Scientists are still on the track of why humans yawn, and to add further interest, there are now many studies on which animals yawn and why they do so. If you’ve ever owned a fish, a reptile, a cat or a dog, or even a rat, a bat, or a ferret, you may have noticed these animals yawn. In fact most animals yawn, but it’s probably not because they’re bored or sleepy.

Some interesting studies have been done on the reasons why mammals yawn. For instance it’s thought that some primates, and possibly cats and dogs may yawn as a sign of dominance. Observation of dog and primate behavior has shown that alpha males and alpha females tend to yawn more frequently than do their beta counterparts. Yawning may actually be considered aggressive in certain species, since it is a chance to display lots of pointy teeth. If you wonder whether your dog or cat respects you, you might think about counting how often they yawn when they’re in your presence. You may not be the alpha dog or cat you think if your animal yawns frequently.

Scientists have also suggested that certain animals yawn as a cool down method. This may be particularly true when reptiles yawn. With most reptiles relying on ambient temperature to maintain body temperature, yawning might be a means for promoting rapid cool down. This may also work for animals that don’t sweat. Pigs and dogs may yawn because they don’t sweat. Exposing the mouth and tonsils to the outside air may cool down the head, even if only by a few tenths of a degree.

Researchers have also discovered that when animals yawn, this may have a contagious effect on other animals of their species. Sharks have been described in this manner, especially when they travel in large groups. A single shark yawning can set off a yawn reaction in the whole community, which can be pretty impressive, or slightly frightening if you’re close to a bunch of sharks with open mouths. Chimpanzees have been observed exercising contagious yawns too, but it’s still unclear why they do it, just as we’re not sure why humans are prone to yawn at the sight of other humans yawning.

Many insects do not yawn, and the main reason for this lack of yawning is that their breathing mechanism is very different from our own. Instead of having a central oxygen collection device, the lungs, most insects absorb oxygen from every cell in their body, which then is dissolved into fluid to carry to all the body’s tissues. Therefore, if you want a pet that doesn’t yawn at you, consider a nice cricket.

Typically, you’ll find most animals yawn, and you can view some pretty impressive pictures of animals yawning on sites like Google™, and other sites. It’s something that most members of the animal kingdom have in common, even if we can’t figure out exactly why we do it.