If we were to rank sea-dwelling creatures for their happy-go-lucky disposition, sharks would definitely sit right at the bottom of the list.
Known for their bad temper and inability to take a joke, they wouldn't be cropping up on our dream underwater dinner party guest-list.
But maybe we were wrong.
This astonishing image shows the very brave Eli Martinez making friends with a man-eating lemon shark. Apparently the surprisingly laid-back fish swam straight towards the Texan diver before turning at the last second to offer her fin for a palm-slap.
Dolphins, you might have some competition.