What's better...ancestral or natural history?

The idea of ancestral diets is an interesting one for me.  I hear it when people say they want to feed raw diets..."I want to feed a more ancestral diet" and "dogs and cats are carnivores", and I see it all over the marketing of pet foods, particularly grain-free foods.  What does that mean to everyone?

In reality there are more than 260 mammal species listed under the order Carnivora.  Yes, that list includes the cat and the dog, and closest taxonomic ancestors to both, the European wildcat and the wolf.  However, it also includes otters, civets, seals, and bears.  That last category is one of my very favorites to discuss in terms of comparative nutrition because it includes the Giant panda.  Oh yes, indeed they are carnivores in every sense of the word.  Anatomically they have short digestive tracts and limited ability to ferment fiber...surprised? The difference is that panda's have evolved and adapted to their environment and have lower requirements for protein and energy compared to other carnivorous species.  If' you've ever seen panda poo, you've noticed that it looks just like panda food.  They must consume gigantic amounts of bamboo just to meet those low energy and protein requirements (also why they don't move a whole lot).  If I wanted to feed a panda like their other relatives (carnivores), I'd likely produce very fat pandas with metabolic issues.  While we could feed pandas the same diets we feed other bears, we certainly do not...they are fed primarily bamboo as most of you already guessed.  Why then do we constantly focus on wanting to feed dogs like wolves and cats like tigers?

When it comes to felids, I won't argue with anyone that chooses to feed a strictly raw meat or whole prey based diet.  Cats have not evolved to be anything other than obligate carnivores.  Their protein requirement is twice that of dogs and they require vitamins that are unique to the consumption of organ meats that other carnivores do not require in the same high concentrations (taurine, vitamins A, D, and niacin). 

Canids on the other hand are not obligate carnivores...except one species.  I love discussing canid species as their variation in diet and natural history is nothing short of amazing.  Consider the little bat eared fox that consumes almost exclusively insects, or the maned wolf whose diet during portions of the year is made up of nearly 70% plant material from a fruit in the same family as the tomato.  Then, consider the only obligate carnivore canid...the African hunting dog (pictured below thanks to Omaha Zoo keeper Emily Wiley). These incredibly beautiful canids have never been observed consuming anything other than meat.  Most people aren't surprised when I tell them that I can't feed these species the exact same diet at the zoo and indeed their captive diets are not at all similar.  Maned wolves in captivity thrive on a diet that most of you would consider tragically high in carbohydrates and grains.  I must consider each individual species' natural history when I formulate diets. 



So, why on Earth do we seem to forget to consider that in respect to the species that live in our homes? Now, don't take this wrong, I'm not by any means saying that you should feed your dogs a high carbohydrate diet.  I believe quite the contrary.  The dog evolved because of us and the food we consumed. They thrived and became what they are today because we fed them a huge variety of dietary ingredients just like we fed ourselves.  It wasn't until the last century or so that we started making highly processed specialized dog foods and then deciding that only one food was appropriate (that idea we can thank the petfood industry for).  I don't believe that one food is appropriate for pets and I feel we should provide them with variety that their natural history dictates.  I know I've said it before but my dogs would be hard pressed to recall their diet over the last week because of the variety.  I do feed rotated kibbles, canned foods, raw, fresh fruits and veggies, some grains (mostly oatmeal), eggs, and fish.  The beauty of this is the result that I can feed them just about anything and not have to worry about GI issues.  Sadly, our society has been so conditioned to only feed our pets one diet that we've prevented most of our pets from developing the ability to cope with the variety their natural history tells us they should have.   

So, is it really that we want to feed our pets an ancestral diet or is it more that we want to feed them a more natural diet based on their natural history? To me, that makes a whole lot more sense.