Wednesday, March 12, 2008

Pacific Menehune traditions: new "small people" in Palau

Researchers have discovered a clan of Menehune-sized humans in caves on the island of Palau.

It is the second recent example in the Pacific of what appears to be a miniature race.

(Image: Views of adult skulls found in the Palau caves. Credit: PLoS One.)

The previous finding—reported in 2004—on the Indonesian island of Flores, was of a group of small people, who have been described as a separate species from humans, under the name Homo floresiensis. (As opposed to modern humans, Homo sapiens.)

It raises the question of whether the actual existence of miniature people in the Pacific may have generated the traditions in the Islands of a race of small forest people, among them the Hawaiian Menehune. There have been no discoveries of similarly small human-like remains in Hawai'i.

Palau lies in western Micronesia. The Hawaiian voyaging canoe Hokule'a visited Palau in 2007 on its extended voyage through the eastern Pacific and on to Japan.

The new Palau finding was published in the online journal PloS One, under the title, “Small-Bodied Humans from Palau, Micronesia.” The authors are Lee Berger and Bonita De Klerk of South Africa's Institute for Human Origins and the Bernard Price Institute for Palaeontology, School of GeoSciences, University of the Witwatersrand, along with Steven Churchill of Duke University's Department of Biological Anthropology and Anatomy, and Rhonda Quinn of Rutgers University's Department of Earth and Planetary Sciences.

The authors do not suggest that the Palau samples necessarily represent a different species from humans. Rather, they argue that these might be pygmies—humans whose size has diminished over time, just as other species can sometimes dramatically change size in island environments.

But there are odd things about the findings.

“First, individuals from the older time horizons are small in body size even relative to 'pygmoid' populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo,” they write.

The remains were found in limestone cave environments in the rock islands of Palau. The small individuals represent remains found in two separate burial caves. The caves apparently were only used for burials, since there was no associated material suggesting they were also habitation caves.

And they appear to come from a period well after normal-sized humans first arrived at Palau, which is estimated at 3,000 to 4,500 years ago. Radiocarbon dates on the bone of the Palau Menehune suggested the miniature individuals lived between 1420 and 2890 years ago, or roughly 900 BC to 600 AD.

(The Flores remains are graybeards by comparison—well in excess of 10,000 years old.)

Wave action or other disturbance had moved the Palau bones around, and the researchers were unable to recover complete skeletal remains. They cautioned that “these limitations make it impossible for us to make definitive statements about critical aspects of skeletal morphology in these ancient Palauans—namely brain size and body proportions.”

But they were able to determine that while a few of the remains were of children, many were of mature individuals. And from what they found, they concluded that some of the individuals when alive may have weighed from less than 70 to nearly 100 pounds, that they had small faces, and brains that are the smaller end of the normal range for humans.

The Palau small folks were similar in some ways to the Flores “hobbits,” but not identical to them.

Scientists left many of the remains in place, encased in hardened sediment, and they said further investigation might reveal more about the Palauan small people.

It is clear that under certain circumstances, forms of life can dramatically change size. Sometimes they can get larger, like sheep-sized Hawaiian flightless ducks that evolved from small migrant flying ducks. And sometimes, things shrink.

Among humans, this is not unknown.

“Pygmy populations are known from mainland tropical forests and tropical island settings in Africa and Southeast Asia, reflecting parallel cases of dwarfing in response to the combined factors of relative genetic isolation, a reduced resource base, hot and humid climates, hilly topography, thick undergrowth of vegetation, and (in certain island contexts) an absence of terrestrial predators,” the authors of “Small-Bodied Humans” write.

Their conclusion suggests that the Flores Menehune and the Palau Menehune may simply represent examples of what happens to humans in certain difficult environmental situations:
“Based on the evidence from Palau, we hypothesize that reduction in the size of the face and chin, large dental size and other features noted here may in some cases be correlates of extreme body size reduction in H. sapiens. These features when seen in Flores may be best explained as correlates of small body size in an island adaptation, regardless of taxonomic affinity. Under any circumstances the Palauan sample supports at least the possibility that the Flores hominins are simply an island adapted population of H. sapiens, perhaps with some individuals expressing congenital abnormalities.”

The paper is online at www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001780#pone.0001780-Brown1.

© 2007 Jan W. TenBruggencate