When people think of house cats, some words come out:"cute," "slow," "lovely" and so on. Do you know that humans (人类) have kept cats as pets for over 9,000 years?

Without any facts, we can only guess at how humans and cats were together at first. Most people believe that cats were one of the last animals to be tamed (被驯化) and kept as pets in early Middle East. They were tamed after other animals like cows, dogs, pigs, and sheep because cats couldn't make delicious milk or help humans carry any things.

There are some things that cats can do well in, like getting mice, one of their favorite foods, and some other vermin that destroys (毁坏) the plants and is bad for humans. Some scientists said that this might be how cats and humans became friends. When early humans began farming for food, their food stores were a great place for hungry mice. Wild(野外的) cats weren't going to let them run away, so they followed the mice into human villages. As time went on, cats could live with humans well. Finally, the wild cat of 9,000 years ago became the house cat of today.

Unlike dogs, cats could leave their human owners and go back to the wild at any time. They don't lose their natural abilities(能力): their perfect seeing at night and hearing, their sense of smell and so on. House cats can also get their own food. Some people may even wake up to see little "gifts" from their cat, like dead birds or mice.

This kind of thing doesn't make us angry too much, because there are now more than 600 million cats living in homes around the world.