Dogs
As a rule, the larger the dog, the shorter the lifespan. However, some breeds like bulldogs, boxers and Cavalier King Charles Spaniels have shorter life expectancies than their size would suggest due to genetic disadvantages.
Large-sized breeds (e.g. Great Danes and Irish Wolfhounds): 6-8 years
Medium-sized breeds (e.g. Labradors and Huskies): 10-12 years
Smaller-sized breeds (e.g. miniature Poodles and Chihuahuas): about 16 years
Other popular pets
Cats: 14-18 years (though indoor cats usually live longer)
Mice: 1-2 years
Rats and hamsters: 2-3 years
Rabbits: 8-10 years
Guinea pigs: 4-6 years
Hairless guinea pigs: 6-8 years
Miniature pigs: 12-15 years
Birds
In contrast to dogs, smaller bird species tend to have shorter life expectancies than their larger relatives.
Canaries: 8-16 years
Finches: 3-6 years
Budgies: 8 years
Lovebirds: 8-12 years
Conures: 10-20 years
Amazons: 20-30 years
Cockatoos: 25-40 years
Macaws: 25-40 years
Reptiles
Ball pythons: 15-20 years
Boas: 15-25 years
Bearded dragons: 5-10 years
Corn snakes: 10-15 years
Iguanas: 15-20 years
Tortoises: 100-150 years
Geckos: 10-20 years
Chameleons: 7-9 years