If you raise your thumb in front of your eyes, then alternate having one eye open and the other closed, you’ll notice that your thumb appears to move. This difference in angle is how our brains measure distance, and is the source of most of our depth perception.
Believe it or not, humans are evolved to be excellent hunters. Our front facing eyes are adept at gauging distance. But we can still be fooled! These 30 photo illusions will play tricks on your eyes, can you spot what’s really going on in each one?