Dog science is on the rise as more and more researchers devote their time and resources to understanding the inner workings of how our best friends have evolved to become so intertwined with humanity. From dog biology to dog psychology, we understand more than ever about pups and their behavior. Curious to find answers to what science says about your dog? Keep reading about some of the more fascinating things we've uncovered.
The amount of time a dog spends sleeping depends on many factors, including his age, size, breed, health and activity level. All dogs require significantly more sleep than humans, which has to do with the amount of REM sleep that dogs get. While humans spend about 25 percent of their sleep in REM cycles, which is the deepest and most restful stage of sleep, only about 10 percent of a doggy nap is spent in REM sleep. This means that they need to sleep longer to make up for the imbalance.
Although dogs bark for a variety of reasons, biologists formerly thought that their barking didn't change depending on the message. More recently, however, research into the biology of a dog has discovered that dogs have elasticity in their vocal chords, giving them the ability to slightly alter the sound of their barks to convey different meanings, says Scientific American.
Spectrographic images of dog barks have shown differences in timing, pitch and amplitude, all of which vary according to context. The same is true of growling. While it's not yet clear to researchers what these different barks and growls mean, experiments have shown that dogs react differently to other dogs' vocalizations depending on the context. For example, scientists recorded a dog growling over food and growling at a stranger. When they played back the "food growl" while offering another dog a treat, dogs were more hesitant to accept it than when they heard the "stranger growl." Other experiments showed that dogs and people are more likely to react to a dog's "stranger bark" than to other kinds of barking. More dog science research is needed to decode every woof and growl, but it's becoming clear that there is a more complex communication element to a dog's barking — they're not just doing it for fun.
How fast a dog can run depends on the individual dog. Running speed is largely dependent on size, body shape, and leg length, as well as the age, health and physical condition. The greyhound averages about 45 miles per hour as the world's fastest dog, with the fastest ever member of this breed clocked at 50.5 miles per hour, says Wag!. While streamlined greyhounds and other fast breeds, such as whippets and Afghan hounds, appear to have been designed for speed, all dogs have the ability to make their bodies more aerodynamic when they run, either by flattening their ears to decrease wind resistance or pushing them back to avoid getting tripped up.
The way dogs move their legs also changes when they run. A walking dog moves their right legs and left legs together, while a running dog leaps with their front legs and back legs paired, allowing for more speed.
For some dogs, the ability to hop up on a couch is no amazing feat; for others stairs may be required to snuggle with you in your favorite chair; and still for other dogs containing them in fenced yards can be a challenge because of their jumping ability. Similar to a dog's running ability, a dog's jumping ability depends largely on their size, strength, age, health and body condition. It has been reported that the highest jumping dogs can clear 6 feet, but what might be more impressive are the small breeds that can jump multiple times their body height. Another component of dog's jumping is how far they can leap. Common in dock-diving competitions, dogs are trained to run and leap in the water to see how far they can make it — some achieving leaps near 30 feet The Labrador Site reports.
A dog's eyes are incredible and can see things that you and I can't see. However, a dog's vision isn't necessarily better than a human's. According to Veterinary Vision, a dog's eyes are positioned on the side of his head which results in greater peripheral vision, however their visual acuity (or their ability to focus on objects) is only about 20 to 40 percent of that of a human. This means that what a dog can distinguish as an object at 20 feet, a human with 20/20 vision could distinguish it at 90 feet. For this reason, dog's rely on their other senses a great deal to help them navigate the world.