By Sophie Teall
Science experiments do not get much more fun than playing with puppies – especially when there are almost 400 of them. Through the study of puppies, a team from the Arizona Canine Cognition Centre have been able to learn more about dogs’ ability to understand human body language.
Human cognition and body language is special in how it allows for effective, flexible, and cooperative communication. Cooperative communication allows for groups of people to work together to share ideas and achieve a single goal. Children are sensitive to this kind of communication early on, and it turns out that dogs are too. While other animals struggle to understand forms of visual communication from humans, such as pointing, dogs appear to understand it from a very young age. The question then is whether this understanding is something that dogs are born with or learn early on in their development.
The team from the Arizona Canine Cognition Centre aimed to answer this question by looking at 375 eight-week old Labrador or Golden Retriever puppies. At such a young age, they would have had minimal experience with people,so any understanding of human body language would be innate rather than learnt. The puppies underwent three tests.
Firstly, their ability to understand human pointing was tested. The puppies were presented with two overturned cups, and the experimenter pointed at one which contained a treat. In two thirds of the trials, the correct cup was identified, similar to the levels observed in adult dogs. This success rate was higher than would have been expected by chance alone, and puppies did not get better with additional trials. This indicates that the puppies had an innate understanding that if something is pointed at, they should investigate it.
The second experiment aimed to look at how long puppies maintained eye contact with people. For many mammals, eye contact is rare and often seen as threatening. Yet, it forms an important part of social interaction in humans. When puppies were exposed to 30 seconds of high-pitched “puppy-talk”, they would spend six seconds maintaining eye contact with the speaker on average. As grey wolves do not use eye contact in a social way, this suggests that domesticated dogs have been selected to use this form of interaction with people.
The final experiment involved teaching the puppies to find food in a plastic container. Once they had learnt that the container held food, it was sealed with a lid that the puppies could not remove without human help. When this experiment was done with adult dogs, they would quickly look to humans for help, suggesting an understanding of the use of communication to ask others to help achieve a goal. However, the puppies rarely looked up at their handler. This suggests that at this age, they do not yet know that they can ask humans for help.
Dogs have an innate ability to understand human social behaviour, meaning that these results are likely a reflection of the selective breeding process that the dogs have undergone. Domestic dogs are drastically different from their wild ancestors as a result of dogs with certain desirable traits being bred together, so that over generations these traits became more prominent and common. While this is more obvious in the wide range of shapes and sizes in different dog breeds, it is also true for the selection of certain behavioural traits. The study suggests that this includes an understanding of human cooperative communication. This is further supported by the fact that 43% of variance in performance could be explained by genetics at, a level of heritability similar to IQ in people.
In combination, the findings of this study shine a fascinating light on dogs’ abilities to understand human body language. It appears that while puppies have an innate understanding of human social behaviours like pointing and eye contact, the ability to use these behaviours to get help from humans comes later in life, potentially as a result of learning. However, the authors of the study note that it would be interesting to replicate this study on other dog breeds. Golden Retrievers and Labradors are amiable breeds used as service dogs, so sociability is an especially important trait that has been selected for in these breeds. An interesting question to ask next is whether the high levels of understanding of human behaviour could be seen in other breeds selectively chosen to have other traits.