Why do dogs live shorter than humans?

Dog with owners

Unfortunately, for their owners, dogs tend to live a shorter life than humans do. On average they live for about 9 to 12 years, depending on the dog breed and size of the dog. Have you always wondered what the reason is for dogs living a shorter live than humans? Or have you questioned yourself on what influences the life expectancy of your dog? Then please read along. Below you will find the answers to your questions! 

 

Biological explanation: metabolic rates and acceleration 

In general, metabolic rates help explain why certain animals live for a longer period of time, versus others. According to these metabolic rates, a large animal will live longer than a small one. This has to do with the fact that larger animals tend to have a lower heart rate and therefore do not take away as much energy from the heart than smaller animals. By being more careful with the heart, larger animals can thus live longer, compared to smaller animals.

However, this is not the case for dogs. Smaller sized dogs tend to live longer than larger dogs. There is no clear explanation as to why this is happening, although some researchers believe that the process of metabolic rates might be reversed for dogs. They argue that larger dogs grow at an even faster pace than smaller dogs, which is why their organs tend to be more active. In turn, this can lead to those organs to cease faster too.  

This accelerated pace in which dogs grow also makes them less likely to live a longer life. As dogs need to develop their bodies and their organs quicker, it can take a lot of toll from their bodies to do so. This in turn makes it more likely that their organs will stop working within fewer years. Also, dogs grow up way faster than humans do. For example, most dogs tend to be considered grown up from their second birthday. Whereas humans are only considered as an adult from the age of 21. This type of acceleration can also make dogs more vulnerable to living a shorter life than humans do. 

Dog playing