An answer from Dr. Josep Call:
Dear Olivia,
Thank very much for your inquiry, which touches on a crucial topic in the area of Animal Cognition.
There is no question that dogs remember several aspects of their daily lives including things like the places where they go (e.g., the park) and the routes that they take to get there (e.g., by the lake rather than across the woods), the activities that they engage in (e.g., playing catch), the objects that they use for those activities (e.g., Frisbee) as well as the people that share those activities with them. Without memory not only those activities would be vastly impaired, but even some more basic things like recognizing familiar smells and people or learning new things would be impossible for dogs.
Memory plays such a crucial role in our mental lives as well as those of our furry best friends that it should not come as a surprise that memory was one of the first aspects of animal cognition that was investigated by scientists at the beginning of the 20th century. One hundred years of research have taught us much about animal memory including what types of memory exist, how long they last, where they are stored, and what can enhance them or impair them. However, there is still much that we do not know about animal memories, and for some species such as dogs, we know very, very little since they are extremely under-studied from a scientific point of view. Although a bit disappointing from my perspective because I would like to know much more about dog memory, this state of affairs presents dog owners with a terrific opportunity to potentially contribute to advancing our scientific knowledge in this area by reporting their dogs’ performance in controlled tests.
Indeed, a controlled test is precisely what Olivia would need to do if you wanted to know what triggers your dog’s responses when you return home after a long period away. You have already taken an important step in solving this mystery because you have already proposed two hypotheses that could explain your dog’s reaction: 1) your mere presence 2) your family reaction to your presence. Now one would need to test which one explains your dog’s reaction better. One of the simplest ways of doing this would be to compare your dog’s reaction in two different situations: 1) You appear without any of your family members around 2) You appear in the presence of your family. You would then measure several behaviours including the appearance of tail-wagging,
approach/avoidance, growling/barking, and any other behaviours that you deem appropriate. Additionally, you could compare the responses in those two situations with the situation in which a stranger appears.
Although in scientific circles it is undisputed that animals possess memories, currently, there is an intense debate in the field of comparative cognition about which types of memories are present in animals. Some scientists argue that some animals, just like humans, possess so-called episodic or autobiographical memories – a type of memory that serves us to recall specific events of our personal history, e.g., the day that you got your first bicycle. If you think about it, you can probably recall, who was there, where the event took place and when it happened – all this information comes bundled together so that you are capable of re-experiencing the whole episode. Other scientists argue that the memories that have been reported in nonhuman animals lack some of these aspects and more importantly, they are not tied together – they are not autobiographical in nature. If you want to know more about dog memory, or more generally about animal memory, the current debates in the field, and the new research directions please check the following sources:
Dog memory
-Hare, B. & Woods, V. (2013). The Genius of Dogs. New York: Dutton.
-Kaminski, J., Fischer, J. & Call, J. (2008). Prospective object search in dogs: Mixed evidence for knowledge of What and Where. Animal Cognition, 11, 367-371.
-Fugazza, C., Miklósi, Á. (in press). Deferred imitation and declarative memory in domestic dogs. Animal Cognition. doi:10.1007/s10071-013-0656-5.
Animal memory
-General knowledge: Roberts, W.A. (1998). Principles of Animal Cognition. Boston: McGraw-Hill.
-Current debates: Clayton, N.S., Bussey, T.J., and Dickinson, A. (2003a). Can animals recall the past and plan for the future? Nature Reviews Neuroscience, 4, 685-691.
-New directions: Martin-Ordas G and Call J (2013) Episodic memory: a comparative approach. Frontiers in Behavioral Neuroscience, 7, 63. doi:10.3389/fnbeh.2013.00063. (Open access).
Interesting... I'll have to experiment a bit with this. My dog, a GSD, has already shown that she watches a number of things I do and reproduces them to accomplish her goals :-))) She opens fence latches, could open the garage using the opener (until I put a dog-proof cover over it), opens door that use lever latches, and can deal with crash-bar type water fountains. I particularly remember the fountain since she spent as much time getting her drink as looking at where my hand was placed :-)
As you acknowledge, this is not really a new concept... but it IS a poorly documented and exploited concept.