Meganthropus

Meganthropus
Homo erectus palaeojavanicus
Temporal range: Pleistocene
Pithecanthropus robustus, Sangiran Museum, Sragen, Indonesia
Fossil
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Genus: Homo?
Species: †H. erectus?
Subspecies: †H. e. palaeojavanicus?
Trinomial name
Homo erectus palaeojavanicus?

Meganthropus is a name commonly given to several large jaw and skull fragments found at the Sangiran site near Surakarta in Central Java, Indonesia. The original scientific name was Meganthropus palaeojavanicus, and while it is commonly considered invalid today, the genus name has survived as something of an informal nickname for the fossils.

As of 2005, the taxonomy and phylogeny for the specimens are still uncertain, although most paleoanthropologists consider them related to Homo erectus in some way. However, the names Homo palaeojavanicus and even Australopithecus palaeojavanicus are sometimes used as well, indicating the classification uncertainty. Of particular interest is that the finds were sometimes regarded as those of giants, although that is unsubstantiated.

After the discovery of a robust skull in Swartkrans in 1948 (SK48), the name Meganthropus africanus was briefly applied. However, that specimen is now formally known as Paranthropus robustus and the earlier name is a junior synonym.

Some of these finds were accompanied by evidence of tool use similar to that of Homo erectus. This is the reason Meganthropus is often linked with that species as H. e. palaeojavanicus.

Fossil finds

The number of fossil finds has been relatively small, and it is a distinct possibility that they are a paraphyletic assemblage. Due to this, they will be discussed in detail separately.

Meganthropus A/Sangiran 6

This large jaw fragment was first found in 1941 by von Koenigswald. Koenigswald was captured by the Japanese in World War II, but managed to send a cast of the jaw to Franz Weidenreich. Weidenreich described and named the specimen in 1945, and was struck by its size, as it was the largest hominid jaw then known. The jaw was roughly the same height as a gorilla's, but had a different form. Whereas in anthropoids the mandible (=jaw) has its greatest height at the symphysis, that is, where the two rami of the lower jaw meet, this is not the case in Sangiran 6, where the greatest height is seen at about the position of the first molar (M1).

Weidenreich considered acromegalic gigantism, but ruled it out for not having typical features such as an exaggerated chin and small teeth compared to the jaw's size. Weidenreich never made a direct size estimate of the hominid it came from, but said it was 2/3 the size of Gigantopithecus, which was twice as large as a gorilla, which would make it somewhere around 8 feet (2.44 m) tall and approximately 400 to 600 lbs (181 – 272 kg) if scaled on the same proportions as a robust man or erect hominid. In his book Apes, Giants, and Man, Weidenreich states the following:

Therefore, it may not be too far from the truth if we suggest the Java giant [Meganthropus] was much bigger than any living gorilla and that the Chinese giant [Gigantopithecus] was correspondingly bigger than the Java giant – that is, one-and-a-half times as large as the Java giant, and twice as large as a male gorilla.

The jawbone was apparently used in part of Grover Krantz's skull reconstruction, which was only 8.5 inches (21 centimeters) tall.

Meganthropus B/Sangiran 8

This was another jaw fragment described by Marks in 1953. It was around the same size and shape as the original mandible, but it was also severely damaged. Recent work by a Japanese/Indonesian team repaired the fossil, which was an adult, and showed it to be smaller than known specimens of H. erectus. Curiously, the specimen did retain several traits unique to the first mandibular find and not known in H. erectus. No size estimates have been made yet.

Meganthropus C/Sangiran 33/BK 7905

This jaw fragment was discovered in 1979, and has some characteristics in common with previous mandible finds. Its connection with Meganthropus appears to be the most tenuous out of the mandibular discoveries.

Meganthropus D

This mandible and ramus was acquired by Sartono in 1993, and has been dated to between 1.4 and 0.9 million years ago. The ramus portion is badly damaged, but the mandible fragment appears relatively unharmed, although details of the teeth have been lost. It is slightly smaller than Meganthropus A and very similar in shape. Sartono, Tyler, and Krantz agreed that Meganthropus A and D were very likely to be representations of the same species, whatever it turns out to be.

Meganthropus I/Sangiran 27

Tyler described this specimen as being a nearly complete but crushed cranium within the size limit of Meganthropus and outside the (assumed) limit of H. erectus. The specimen was unusual for having a double temporal ridge (sagittal crest), which almost meets at the top of the cranium, and a heavily thickened nuchal ridge.

Meganthropus II/Sangiran 31

This skull fragment was first described by Sartono in 1982. Tyler's analysis came to the conclusion that it was out of the normal range of H. erectus. The cranium was deeper, lower vaulted, and wider than any specimen previously recovered. It had the same double sagittal crest or double temporal ridge with a cranial capacity of around 800–1000cc. Since its presentation at the AAPA meeting in 1993, Tyler's reconstruction of Sangiran 31 has been accepted by most authorities.

As with most fossils it was heavily damaged, but given the completeness of the post facial cranium the chances of error in its reconstruction are very small. Tyler's accepted reconstruction of Sangiran 31 shows a double temporal ridge. In either case, the temporal muscles extend to the top of the parietal where they almost join. There are no other Homo erectus specimens that exhibit this trait. Krantz's reconstruction of Sangiran 31 as a giant Homo habilis has been found to be dubious at best.

Meganthropus III

This is another fossil with only tenuous ties to Meganthropus. It is what seems to be the posterior part of a hominid cranium, measuring about 10 to 7 cm. It has been described by Tyler (1996), who found that the occipital angle of the whole cranium must have been at about 120°, which according to him would be out of the known range of Homo erectus, the latter having a much more angled occiput. His interpretation of the cranial fragment was, however, questioned by other authorities, to include doubts that the fragment was actually the part of a skull that Tyler had thought it to be.

Scientific interpretation

H. erectus

The majority of paleoanthropologists consider the Meganthropus fossil remains as falling within the variation of H. erectus. As Kaifu et al. (2005) note: "If we take the conservative standpoint that all earlier Homo populations that are sufficiently derived from African early Homo belong to H. erectus, the Grenzbank/Sangiran group is allocated to a primitive group of this species." However some argue that the Meganthropus fossils warrant a separate species or H. erectus subspecies, proposing the names H. palaeojavanicus or H. e. palaeojavanicus based on their overall primitiveness, such as low cranial capacity (Tyler, 2001). Against this view, Wolpoff (1999) argues for strong similarities between earlier and later Javanese fossils and no species nor subspecies distinction.

Australopithecine

Robinson (1953) first suggested that Meganthropus (based on the Sangiran 6 mandibular fragment) could be a Southeast Asian representative of robust australopithecines. A similar theory was proposed by Krantz (1975) who argued that Sangiran 6 is: "entirely outside the possible size range of Homo erectus and should be classed as Australopithecus africanus" (i.e. gracile as opposed to robust australopithecine). According to Koenigswald (1973) both robust and gracile australopithecine traits can be found in Sangiran 6: "In certain respects the lower jaw of Meganthropus combines characteristics of A. africanus (premolars) with those of A. robustus (size)."

A study by Orban-Segebarth & Procureur (1983) of the Sangiran 6 mandible also concluded: "Asiatic Meganthropus 'Sangiran 6' has marked australopithecoid traits" but Kramer and Konigsberg (1994) challenge this view. According to Cartmill and Smith (2009): "there is no compelling reason to remove any of the 'Meganthropus' specimens from H. erectus".

Extreme claims

Meganthropus has been the target of numerous extreme claims, none of which is supported by peer-reviewed authors since the late 20th century. Perhaps the most common claim is that Meganthropus was a giant; one unsourced claim estimated they were 9 feet (2.75 m) tall and 750 to 1000 pounds (340 to 450 kilograms).

O.D. von Engeln [and] Kenneth E. Caster. mentioned that " Another astounding discovery is that of human teeth in China and Java of such size as to suggest a period of gigantism in human evolution. If the teeth can be accepted as indicative, these giant men stood 8 to 10 feet tall and weighed perhaps 600 to 700 pounds!" Von Engeln, O. D.; Caster, Kenneth E. (1952). Geology. : McGraw-Hill Book Co.Inc.(pages 411-412)

    No exact height has been published in a peer-reviewed journal since the late 20th century, and none gives an indication of Meganthropus being substantially larger than H. erectus. However, earlier estimates from the 1940s and 1950s, based primarily on the very large Sangiran No. 6 jaw fragment, led Prof. Franz Weidenreich, and several other anthropologists to conclude Meganthropus was a giant, and substantially larger than any H. erectus, perhaps on the order of 2 to 4 times the body mass. Perhaps as expression of this theory, Von Koenigswald and Weidenreich named the taxon in 1942, "Meganthropus palaeojavanicus", which in Neo-Latin translates to "great or large man of ancient Java".

    There have been some rumors of post-cranial material, but those have either yet to be published or belong to H. erectus. Reports, most if not all apparently from Australian researcher Rex Gilroy, place Meganthropus in Australia. He associates it with giant tools and even modern day reports. But, almost all paleoanthropologists maintain that Meganthropus is known only from central Java. In similar non-peer-reviewed claims, some Bigfoot researchers claim that Bigfoot is a modern Meganthropus.

    Sources

    References

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