving attention and play with Chaser. In the eventual test of Chaser’s knowledge, care was taken again to prevent unconscious human cueing, by having the objects spread out in another room. Eventually, Chaser demonstrated comprehension of the high number of 1,022 different words for all kinds of toys, many stuffed animals and puppets in all kinds of sizes, balls and frisbees and various kinds of plastic toys. Pilley even went one step further and taught Chaser also the words toy, ball and frisbee. These are not individual names of objects, but categories of objects. Chaser successfully fetched toys if she was asked for that (in a setup with 8 toys and 8 non-toys), and similarly was able to bring balls or frisbees. For balls and frisbees Chaser is able to understand three different labels for an object: its individual name, if it’s a toy or not, and if it’s a ball or a frisbee. Click here for a YouTube film of Pilley and Chaser, in which Chaser shows her understanding of the word ball.
Border collies are thus capable of understanding hundreds of human words and are in that sense comparable to the great apes. In particular of the bonobo Kanzi it has been demonstrated by Sue Savage-Rumbaugh that he could understand hundreds of human words for objects and actions. Border collies are clever, intelligent dogs who have been selected by humans for their ability to cooperate and communicate with humans, which may also to some extent explain their abilities in these studies with words.
The search for the Dutch Chaser
Of course I am very curious to know whether there are border collies in The Netherlands who can understand many human words. If so, I am planning on replicating Kaminski’s studie with a Dutch border collie. If you have a border collie who understands many words, or know someone else with such a dog, please contact me!
References
- Stanley Coren. (1993). The intelligence of dogs. Free Press.
- Juliane Kaminski, Josep Call & Juliane Fischer. (2004). Word learning in a domestic dog: Evidence for fast mapping. Science, 304, 1682-1683.
- John Pilley & Alliston Reid. (2011). Border collie comprehends object names as verbal referents. Behavioural Processes, 86, 184-195.
- E. Sue Savage-Rumbaugh, Jeannine Murphy, Rose A. Sevcik, Karen E. Brakke, Shelly L. Williams & Duane M. Rumbaugh. (1993). Language comprehension in ape and child. Monographs of the Society for Research in Child Development, 58, (3-4, Serial No. 233).
Border Collie fans, this is interesting info for you!