We like to think about animals as having relatively stress-free lives. After all, what do they have going on that would stress them out? It’s not like they have responsibilities or a schedule. Our pets don’t have to go to school, earn money, or pay bills. By that logic, they should be happy most of the time. They live the life that all humans dream of.

But animals have emotions just like the rest of us. If you own a dog or cat, you’ve probably become pretty good at reading their body language. You know just like people, they have days where they’re happy, sad, irritated, anxious, and stressed.

So, it’s not surprising to know a variety of emotions affect animals of almost any species. Yes, even birds, fish, reptiles, and amphibians have good and bad days although they might not be quite as complex as ours.

But if there is one emotion most animals manage to communicate, it’s anger. Sometimes, they vocalize to let us know they’re feeling irritated, like a cat’s hiss or a dog’s growl. And in some instances, we can tell they’re angry just by looking at their faces… like these 75 grumpy animals.