Not sure, but I did find this info: http://www.madsci.org/posts/archives/Jan2003/1043288560.Zo.r.html Memory can mean everything an animal (or person, or computer) has learned. We know animals can learn because their behavior changes with experience. But what memories do animals have? Humans are aware of remembering events. It is not clear how to test for such awareness in animals. However event memory is only part of human memory. What is called “semantic” memory, or memory for facts, does not seem to generate the same kind of awareness. Motor memory, or memory for movement, also does not create the same awareness. So while animals might not reminisce, or think about their memories, they do have semantic and motor memories. They store mental representations of objects, events, and so on. What kinds of things do animals learn? Motor skills (motor programs) like how to catch a Frisbee. Spatial memory, like when and where to find food. Social memory, like who is nice to them and who is not. Animals can remember events. Experiments have been done with rats, monkeys, dolphins pigeons and lots of other animals (Grice 1948, Smith 1951, Garcia & Koelling 1966, Thompson & Herman 1977, Sands & Wright 1980, Roitblat 1980) that show that animals learn to respond to certain sounds or pictures. Birds learn migratory routes and songs Animals also have memories of places, or spatial memory (Tolman 1932) That is why rats can remember how to run a maze. (Deutsch 1960) Birds have memory for places, and so do squirrels and dogs. Even bees have memory for places but we don’t understand it as well. Animals will remember some things for a very long time, and some may remember things after just experiencing it once or twice. But they also don't remember other things after experiencing them over and over. so animal memory can be very strong, in areas in which the animal can remember. Animals tend to remember things that are (or were at some time, to that animals ancestors) inportant to their survival. One of my favorite odd facts is that rats can't throw up. And since they can't throw up, if they eat something poisonous, they will die. So a rat faced with a new food (which it does not remember - it's a new food, right?) will just nibble a bit. If it gets sick soon after, it will avoid that taste for a very long time. You could make a maze for a rat and a maze for a dog, and see which one remembered how to run the maze after 5 tries. You could show the rat and the dog where food is hidden and see which one remembers it better. Or you could even train a rat and a dog to remember that a picture means food is underneath it, but that might take a long time. Have fun with your project!

i think they have because if a dog hasnt seen you for a while they will still recognise you and wag their tails etc.

dogs do not have long term memmory. that is why they can be put into kennels and re-homed. or can be sold as pups.

Well, Dogs dream don't they? In dreaming their mind is either recollecting some event, or is imagining some fantasy event. So I reckon they have a less "black and white" - slotted into pigeon-holes type memory than is suggested. From my experience over many years with many pet dogs I would suggest that a dog's memory is as complex as the memory of those other mammals - you know those er, human ones. They remember what interests them and discount what doesn't. They have a sense of self-preservation, just as we do, and so remember not to go back to where things fall onto them or to where unexplained explosive sounds startle them. You wouldn't have a pee where some mysterious explosion once happened... I know that dogs can be as cunning or as manipulative as children. If you have experienced a dog's antics when asking to be taken for a walk, then noticed it's dissapointment when you don't go on it's preffered route. I've compared a dog with a child because an adult dog is the same age as a human child and has only been able to spend that same amount of time in assimilating it's cache of knowledge. The more time you spend trying to educate your dog the more the dog will remember. The dog will also remember things from it's own doggy experiences of life. As I said at the start. It will only remember what is interesting. If the dog doesn't associate with a topic it will discount it. - Just like I do! Have you ever climbed a mountain or swam an ocean in your dreams? Well maybe a dreaming dog is doing the doggy equivalent...

Dogs do have long term memory. Thats why they can be reunited with their owners years later and still remember them. I heard of one dog that was lost for like 10 years and when the owner found him, he ran right to her. In my own case, I have one dog that was given to me by someone that lives close. It's been about 5 years now, but everytime we walk by his house she pulls towards the house like that is where she belongs. But having said that, dogs do live in the present, meaning you can always change their minds about something in a negative or in a positive way based on what is happening right then and there.

Yes, they can remember things for quite awhile. We had not gone to visit my parents for nearly 8-9 years and as soon as we turned the corner to go up the street, the one dog who only had visited the place a couple of times, got up and was so excited. And they remember people from their past.