A cat’s hairball is technically called a “bezoar.” Cats spend two thirds a day sleeping. A 9 year-old cat has been awake for only 3 years of its life. Cats have approximately 40 recognized breeds. A group of felines are called a clowder. Cats and humans have identical regions in their brains that are responsible for emotions. A cat keeps its head level when it chases a prey. Humans and ogs bob their heads up and down. Cats do not have a sweet tooth. Scientists believe this is due to a mutation in a key taste receptor. Currently in the world, there are more than 500 million domestic cats. Like the fingerprint of a human, a cat’s nose pad is ridged with a unique pattern. Cats can make about 100 different sounds. Dogs, in contrast, only make about 10.