Chihuahuas take their name from the Mexican state where small dogs of this type were found in the 1800s, and genetic studies show they still carry a trace of ancient pre-Columbian dog ancestry. The AKC registered its first Chihuahua in 1904, and the breed is now one of the world's most recognizable toy dogs, with a rounded apple-shaped head, large upright ears and either a smooth or long coat in almost any color.
Many Chihuahuas are bold, alert and fiercely attached to their favorite people, with a big-dog attitude in a body that often weighs under six pounds. That confidence can show up as barking, wariness of strangers or snapping when handled roughly, so gentle socialization matters. Chihuahuas are among the most common small dogs in shelters, and adults of every age and personality are often waiting for homes.