Are Dogs Mammals?

Dog, Nature, Woodland, Outdoors, Sitting

Written by Rebecca Bales

Updated: September 30, 2022

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The quick answer is, yes, dogs are mammals. Dogs have all of the attributes that make them mammals, and they have a long history of living alongside humans. They are related to foxes, jackals, and gray wolves.

So, what makes a dog a mammal?

They Give Birth To Live Young

Like other placental mammals, dogs give birth to live young. They gestate between 58 and 68 days. The young are born helpless. For the first two weeks, puppies are fed, cleaned, kept warm, and cared for by their mother. They can pull themselves around in a slow crawl.

At two weeks, puppies will open their eyes and their eyesight will improve over the next several weeks. They will interact with their siblings and mother, and their deciduous teeth will begin to poke through their gums.

By three weeks, puppies begin to show interest in their mother’s food. If this is encouraged, by offering soft, easy-to-feed meals in a shallow bowl, most puppies will taper off of nursing and eat solid food entirely at around eight weeks.

Additionally, mammals are distinguished from other animals by many unique features. Some animals don’t stay with their young at all and leave them on their own. The characteristics that make a mammal a mammal includes hair or fur, warm-blooded, live birth, mammary glands and a complex brain.

Some dogs have thin, short hair while others have thick, long hair.


They Have Hair

Like other mammals, dogs have fur. Depending on the breed, the hair may be short and thin, long and thick, or somewhere in between. It can be straight, wavy, or curly. Many dogs developed coats for a specific purpose, such as hunting dogs whose coats protect them from underbrush and retrievers who have a waterproof outer coat.

Their Lower Jaw is Made From a Single Bone

The structure of the lower jaw is the same in all mammals. The single bone, attached to the skull, gives the jaw incredible power. This makes it easy for the dog to chew and bite. Because of the strength of the jaw, proper training is important to ensure safety for everyone involved, and keep puppies from chewing on household items they shouldn’t.

They Have One Set of Replacement Teeth

Mammals do not continually replace their teeth. Their deciduous, or baby teeth, start coming in when they are between two and three weeks old. These teeth begin to fall out at around 12 weeks, and by six months most dogs will have a full set of permanent teeth, which must last them a lifetime.

They Are Warm-Blooded

Like other mammals, dogs are warm-blooded. This means they can regulate their temperature on their own. Unlike a reptile that needs heat to provide energy for hunting and other movements, a dog’s body can heat and cool itself on its own.


There are several internal features that all mammals share. While you cannot see these things with the naked eye, they are all part of what makes a dog a mammal. One feature is a four-chambered heart. The four-chambered heart does a more efficient job of oxygenating blood to send it back into the body than that of three-chambered reptiles and amphibians and two-chambered fish.

This access to well-oxygenated blood allows mammals, including dogs, to do more rigorous physical activities than other species.

Another feature that all mammals have in common is their well-developed diaphragm. While birds and reptiles also have diaphragms, they aren’t as well-developed as the ones in mammals. This allows for more efficient breathing and better use of oxygen.

Finally, all mammals have three bones that make up the inner ear. These bones are responsible for transporting sound waves and transforming them into neural impulses which can be interpreted by the brain as sound.

Because dogs are warm-blooded, they can regulate their temperature on their own, even after running.

© Raykova

Dogs are in the family Canidae. There are 35 other species that make up this group, and they all have a few things in common. Whether you are talking about domesticated dogs or the wild members of the canine family, such as dingoes, foxes, coyotes, and wolves, they all rely heavily on scent for nearly every aspect of their life.

In the wild, these animals use their nose to not only find prey but recognize predators, find a mate and avoid trouble. While a domestic dog doesn’t need to do all of these things, they still have a highly developed sense of smell and use it to explore their world.

Most mammals are omnivores, which means they eat both plants and meat. Some, such as wolves, are carnivores, and eat only meat. Canines that rely entirely on hunting to meet their nutritional needs often live in social packs, which makes hunting game easier.

While domesticated dogs are widespread, several members of the canine family face population struggles. Human activity, such as hunting and removal of natural habitats, has caused the red wolf, African wild dog, and dhole, to be recognized as endangered.

The History of Domestic Dogs

Archeological research has yet to pin down the exact time when canines joined with humans and became domestic dogs. What is known is that they are the oldest species domesticated by humans and have probably lived alongside humans as companions for over 15,000 years.

Dogs were domesticated before horses, cattle, or any other animal, and have continuously provided companionship.

It isn’t certain where dogs were first domesticated, but it was thought to be in Western Europe and Central and Eastern Asia. The process of domestication isn’t clearly understood, but probably took place gradually as wolves became socialized to the sight of humans and attracted to the smell of meat cooking over fires.

Over time, they began to consider the populated area part of their territory and would growl to alert humans to others approaching the area. The beneficial relationship developed from there and continues to this day.

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About the Author

Rebecca is an experienced Professional Freelancer with nearly a decade of expertise in writing SEO Content, Digital Illustrations, and Graphic Design. When not engrossed in her creative endeavors, Rebecca dedicates her time to cycling and filming her nature adventures. When not focused on her passion for creating and crafting optimized materials, she harbors a deep fascination and love for cats, jumping spiders, and pet rats.

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