in ,

Why Don’t Dogs Live As Long As Humans?

If you have ever lost a dog, you probably know how hard it can be. Losing a dog is like losing a best friend. No one will ever love you as much as your dog does. While dogs may have shorter lives than humans, they easily make up for it in the love they give. But why does a dog’s life have to be shorter than humans?  

Dogs don’t live as long as humans because of the aging process their bodies go through. In the first two years of a dog’s life, they mature and grow to the same age as a 20-year-old human. Breeding and human selection have caused many different dog breeds to become prone to more health-related issues.

These issues have caused some breeds to have shorter life spans like that of german shepherds and bulldogs. Each dog breed has a different life span, and the size and breed of your dog will greatly affect the time they have on this earth. While inbreeding has caused greater health issues, better diets and access to more health care have increased a dog’s life span over the last few hundred years

Quick Navigation

The Aging Process in Dogs

While many people still believe that one dog year is equivalent to seven human years, scientifically, that is not accurate. The saying likely came from the equation that humans lived for an average of 70 years, while dogs lived an average of 10 years.

In actuality, every dog breed ages differently, and that is why many dog breeds have different life spans. When comparing the age and maturity of a dog to a human, the first year of a dog’s life equates to the aging and maturity of a 15-year-old human. While year two equates to about 24 in human years. 

After the first two years, a dog’s aging slows and equates to an average of 5 dog years to each human year moving forward. Scientists have come up with these numbers based on breeding and growth in dogs as well as the aging signs as they show up in a domesticated dog.

While many people will still use the average of 7 dog years to one human year, knowing how a dog ages and matures in the first two years of life helps you understand why each year after is much sorter than that of a human.  

The difference between large breeds and small breeds

There is a general rule “the bigger the breed, the shorter the lifespan,” but there is no clear answer why larger breed dogs live shorter lives than smaller breed dogs. We will understand later why this goes against scientific rules of species and genetics.

Some scientists believe the size and lifespan differences in a dog have to do with the work the organs have to do to help keep the body going. There is more work involved in growing and running the body of a larger breed dog. 

A great dane will often live 7 to 10 years while a chihuahua can live on average 14 to 16 years. In the animal kingdom, it is usually the opposite, and large animals like elephants will live longer than small animals like mice.

Scientists have noted that many larger breed dogs tend to have accelerated growth and aging rates that can bring on more age-related health issues sooner than in small breed dogs. Sadly there is no concrete and accepted scientific answer on why this happens. Scientists have just started to study the aging process of our dogs. 

How to Improve Your Dogs Life Expectancy

Every dog owner wants to improve their dog’s life expectancy. While most dog breeds do have a top age, it has been proven that, like many humans, the healthier your dog is, the longer they will likely live. Here are a few factors that affect a dog’s life expectancy.

  • Genetics
  • Size
  • Environment
  • Diet
  • Exercise
  • Weight
  • Dental health

Common Signs of Aging in Dogs

Knowing the signs of aging in your dog will help you understand how to support and care for your dog as they get older. There are many ways you can ease the suffering or support the functions of your dog as they become a senior watching for these signs can alert you of the need to seek help from your vet. 

  • Arthritis or trouble moving the joints
  • Grey hair on the snout and face
  • Diminished vision and hearing causing anxiety
  • Increased need to sleep

The effects Dog Breeding Had on a Dogs Lifespan

The lifespan of different species depends on the species survival and reproduction in the wild. Dogs have been breed from the wolf species for generations by humans to become timid and domesticated animals. Wolves have an average life expectancy of 15 to 20 years, which mirrors that of some dog breeds.

Through breeding, humans have chosen the looks of a breed over survival necessities. For example, breeding favors softer short snouts, which cause breathing issues and heat aversions in many dog breeds like the bulldog.

Smaller head sizes reduce room for the brain, causing neurological issues and smaller brains in all dogs. There is a long list of breed-specific issues that have been chosen by humans for looks. After hundreds of years, these chosen traits have contributed to health issues in many different dog breeds. 

The process of dog breeding is not to make the species stronger but to make them cuter or look a certain way of removing the survival necessities that were originally in the species to help them live longer lives. It is common for working dogs to have longer life spans because the breeds need to stay physically fit, but this has also been watered down because of a smaller available gene pool and the inbreeding being done because of the smaller available pure breed gene pool. 

The Science Behind Animal Evolution

Aristotle believed that larger animals live longer because of the moisture in their body. He believed it took them longer to dry. This hypothesis has not proven accurate, but it did lead to the idea that animals with higher metabolisms live shorter lives because their metabolism helps them age faster. This hypothesis has also not stood up to scientific fact. 

The only fact that is agreed upon by scientists is the fact that larger animals live longer lives than smaller animals. Scientists have noticed that animals who are better at staying away from predators or have fewer predators live longer lives and age at a slower rate. This leads scientists to believe that animals like whales, elephants, and even people can afford to take more time to grow as they have less natural predators. 

How this Effects A Dogs Life Span

A dog is considered an adult at the age of one and a senior by the age of seven. While domesticated dogs don’t necessarily have a large number of predators, humans have caused issues in dogs because of breeding that has helped complicate base survival genetics.

Scientists use evolutionary pressures to study the aging process in different animals. Evolutionary pressures are pressures that reduce reproductive success in a species. These pressures are what cause many animals to change and evolve their genetics to ensure the future survival of the species. 

Many dog breeds are less than a few 100 years old and do not have the same evolutionary pressures involved in their breeding. Because of this, domesticated dogs do not necessarily follow the same rules as other species.

Even the size of the dog is opposite to what is expected in science as large breed dogs live shorter lives than small breed dogs that do not stand up to other species in the wild. Scientists believe Insuline hormones in dogs play a larger role in their aging process. The insulin is what helps a dog grow, and large breed dogs use more insulin to grow to their larger sizing. 

While breeding has caused more health issues in dogs, humans have been able to extend the average life of the domesticated dog in the last few hundred years with better food options, more vet services, and a better understanding of the animal’s genetics.

Obesity and inbreeding are likely going to start counteracting these improvements. The most important way to help your dog live longer is to keep them healthy with the right diet, regular check-ups, and exercise.