Gobies make up the largest family (Gobiidae) of fishes in the world, with over 2,000 species. In this large family you can also find the smallest fish. The gobies in this photo are about one inch long (2.5 cm), and most in the family are less than four inches. Because of their small size gobies must work to evade their many predators, often through burrowing or special mutualistic relationships with other animals. 

“It’s quite normal for this type of goby to sit still on hard coral like this. I spotted the first of these very small fish and set up my camera for the shot. Just as I was about to take a picture, a second goby came out of nowhere and sat on the first one. I quickly corrected the frame and took two or three shots before both of them disappeared. It was an incredible moment.”-- Nature's Best Photographer, Tobias Friedrich