Q: Among the dogs I’ve had over the years, my small dogs lived longer than my large dogs. Is this generally true? If so, why?
A: Yes, it’s true, though no one is completely sure why.
When you think about the many species of mammals, you realize that large mammals live longer than small mammals. For example, elephants live much longer than mice.
However, within a given species, the smaller animals generally live longer than the larger ones. This has been documented in a number of species, but nowhere is it more pronounced than with dogs, probably because their size range — from the massive mastiff to the tiny Chihuahua — is so extreme….