While how long a dog will live depends on how well it is cared for, the dog’s breed can also determine its lifespan. Maltese dogs have an average lifespan of 15 years. Females of this breed tend to live a year longer than males. Beagles usually live to around 15 years old. The oldest known beagle was named Butch and lived to the age of 27. Shi Tzus will usually live just as long as beagles and are famous for making great lifelong companions. Cockapoos, which are a cross between a cocker spaniel and a poodle, tend to live for 16 years on average. Jack Russel terriers also live to be around 16 years old and are famous for their high level of energy. Despite being one of the smallest breeds, chihuahuas are one of the longest-living, with an average lifespan of 17 years. The schipperke only grows to be about 13 inches in height but lives for around 17 years. The New Guinea singing dog is one of the world’s rarest dogs, with only around 100 currently living in captivity. This dog is known for its singing howl and has an average lifespan of 18 years