Gigantopithecus

compFor thousands of years, Chinese pharmacists have used fossils as ingredients in potions in curative purposes. In a pharmacy, in Hong Kong in 1935, the German paleoanthropologist Ralph von Koenigswald came across a large fossil primate molar that did not belong to any known species. Over the next four years he searched further in Hong Kong and Guangzhou (Canton) and found three more of the oversize teeth, thereby establishing the existence of an extinct ape, the largest primate ever to roam the earth. He named the genus Gigantopithecus, meaning “gigantic ape,” and the species blacki, in honor of his late friend and colleague Davidson Black.
At the time of the discovery, during the 1930s, von Koenigswald was working in Java, searching fossils of human ancestors and their relatives. China’s unique fossil shops had already played a major role in tracking down Homo erectus, which lived in Asia between about one million and 300,000 years ago. Homo erectus remains were first unearthed in Java in the 1890s, but pursuit of the source of “dragon bones” (this is the name given by Chinese pharmacists to fossils having curative properties) subsequently led to a system of fossil-filled crevices and caverns near the town of Zhoukoudian (Choukoutien), thirty miles from Beijing. There, in 1929, a team of Chinese and Western scientists discovered the first of a series of Homo erectus skulls that became world famous as “Peking man.”
The original fossils of Peking man disappeared during the confusion of World War II after they were described and cast by anatomist Franz Weidenreich. Von Koenigswald was taken prisoner by the Japanese in Java and his unique collection of Gigantopithecus teeth spent the war years in a milk bottle buried in a friend’s backyard on the island.jaw
Weidenreich retreated from Beijing to the American Museum of Natural History in New York and studied plaster casts of the four teeth. Because of the unusually large size of a few of the Homo erectus specimens from Java, Weidenreich believed there had been a period of gigantism in human evolution, and that modern humans were the diminutive descendants of these giants. In “Apes, Giants, and Man”, published in 1946, he claimed that the Gigantopithecus teeth were humanlike, and that von Koenigswald had been mistaken in considering the animal an ape rather than a human species.
Weidenreich’s views became widely accepted until the 1950s. Then with the establishment in Beijing of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese paleontologists began to search for the source of the Gigantopithecus fossils. Two researchers of the Peking man expedition, Pei Wenzhong and Jia Lanpo, leaded a team that visited the warehouses that supplied all the apothecary shops in China with “dragon bones and teeth”. They found numerous fossils in Nanning, the capital of Guangxi Province. There they divided into two teams: one, led by Pei, headed north; the other, led by Jia, went south.
Jia’s team went to southernmost Guangxi, a karstic, or eroded limestone, region of great rock towers riddled with caves. In the town of Daxin, which the local people said was the source of all the fossils, they were directed to an old woman who had, in her house, a bamboo tray full of fossils. One of them was a Gigantopithecus tooth. She pointed out a very tall rock tower, described by Jia as “a hundred meters straight up – almost falling over, it was so steep.” The mouth of a cave was clearly visible behind a screen of brush. Jia found in the cave a Gigantopithecus tooth embedded in a hard, reddish matrix, the first time that a paleontologist had discovered a fossil of Gigantopithecus in a geological context.
Meanwhile, Pei was making a more momentous discovery to the north. Word had reached the scientists of a giant jawbone discovered by an old farmer in 1956 at a cave site called Liucheng. When Pei saw the fossil, he was able to identify it at once as the jawbone of Gigantopithecus, because it had all but three of its teeth still attached. On a second visit, in 1957, Pei’s team discovered the first Gigantopithecus jawbone in place, in a very hard deposit resembling red clay. Another was excavated in 1958. One of the jawbones was extraordinarily large; presumably, it belonged to an adult male, while the other two were thought to be from an adult female and a juvenile.
Pei’s group also discovered nearly a thousand Gigantopithecus teeth and numerous other mammalian specimens, including some unusual dwarf varieties. Among them was a short-muzzled panda half the size of the living giant panda. Chinese scientists have recently suggested that this dwarf species was a direct ancestor of the modern one.
The next step forward came in 1965 with the discovery of twelve Gigantopithecus teeth at Wuming, a few hours’ drive north of Nanning. These teeth were significantly larger than their counterparts from Liucheng, and the other animal fossils found with them suggested that the site was considerably younger (current estimates are that Liucheng is one million years old and that Wuming is between 300,000 and 400,000 years old). This suggested, first, that Gigantopithecus was around as a species for a considerable period, and second, that it may have become larger as the species evolved. This is a trend seen in other large mammals that evolved during the Pleistocene epoch, 1.8 million to 12,000 years ago.
A striking confirmation of both points was the discovery three years later that a smaller, earlier form of the giant ape had once inhabited northern India. In 1968, a farmer came forward with three pieces of a jawbone he had found twenty-four years before, when he was a boy of twelve working in his father’s field. The specimen was identified by primatologist Elwyn Simons as belonging to a distinct species, Gigantopithecus giganteus, about half the size of Gigantopithecus blacki. The new species was not only smaller but also more ancient, coming from sediments that have been dated (by paleomagnetic reversals) to about 6.3 million years ago.
The discovery of the jaws resolved, at least for most scientists, any doubts that the creature was apelike and not, as Weidenreich had argued, humanlike. Based on the fossils, Gigantopithecus is now placed among the Asian apes, a descendant, along with the orangutan, of the earlier ape ancestor Sivapithecus, best known from an 8-million-year-old skull discovered in Pakistan. Its size and ape affiliation suggest Gigantopithecus was a ground-dwelling, fist-walking creature.
While more teeth of the extinct ape have been found, no other bones have turned up. Based only on the jaws and teeth, however, an attempt can be made to reconstruct both the animal and its way of life. The jaws are deep (top to bottom) and very thick. The molars are low-crowned and flat, with very thick enamel caps suitable for heavy grinding. The premolars are broad and flat and resemble molars. The canine teeth are not sharp and pointed but shaped more like what one would expect premolars to look like, while the incisors are small, peglike, and closely packed. The canines and incisors together form a specialized cutting tool, most similar to what is found in some present-day tree sloths and in the extinct giant ground sloth. The features of the teeth, combined with the massive, robust jaws, lead to the inevitable conclusion that the animal was adapted to the consumption of tough, fibrous foods by cutting, crushing, and grinding them.
As a rule, large herbivores subsist on diets of coarse leaves and grasses, which are low in nutritional value but typically available in very large quantities. (Large animals succeed with this regime partly because their metabolic requirements are relatively low, in terms of energy required per unit of body mass.) One suggestion is that Gigantopithecus, or at least the larger species in China, was adapted, like the giant panda, to a diet of bamboo, the giant grass abundant in the region. The jaws of Gigantopithecus and the giant panda, if set side by side with the jawbones of, say, the gorilla and the grizzly bear, appear thicker, deeper, and more massive. These differences reflect the specialized diet of the panda (and, by inference, of Gigantopithecus) compared with the much more general diet of the gorilla and grizzly.
A further similarity between Gigantopithecus and the giant panda is a high incidence of tooth cavities. Wu Rukang, in an encyclopedic survey of the Gigantopithecus teeth in China, found cavities present in 11 percent of them – an unusually high rate for an ape, but more or less equivalent to the rate of dental cavities in the fossil remains of the giant panda. Another Chinese researcher, Zhang Yinyun, has reported a high incidence of hypoplasia – pitting in the tooth enamel that indicates periods of arrested development. These may be a result of disease or food shortage. While no certain conclusion may be drawn, we do know that bamboo is subject to periodic die-offs, which produce food shortages that threaten the survival of the giant panda.
A more direct line of evidence regarding the diet of Gigantopithecus was looking at the teeth for adhering phytoliths, microscopic pieces of silica found in many plants. The existence of phytoliths has been known since the early nineteenth century, and scientists had already successfully looked for them on stone tools, to which they apparently bond physically by the combined action of friction and moisture. But it was the first time anyone looked for them on fossil teeth.
Four teeth were borrowed for study from the British Museum (Natural History) and the Senckenberg Natural History Museum in Frankfurt: an upper incisor, lower canine, lower premolar, and lower molar. After the teeth were cleaned, they were examined under a scanning electron microscope at the University of Iowa by Smithsonian paleoecologist Dolores Piperno. At least thirty phytoliths were found on the teeth, most of them on the molar.
More than half of the phytoliths observed were long and needlelike and could be attributed to the vegetative part of grasses, possibly bamboo. The rest were conical or hat shaped, attributable to the fruits and seeds of dicotyledons. This proved that Gigantopithecus had a varied diet, but it is possible that bamboo to have been its staple food.
An outstanding characteristic of giant herbivores is their extreme slowness. They have no particular need of speed: their size and thick skins protect them from predators, and of course their feeding habits require no more of them than that they move from place to place as they systematically denude the landscape of vegetation. Furthermore, they are usually stuffed full of bulky food to digest, which tends to produce inertia. Gigantopithecus probably followed this pattern.
The adult males of the giant ape were much larger than the females. Australian anatomist Charles Oxnard statistically analyzed 735 teeth of Gigantopithecus that were complete enough to be measured accurately. He found that they divided neatly into two size groups of equal number, which he interpreted to represent the males and females in the population. The contrast was greater than that seen in any living primate species, including the gorilla and the orangutan, two species in which the male is substantially bigger than the female. In Gigantopithecus, the difference in tooth size between the sexes may represent strong competition among males for mates – a clue to the species’ social behavior.
To gain a more complete image of what the giant ape looked like, the help of Bill Munns was sought, who creates highly realistic, life-size models of existing endangered primates – gorillas, orangutans, and the Chinese golden monkey – for zoos and educational institutions. Based on the jaws and teeth, and using the proportions of the skulls of existing great apes, it was estimated that the average male Gigantopithecus had a skull that measured eighteen inches from the bottom of the jaw to the highest point of the sagittal crest (a male gorilla, for comparison, has a skull ten inches high).
The next step was to project a hypothetical skeleton from the hypothetical skull. For this purpose Munns used as references two of the largest terrestrial primates known: one modern, the gorilla, and one from the fossil record, the extinct giant baboon Theropithecus oswaldi. In determining the size of Gigantopithecus, we felt it necessary to scale the body back a bit, so as not to be influenced too much by the giant ape’s extraordinarily deep and thickened mandible. Nevertheless, given that the average male silverback gorilla is about six feet tall (standing erect) and weighs in at 400 pounds (181 kg), Munns calculated that the average Gigantopithecus male was more than ten feet tall and weighed as much as 1,200 pounds (544 kg)- comparable to a large male polar bear.
One intriguing question is what contact humans’ remote ancestor, Homo erectus, may have had with the giant ape. That the two coexisted for some time in the same region is supported by direct evidence. In 1965, Vietnamese paleontologists discovered the remains of both creatures at Tham Khuyen, a cave site in Lang Son Province, near the Chinese border.

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