By Dr. Robert Thorson

I recommend the pulp fiction Tarzan books by Edgar Rice Burroughs for reading across the curriculum in middle and high schools. These juicy adventure novels would agitate bored students to learn more about human evolution, colonial racism, gender relations, plot technique, and body movement than their dumbed-down, politically correct, spiritually bland and dated textbooks.

Sadly, textbooks designed for public schools are the result of a mass-market economy where publishing corporations defer to cautious administrators, who defer to school boards, who defer to the voters. Anything remotely provocative will send the buyer elsewhere. Texts are to publishers as fast food is to franchises. With a guaranteed market, the goal is the delivery of palatable nutrition or information to the broadest possible audience, not a memorable meal or learning experience, respectively.

To see how vetted and dated texts are, I ask you to monitor how long (if ever) it will take for the publishers to respond to a great idea that Tarzan, a.k.a. Lord Greystoke, would have loved. In this month’s Science, three British authors combined field observations about orangutans with vertebrate anatomy, paleontology and paleoecology to re-interpret the conventional wisdom about human walking.

When Tarzan wanted to move through the jungle quickly and safely, he did so above the ground, swinging on vines, running on branches and leaping from tree to tree. According to the new study, titled “Origin of Human Bipedalism As an Adaptation for Locomotion on Flexible Branches,” this is where the original adaptation for human walking occurred. This idea is so cool that it should be dangled as a morsel in front of every public high-school school student, especially young alpha males.

But I doubt if you will see it in their texts for years, if ever. To expose impressionable young minds to the dangerous fact that humans learned to walk with the monkeys would be unthinkable to a parent believing that humans were either created in God’s image or are the perfected end products of evolution.

Every text covering the animal “kingdom” should be honest enough to mention that humans are animals. They should be accurate enough to question the conventional wisdom that our antecedents came down from the trees and learned to knuckle-walk as chimps before standing fully upright. They should be interesting enough to link bipedal walking on terra firma to forest fragmentation and expansion of the savannah as the climate became drier. How many texts meet these standards today?

According to the new study, upright walking did not evolve to free up the hands for making tools, to carry an infant, to hold weapons or to forage for food. Nor did it evolve to help humans reduce their exposure to the overhead sun or to enhance “full frontal” displays of dominance. Instead, upright walking evolved as an adaptation for horizontal movement on springy branches within the tree canopy, either to travel from tree to tree, to reach food, or escape predation.

The most effective way for a large animal to move on wiggling branches is to fully extend the lower limbs between the foot and the hips while using long arms for balance. This original upright condition was retained by the orangutan lineage. It was lost by ground-dwelling chimpanzees and gorillas, whose locomotion in trees is more vertical than horizontal. It was retained by our antecedents who modified it for life on land. This explains why the earliest well-known member of our lineage (Australopithecus afarensis) was a fairly good walker and why we (Homo sapiens) have unnecessarily long arms. Being able to pitch a fastball or throw a spear is a throwback to a time when we first learned to walk.

The Tarzan books by Edgar Rice Burroughs were the first to transport me away from conventional middle-class life. I read them in elementary school, picking up tidbits of zoology, ecology, anthropology and technology along the way. I read them in college, discovering the author’s white male chauvinism, which today could be used to ignite multicultural student discussion. I read one in Spanish a few years ago to help learn the language.

Learning can be fun, textbooks notwithstanding.