
The entire book, it seems to me, is founded on a logical error. The author believes the ideal diet for your dog is what approximates the "ancestral" diet, on the grounds that that diet is what your dog evolved to eat.
At first it seems to make sense. Wild fish live in water, so you keep your pet fish in water. Wild snakes eat mice so you feed mice to your pet snake. Wild dogs (or maybe wolves? This "ancestral" phase is never precisely specified) eat so much of this and so much of that, getting so much Calcium, Vitamin A and Vitamin D, so that's what your dog should eat.
What this line of reasoning overlooks is that what "ancestral" dogs ate reflected something other than those dog's choices and the hand of evolution: it reflected what was available.
Think of people. For 90% of our career as a species, we slept outdoors. That's our "ancestral" sleeping arrangement. Does that mean we'd be healthier sleeping exposed to the elements? Not likely.
Availability is one issue. Another is life span. Wolves (I don't know about wild dogs) live about five years on average. Even if their diet is optimal, it may only be optimal for an animal that lives a short life. (Similarly people: hunter-gatherers eat a lot of meat, but they usually die long before heart disease and cancer — known to be correlated to eating a lot of red meat — become an issue.)
Now I don't want to overstate my case. Your dog should surely eat a diet somewhat like, in-the-ballpark of, what wolves eat. It's unlikely your dog would be better off eating a completely different diet composed of things wolves didn't eat just because they couldn't catch them — say, seal blubber.
All I'm saying is that from there to decreeing that the "ancestral" diet is ideal in all its details, is a logical leap too far.
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