How did a wolf become a pet? Dogs came from wolves, a very long time ago. They have lived with people for at least 14,000 years. Scientists do not agree on when or where dogs were first tamed. One idea is that calmer wolves hung around people's camps to eat leftover food.

People have used dogs for hunting, guarding and herding. Guide dogs help people who are blind get around. 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. Every March, sled dog teams race in the Iditarod, which remembers the 1925 serum run.

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, while a person's 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 hear sounds as high as about 45,000 hertz. People top out near 20,000 hertz.

As of November 2026, the American Kennel Club recognizes 205 dog breeds. In late 2025 the club added three new breeds. One of them is the Teddy Roosevelt Terrier. Flat faces, like pugs and bulldogs have, can make it hard for dogs to breathe. Dogs can also see colors, but they see mostly blues and yellows.

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. Leave a dog alone when it is eating, sleeping or chewing on a toy. If a dog you do not know comes up to you, stay still and quiet instead of running.

Dogs have been helping people since ancient times. In a Russian experiment, scientists bred the tamest foxes with each other. After many generations, the foxes acted like friendly dogs. A puppy buried with two people about 14,000 years ago had been sick for weeks. People took care of it.

Words to know

• tamed: made gentle
• hertz: a sound unit
• receptors: smell sensors
• breeds: kinds of dog

The short version

Dogs came from wolves, a very long time ago, and they have lived with people for at least 14,000 years. Scientists do not agree on when or where dogs were first tamed. One idea is that calmer wolves hung around people's camps to eat leftover food.

Quick facts

• Dogs came from wolves, a very long time ago.
• Dogs have lived with people for at least 14,000 years.
• Scientists do not agree on when or where dogs were first tamed.
• A dog's nose has more than 100 million smell receptors, while a person's has about 6 million.
• As of November 2026, the American Kennel Club recognizes 205 dog breeds.