I used to think I was a dog person, which lasted right up until I adopted a cat. While I’m still a huge dog fan, I no longer believe you have to prefer one over the other. There’s a reason cats are the most popular pet kids in North America!

Yes, cats are nothing like dogs: they are enigmatic, independent, sometimes aloof and always entertaining. Their completely unique natures are, in my opinion, their most endearing feature. It should come as no surprise that in addition to their one-of-a-kind personalities, they also have some pretty exceptional physical features and roles to play in our society. As a veterinarian, writer and cat enthusiast, it pleases me to no end to learn more about these fabulous furballs. Here are just five of my favorite unique cat facts!

1. Cats can use their mouth to smell

Have you ever seen your cat take a big sniff, then pull their mouth back in what looks like a sneer? That’s called the flehmen response, and it’s one of the wonderful, weird things that makes cats so unique. Cats have a special organ called the vomeronasal organ wedged up between the hard palate and the nasal septum. The vomeronasal organ is used to analyze pheromones, which is an important means of communication in the feline world. If you’ve ever gotten a good whiff of cat urine, you may make the same face … but unlike us, cats are actually gaining extra information from that stimulus.

2. Cats are well adapted to high-heat environments

Have you ever seen a cat pant? Hopefully not, because they aren’t supposed to. We all know that dogs use panting to dissipate heat, while humans sweat. Aside from a negligible number of sweat glands in the paws, cats do neither! Evolved from desert-dwelling creatures, cats have extremely efficient kidneys that can concentrate urine to a very high degree, meaning they can survive longer than other mammals with less water without becoming dehydrated. I watch my dark-coated cat Penelope seek out blocks of sunlight all the time … like many cats, she thinks “The hotter, the better!” Meanwhile my dog is laying on the coldest spot of floor he can find.

3. You can’t top a cat’s night vision

Cats are unusual in that they have both predator and prey adaptations. One of their most unique features is their slit pupil, which allows the pupil to contract more quickly than the circular pupils of dogs and humans. This means they adjust more quickly to changes in ambient light. They also have the largest eyes of any mammal relative to their size! They have several other adaptations meant to ensure they can see well at night, including more rods in the back of their retina as well as a tapetum lucidum, a reflective layer of tissue that gives their eyes that eerie green glow.

4. Cats could have changed the course of history

In the Middle Ages, the Black Death swept through Europe, killing off an estimated 25% of the continent. The causative agent of bubonic plague, Yersinia pestis, was found to be carried by fleas who moved about the countryside on rodents. During the Spanish Inquisition, cats were condemned as evil and killed by the thousands. This cat depopulation allowed the rodent population to explode, extending the effects of the plague. Who knows how many lives could have been saved if only cats had been spared and out hunting the plague carriers.

5. Hissing is a unique feline vocalization

Have you ever heard a happy cat hiss? Probably not. Though not all cats hiss, those that do are invariably upset or frightened. Experts believe hissing may actually have evolved as a mimicry of a snake hiss, a way to warn someone that whatever they are doing, the cat is not at all happy about it. If you have a cat who hisses, consider yourself lucky! It’s a clear warning to stop whatever is upsetting them before they escalate to the next level, something usually involving claws or teeth.

And that's just a few of the many amazing cat attributes. Do you have a favorite that didn't make this list? Share your thoughts in the comments section below!

Dr. Jessica Vogelsang, DVM