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The "two-minute warning"
“Okay, Harry, I’ve got a meeting soon, so go pee and poop.”
People often ask me if dogs have a sense of time and what that perception might be like to them. There's no shortage of opinions on dogs and time. On my frequent forays to dog parks or when I see people walking their dogs I often hear statements like the ones above. I silently chuckle whenever I hear someone give their dog a "two-minute warning," as if the dog has his or her own stopwatch, mobile phone, or an internal clock. I also hear people say something like, “You have five more minutes, so hurry up and pee or play with your friends. Then we have to go.”
I've also observed that if people have to call their dog more than once, they often get testy and say something like, “What took you so long? I’ve been calling you for ten minutes. We need to leave now” or "Where have you been? You sure took your time coming back to me so you only have a few minutes to see your friends." I often wonder if dogs think something like, “Huh, how long is ten minutes?" or "How long is now?”
Dogs often sniff their friends as vigorously as they do less familiar individuals and strangers, even if they’ve been apart for only a few seconds. I remember smiling as Jethro, a dog with whom I shared my home, would vigorously sniff Zeke after Zeke was gone for less than a minute. Zeke would patiently allow Jethro to run his nose all over him, and, on occasion, Zeke seemed to be saying, “Hey, I just went down the road to pee and to see our friend Lolo.” Dogs don’t seem to question the need to sniff, and I’m sure they know what they’re doing. Perhaps it’s like when people text message only seconds after leaving a party. What else is there to say? Sometimes, you just want to check in again.
So, what do we know about how long 10 minutes, 10 hours, or 10 weeks is for a dog? Actually, little to nothing. There is, however, one study on how dogs sense time to which many people make reference. It's called "The effect of time left alone at home on dog welfare" by Therese Rehn and Linda Keeling (only the abstract for this study is available for free online, but registered users can download a PDF here). These researchers studied the effect of time left alone on the behavior and cardiac activity of 12 dogs. Dogs were left alone for 30 minutes, 120 minutes (two hours), and 240 minutes (four hours) and were videotaped before and after their humans left and came home.
Detailed data are included in the online abstract and the authors conclude, "According to the results of this study, the effect of time left alone was shown by a more intense greeting behaviour by the dog towards their owner as well as by a higher frequency of physical activity and attentive behaviour when the owner returned, already after 2 h of separation." They go on to write, "Although this study cannot distinguish between whether dogs were aware of the length of time they were alone (but did not signal it) or whether they were unaware until reminded of it by the return of their owner, it does confirm that dogs are affected by the duration of time at home alone."
Can Dogs Smell Time?
Some people have even wondered if dogs can smell time. In her book called Being a Dog, researcher Alexandra Horowitz suggests that dogs can smell odors that are in the process of evaporating, and, in this way, they can track time (and perhaps that’s why they have a good sense of when their human is coming home). I don’t know if this is so, but perhaps they can do this in certain instances.
Given my own and others’ observations, it seems as if dogs can tell not only who peed somewhere, but also how long ago with some degree of accuracy. Still, this hasn’t been proven, and so we really need more research to tackle this daunting but interesting possibility. Even if dogs actually can “smell time,” tracking the faintness of odors to learn how long ago something happened, they certainly don’t tell time in human terms.
So, do dogs have a sense of time? It seems reasonable that they have some sense of time, dog-wise, but we really don't know what their understanding of the passage of time means to them. Yet, this doesn't stop people from acting as if dogs know what's happening when they tell then they have a limited amount of time to play, pee, or otherwise, occupy their time. Of course, asking what a dog's sense of time might be does not mean they simply live in the present. Clearly, they're influenced by past experiences and can anticipate future events such as meals and walks. (For more discussion on this topic please see "Dogs Don't Remember Yesterday, Claims Psychologist," a statement with which many others and I strongly disagree.)
Studying how dogs sense time is a wonderful area for formal research. There are practical and theoretical aspects to this avenue of research and I look forward to seeing what we learn about what's happening in a dog's head when they hear something like, "Go play for five minutes and then we'll shop for a few minutes and then go home."
Please stay tuned for more research the cognitive lives of dogs. This is a "hot" area of study and I feel certain that we'll see more studies on what the "two-minute warning" means to our canine friends and learn more about what it's like to be a dog.
