Polar bear
A polar bear’s skin is black and its fur is see-through; it only looks white.
Frog
The wood frog freezes solid in winter, heart stopped, and thaws out in spring to carry on hopping.
Duck
A duck’s quack does echo; it was tested scientifically in 2003, because someone had to.
Camel
A camel’s hump is full of fat, not water, which surprises everyone except the camel.
Zebra
Zebra stripes seem to confuse biting flies, which cannot work out where to land.
Seahorse
In seahorses it is the male that gets pregnant and gives birth, often to hundreds of babies at once.
Rat
Rats laugh when they are tickled, and have been taught to play hide-and-seek with people.
Narwhal
A narwhal’s tusk is a tooth that grows through its lip in a spiral, and was once sold as unicorn horn.
Horse
Horses cannot be sick, and can doze standing up because their legs lock in place.
Dolphin
Dolphins sleep with one half of the brain at a time, and have whistles that work like names.