Can Dogs Tell the Difference Between Night and Day?

Night and day - there's a reason people say "night and day difference."  To humans, there are no similarities between the opposites, night and day, but what if this isn't apparent to someone? 

Can your dog tell if it's night or day? It's difficult to say. This seems like such a no-brainer to humans, it makes you wonder if we've been ignoring this question all along when our dogs really have no clue... or do they?

There aren't really any signs that one can point to if their pup senses it is night or day. Humans tend to equate sleeping with night time. So, you might think this could be a good indicator, but really, it's not. Not all humans sleep at night, and if you watch closely, your dog sleeps whenever they please, for the most part. So, that can't tell us much, unfortunately.

Surprisingly, there has been some debate about whether dogs can tell time, in a sense, though. This is based on them knowing when you'll come home, even before you open the door to your house. So, a few signs you might notice if your dog can "tell time" or at least know when you'll be home includes barking and wagging their tail. They might also jump up on you and lick you when you arrive. They may stay in a particular spot, like by the door or window, when you come home. In addition, they might pace if you’re later than usual - it really depends on the dog.

If you come home at a different time than your usual routine, it doesn't mean your dog won't be excited to see you, but they might not act exactly the same way as usual. This is because dogs are very observant of routines. So, if you break yours, it might surprise them. 

If they weren't expecting you home, the first thing you might notice is it might take them longer to greet you. They may not be as jumpy or excited as they usually seem to be. Your pup might also even still be sleeping or outside in the backyard sunning themself. 

Don't worry, though, they're probably still excited to see you. You just caught them off guard. This is one of the main reasons some suspect dogs can “tell time”, in a sense. Some dogs act differently when humans are on time versus late.

Historically, night and day have been around for as long as the world has. No matter your beliefs, as long as our planet has existed, it has turned around the sun, making both day and night. So, that's generally what humans have understood for... well, forever.

Measurement of time, however, has not been around quite that long, but still a very long time, nonetheless. As far back as 3500 BC, people were using the sun to tell time with sundials. Sundials were a big thing and helped people know what time of day it was based on shadows. 

The first mechanical clock came about around 1510. The standard way of telling time came about around the 18th or 19th centuries. Now, humans have all kind of tools at their disposal to measure time including wrist watches, stopwatches, phones, and more. Really, the way humans tell time is merely a measurement, though. 

In the wild, animals are governed by night and day in terms of what that translates to for hunting. Generally, most wild canines prefer late evening through to early morning to do their hunting. This means that historically, the night meant go-time for wild dogs. 

Living with humans has changed the vast majority of the dog's habits - including when they sleep! Dogs no longer have to hunt, so instead, they base their schedules around when we feed them. This means they get up when we get up, as that's usually the first opportunity for them to be fed by us. Once we go to bed, there is no more chance of getting food, so generally, the dog will go to bed as well. It doesn't take long for this sequence of events to become routine, and many-a-owner has reported that their dog now tells them when it's bed time!

Scientifically, you would think dogs have the ability to tell the difference between night and day. After all, most dogs can see. So, why would they be able to see you throwing a ball or their dinner being served, but not be able to see if it's bright or dark outside? Research into how dogs see has revealed that they see much better than we do in the dark. This means that darkness doesn't impede their ability to go about daily functions like it does for us. 

However, dogs being able to "tell time" has been attributed more to their sense of smell. A lot of theories point to your pooch being able to tell how long you will be gone based on your routines, as well as how weak or strong your scent is in your home. If it's stronger, that means you recently left. If the scent is becoming weaker, you might be coming home soon. 

So, perhaps we can speculate that a dog just doesn't use their ability to see as much as their ability to smell. Maybe it being light or dark outside really doesn't make much of a difference to them, even if they notice it. Of course, they do notice your routine of getting up and going to bed. So, that could tip them off to what time of day it is. This is all speculation, though.

Are you interested in training your dog to tell the difference between night and day? Good luck! The best way to teach your dog is probably to let them study you and your daily routine. 

If you want to play when it's light outside, they'll learn that's when you play. If you give them their meals at certain times every day, they'll pick up on that too. If you go to sleep when it's still dark outside, they'll probably understand that there's nothing interesting going on after dark, and they might follow your lead. 

Your very best tool, in this case, is just letting your dog observe you and your habits. They'll adapt and follow, usually.