Where did dogs come from? Dogs came from wolves, a very long time ago. Dogs are in a family of animals called canids. Wolves, coyotes, foxes and jackals are canids too. Dogs have lived with people for at least 14,000 years.

In a grave in Germany, people were buried together with a dog. The grave is from about 14,000 years ago. Dogs have been helping people since ancient times. People have used dogs for hunting, guarding and herding. Guide dogs help people who are blind get around.

A dog's sense of smell is far, far stronger than a person's. A dog's nose has more than 100 million smell receptors. A person's nose has about 6 million. The part of a dog's brain that works on smells is about 40 times bigger than the same part of a person's brain.

Dogs use their noses and their eyes to learn about the world. Dogs can see colors, but they see mostly blues and yellows. They can hear very high sounds that people cannot hear. A puppy is born with its eyes closed. It cannot see at first.

Search and rescue dogs use their noses to find missing people. They also find people after disasters. In 1925 sled dog teams carried medicine across Alaska to the town of Nome. More than 20 mushers and their dog teams passed the medicine along.

Here is how to meet a dog. Ask its owner if it is okay to pet it. If a grown-up says you can, let the dog sniff your closed hand first. If a dog you do not know comes up to you, stay still and quiet instead of running.

Words to know

• canids: dog family
• receptors: smell sensors
• mushers: sled drivers
• herding: moving sheep