Dogs have lived with people for at least 30,000 years.[source?] They are often called "man's best friend" because they fit in with human life. Dogs can serve people in many ways. For example, there are guard dogs, hunting dogs, herding dogs, and guide dogs for blind people. There are also dogs that are trained to smell for diseases in the human body or to find bombs or illegal drugs. These dogs sometimes help police in airports or other areas. Sniffer dogs (usually beagles) are sometimes trained for this job. Dogs have even been sent by Russians into outer space, a few years before any human being. The first dog sent up was called Laika, but died while there.