Your tongue is germ free only if it is pink. If it is white there is a thin film of bacteria on it.
Laughing lowers levels of stress hormones and strengthens the immune system. Six-year-olds laugh an average of 300 times a day. Adults only laugh 15 to 100 times a day.
Roosters cannot crow if they cannot extend their necks.
Your left lung is smaller than your right lung to make room for your heart.
When hippos are upset, their sweat turns red
