If Big Foot exists this is probably what he is or a close relative. Even though the scientific community believes it is extinct, I think that some of them have still survived and are what we now refer to as Big Foot, Yeti, Skunk Ape, Etc.
Gigantopithecus:
Gigantopithecus was the largest of the primates
During the Pleistocene Era (1.8 million to 10,000 years ago) large mammals ruled the Earth. One of these mammals was the great ape Gigantopithecus.
Gigantopithecus is known to have lived in what is now China and Southeast Asia. (In fact he was discovered, by Professor Gustav von Koenigswald, when the professor bought a set of fossil teeth from a Chinese druggist selling what he claimed were "dragon's teeth" for medicinal purposes.)
Gigantopithecus was the largest primate that ever walked the Earth. He would have risen 9 to 10 feet high if he choose to stand up on only his hind legs, and probably weighed about 600 lbs (A few scientists suggest the largest of the males might have weighted almost 1,200 lbs.). In comparison, the largest gorilla stands only 6 feet tall and weighs about 300 to 400 lbs.
Both today’s gorilla and Gigantopithecus probably used their arms and knuckles to move about in quadruped fashion. Though Gigantopithecus sounds like a terror he probably was a very gentle and retiring vegetarian, if we can use Mountain Gorilla behavior as a guide. Gorilla's, despite inaccurate stories about them, are fairly shy creatures that only put on aggressive displays of chest beating and snarling when their territory is threatened.
Gigantopithecus actually arose before the start of the Pleistocene Era (perhaps 13 million years ago) and went extinct about halfway through (500,000 years ago) the ice age before the other giant mammals did. Exactly why he went extinct is unknown, but it probably was due to changes in the climate to which Gigantopithecus was not able to adapt.
Some suggest that Gigantopithecus is not extinct, but is hiding in remote areas of the Himalaya Mountains or the forests of North-West America. Could a Gigantopithecus, or his descendants, be the source of the Yeti or Bigfoot tales?
http://www.bfro.net/REF/THEORIES/MJM/whatrtha.asp
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