Dogs have a scavenger/omnivore digestive tract than humans, shorter and 
more acidic to aid their ability to eat rotting things that would make 
us sick.

For much of the time man and dog have co-existed, man wasn't feeding 
dog.  At least not exclusively.  Dogs weren't caged; they were still 
their own main food providers, even if we threw them a bone once in a 
while after we'd gnawed off the surface good stuff.  We may have shared 
in a time of plenty, but when food was scarce, most of dogs were on 
their own.

After we started feeding them exclusively, we fed them what we ate, and 
back then, it was real food, so not much adaptation necessary. Processed 
commercial dog food is less than a century old, which even in dog years, 
isn't very long for that kind of adaptation to get far given the 
differences in their digestive tracts.  But now that they are eating 
processed foods, they are starting to show diseases of civilization, 
too.  Also, I think diseases that take a number of years to develop 
might not show up as quickly in a species with such a short lifespan 
compared to humans.  The diet doesn't have as long to mess with their 
genes before they procreate.

Just my theory...

Lisa in Alaska

On 3/26/2015 6:44 PM, Day, Wally wrote:
>>>   and also that evolution works much more rapidly than paleo people give it credit for.
> The domesticated dog has been with us for a long, long time. <snip> I would expect to see fairly noticeable adaptations in their digestive and dietary requirements. Yet, their basic dietary needs remain basically the same as they were millennia ago. I may be way off base... maybe it's because they are 'more' carnivorous than we... or maybe they are just have a better basic 'design'. Nonetheless, it makes me wonder.