He talks about the squat vs the deadlift in terms of primal / evolutionary movements and refers to those who think squats are not "evolutionary," but think deadlifts are.
He points to Evolution and Training: An Interview with Dr. William Meller
S: I know when we talked before you said that a heavy deadlift isn’t the most natural thing – picking up something heavy from the ground – but you said that squatting was very natural for us.
M: Well, look at the size of the various muscles in our bodies, and what’s the biggest muscle? Your quads, your anterior thigh, right? There is a reason for that. It has to do with standing up and jumping, lifting and climbing up rather than bending over from the waist. Before we were upright, two-legged walking primates, we were four-limbed primates and we did a lot of climbing. We probably didn’t stand up at first to walk on the ground; we really stood up so we could reach a higher branch and keep climbing and pull ourselves up to the next branch using our biceps and upper-body strength. In climbing trees, there’s a lot of squatting and pushing up just using your legs, using your arms for balance and gripping and pulling. By doing that, we developed a more upright posture, so that when we did get down on the ground, we were able to walk and then even run, which turned out to be a huge advantage.
Read the rest - it is interesting.
About 2 years ago I mentioned the "Third Wolrd Squat"
You'll notice that in third-world countries, there will be a lot of situations where people are hanging out or working, and rather than sitting or kneeling down, they squat. They can sit like this comfortably for hours. It seems like a simple thing and can be easily overlooked, but try it some time. The average North American adult can't even get into this position, let alone stay there for any length of time.
I've also pointed to material on deadlift form and Gray Cook's instruction to maintain the squat but train the deadlift.
Anyway, an interesting debate.