According to the Amazon book description, "It was not, the authors argue, a biological leap that set humanity apart from other species, but a psychological one: namely, the uniquely human ability to deny reality in the face of inarguable evidence - including the willful ignorance of our own inevitable deaths."
In the interview, we were introduced to the term, "anthropogeny," which is the study of human origins vs. "anthropology," which is defined as the science of humanity.
Following is Austin's refutation (bearing in mind he has not read the full published work) of Varki & Brower's theory.
Humans evolved from dietary changes which affected our biology and allowed our biology to evolve easier and survive. Varki & Brower's theory is, by design, non-refutable because it is self-fulfilling. If we deny their theory to be true, we have denied it and therefore we have substantiated it.
Changes to the human diet have contributed the most to human evolution. Humans are designed for running long distances over long periods of time. The animals humans were hunting couldn't cool down while running, so humans were able to outrun their prey by causing them to overheat. The animals would collapse from exhaustion and the humans would easily be able to eat.
Roughly guessing, human psychology (the first "why?" question) occurred around 10-20,000 years ago. My interpretation of Varki's theory is that human evolution is just a bunch of freak accidents. Psychology requires hardware (i.e. the human brain). Therefore, biology trumps psychology. In order to be able to move my hand, I need my hand. My brain can't move my hand without the hand, itself.
Take an example of a glass that has a capacity to hold water. What if you just kept on filling that glass with water? There would come a point when the glass couldn't hold any more water. We require hardware to be able to program it with software. Without human brains evolving to a bigger size and more complexity, we wouldn't have the psychological capabilities that we have now.
Human evolution is about the physical human brain, not human thought. If we suddenly started thinking, "Oh, we're going to die," then that's not a good survival strategy, because we would be too busy thinking about that to do anything else. This is where Varki's denial theory comes in. He says it's a freak accident, but I argue that there can be no freak accidents without the material required. We need a banana peel to be able to slip on one.
Varki has a very lessened view of Darwinism. If we suddenly evolved big brains, we would need the food to fuel them. However, if we were still vegetarians and we hadn't had a dietary change, we wouldn't have evolved. Today, it's fine for humans to eat a vegetarian or vegan diet because we can acquire the nutrients necessary, with minimal effort.
Other animals that may have evolved a big brain haven't had the diet to compensate the power demand. Dolphins eat a lot of protein, but they are always hungry and they are always moving, burning off calories. Dolphins are among the more complex-brained mammals. Tigers eat a lot of meat when they can, but they have to hunt and catch their food. The protein that tigers consume is quite high, though they can't express their ingenuity in the same ways that humans can. Tigers have claws and paws, dolphins have flippers and teeth. None of these appendages can be used to make tools and shovels, for instance.
Humans are able to more easily express our ingenuity, with tools and protection (ie. shelter and armour) and dexterity. Wolves, hunting in packs, can see beyond the present. Wolves and dogs have intelligence without dexterity. The existence of a brain doesn't equal good memory processing, cause-and-effect understanding, etc. Elephants have some dexterity and good memory.
Evolution requires both a freak accident (genetic mutation) and the material to be evolved.
Humans tend to view intelligence as the expression of it (ie. a tool), however dogs, for example, demonstrate their intelligence through their behaviour.
It's possible that chimpanzees could evolve to be more human-like, with bigger brains, if their diet changes to include more protein. The human brain consumes approximately 20-25% of our daily caloric intake. Most vertebrate species' brains consume 2-8% of food energy.
While I agree with Varki, that humans today are living in denial, I propose that human denial is a learned trait rather than an evolutionary phenomenon. Denial is not the evolutionary factor that set us apart from all other species.
