He has done research the the ancient ancestors of dogs as well as dog nutrition. The author has also researched paleo-biology, paleontology, megafauna, and is extremely interested in theoretical physics, astro physics, anthropology, archaeology, envirornmental sciences, geography, and biology.

So, why did he place wheat, corn, and beef as poor ingredients? 

Wheat is a wholesome grain and we humans consume it in great quanity but since it can be a source of allergies for dogs, why take the chance? There are a number of grains that can replace wheat and provide carbohydrates and protein in sufficient quanity. These are millet, flaxseed, brown rice, oats, and barley... these are found in the better quality dog foods. My dog eats the grains mentioned rather than wheat.

Corn is a grain and like wheat but can be an allergen as well. Corn is inexpensive and used as cattle feed. When used as a component for dog food it can increase a dog's sensitivity to corn. Good dog foods use other grains and vegetables to obtain carbohydates, protein, and nutrients. My dog does not eat kibble with corn.

Beef is a protein source with 3 natural occuring growth hormones: Oestradiol, Progesterone and Testosterone. Also 66% of U.S. beef contains 3 synthetic growth hormones: Zeranol, Trenbolone, and Melengestrol. (see beef). Knowing this, my dog has never eaten beef.

My philosophy is if the above wheat and corn can possibly cause allergies, then why even feed your dog these ingredients? Beef is a no-brainer. You may agree or disagree with the above. It's your call. The info is for you to read.