Is Gigantopithecus Still Alive?
Mark A. Hall and Loren Coleman
Anomalist Books, 2010
In True Giants, Coleman and Hall tackle a question that's hung around the edges of primate cryptozoology without being fully addressed: Are sasquatch and its ilk (assuming they exist) the tallest primates on Earth, or could there be an additional species, presumably a modern descendant of Gigantopithecus blacki, that forms the basis for worldwide legends of giants 9-20 feet tall? I greatly respect Coleman, and Hall is a researcher of prodigious skill, but this slender volume didn't change my thinking on this.
The authors admit up front that we don't know what kind of skeletal structure works in such an animal. To me, practical knee joints are especially hard to visualize: human knees are problematic even for people of ordinary height and chronically troubled for very tall people. Giraffes manage their True Giant-like height with fairly normal mammalian knees but have four to spread the weight over.
The authors suggest a honeycomb bone structure for lightness, but there's no precedent for a true birdlike honeycomb structure in mammals: you have to postulate a long line of evolution we know nothing about for a change this radical. It seems a stretch even though, given that we have nothing of G. blacki but fossil jaws and teeth and the entire fossil record of the modern species of chimpanzee and gorilla could be held in a man's two hands, our picture of primate ancestry is a long way from complete.
Gigantopithecus is viewed by anthropologists, almost unanimously, as a heavily built knuckle-walker. If this is correct, it would take a lot of evolving to get to any sort of upright ape and a lot more for the True Giant. Giganto's gorilla-like posture is basically implied from the sheer size indicated by its sparse fossils, so this common scientific belief does not quite rise to the level of established fact. The late Grover Krantz argued the spread of the fossil jaws indicated upright posture, but leading Giganto expert Russell Ciochon rejected this, and very few people in the scientific community are open to the idea.
Implausibilities and new structures certainly arise in mammals, but scattered eyewitness reports and footprints are not enough to make me take the True Giant possibility seriously. I commend the authors for tackling a difficult subject and sparking debate, and cryptozoologists should read this book for an understanding of the "high end" of unidentified-primate reports.