Chihuahuas take their name from the Mexican state of Chihuahua, where small dogs of this type were described in the 1800s. The AKC registered its first one in 1904. Adoptable Chihuahuas typically weigh 3 to 9 pounds and have a rounded head, big upright ears and either a smooth or long coat in nearly any color.
Many are bold, alert and strongly attached to a favorite person, which can show up as barking, wariness of strangers or snapping when handled roughly. Gentle socialization helps, though every dog varies. Chihuahuas often live 12 to 16 years, so adopting one is a long commitment. They're among the most common small dogs waiting for homes, and adults of every age and personality turn up, which makes it easier to match a dog to your household.