Dogs have been companions to humans for thousands of years, and they're keenly tuned into our behaviors and emotions. But just how much do dogs understand about us? More than you might think! Here are some unexpected ways that your dog may be in tune with you.

1. They Know When You're Sad

Dogs can sense when their owners are feeling blue. They might cuddle up to you or act more submissive when you're upset. According to a study in the journal Animal Cognition, dogs even approach people who are crying more often than those who are humming or talking.

2. They Understand Your Words

While dogs may not understand every word you say, they can associate specific words with actions or objects. Research in the journal Science showed that dogs' brains process both the meaning of words and the intonation in which the words are said.

3. They Sense Your Fear

Dogs can pick up on your fear and might act differently as a result. They might become protective or anxious themselves. A study published in Behavioural Processes found that dogs' behaviors change in response to the smell of human fear.

4. They Understand Your Routine

Ever notice your dog seems to know when it's time for a walk or dinner? That's because they've picked up on your daily routine. Dogs are creatures of habit, and they thrive on consistency.

5. They Know When You're Being Unfair

Dogs understand fairness and can become upset if they feel they're being treated unfairly, such as if another dog is getting more treats. A study in the Proceedings of the Royal Society B found that dogs stop performing a task when they see another dog getting rewarded more for doing the same task.

6. They Sense When You're Leaving

Dogs often know when you're about to leave the house, and they might respond by getting anxious or upset. This is due to a combination of understanding your routines and picking up on cues like you putting on your shoes or picking up your keys.

7. They Know When You're Not Paying Attention

If you've ever noticed your dog getting into mischief when you're distracted, it's not a coincidence. Dogs can tell when you're not paying attention and may seize the opportunity to break the rules. A study in Animal Cognition showed that dogs are more likely to steal food when they think humans can't see them.

8. They Understand Your Body Language

Dogs are experts at reading human body language. They pay attention to your facial expressions, posture, and gestures to understand your mood and intentions. This understanding allows them to respond appropriately to our emotions and actions.