Dogs evolved from wolves thousands of years ago (30,000 to be exact), a fact that is easy to forget with the sheer number of brands marketing high protein, grain-free diets for dogs that mirror that of the wolf.
The modern dog is an omnivore. This means they require a balance of proteins, fruits, vegetables, grains, and healthy fats in their diet to maintain optimal health. So while dogs may have descended from wolves, metabolically and genetically speaking, their nutritional needs are quite different.
And many dogs live very healthy lives on nutritionally-complete, plant-based diets.
All of that said, the majority of dog owners still want to feed their dogs meat!