Communication is also possible among bees through their sense of smell. A group of bees, called a colony, uses smell to protect itself from other bees. This is possible because all the bees in a colony have a common smell. This smell acts like a chemical signal. It warns the group of bees when a bee from a different colony is near. This way, bees from outside cannot enter and disturb a hive (the bee colony's home). If an outsider does try to enter, the bees of that colony will smell it and attack it.