No one is quite sure when humans first domesticated dogs, however, dogs and people have been working side by side for thousands of years. Dogs have become an integral part of many people’s lives, not just as companions, but also as guide dogs, search-and-rescue dogs, and bomb- or drug-sniffing dogs, such as the ones used last month for Super Bowl security. The Transportation Security Administration used about two dozen dogs to monitor passengers coming in and out of the Newark, NJ, airport.
Today, police forces in major cities use police dogs to track criminals, sniff out illegal materials, search buildings, and do other jobs human police officers can’t do as well as a dog can.