Recently excavated human skulls provide insight into human migration from Southeast Asia to Australia

Somewhere beyond the sea: Human cranial remains from the Lesser Sunda Islands (Alor Island, Indonesia) provide insights on Late Pleistocene peopling of Island Southeast Asia

Sofía C. Samper Carro, Felicity Gilbert, David Bulbeck, Sue O’Connor, Julien Louys, Nigel Spooner, Danielle Questiaux, Lee Arnold, Gilbert Price, Rachel Wood, Mahirta

Summarized by: Lisette E. Melendez. Lisette Melendez is a geology major and astronomy minor at The University of South Florida. She is currently a junior, but has her sights set on going to graduate school for planetary Geology. She loves rocks, space, and everything pink.

What data were used? Newly excavated human remains from three test pits in Tron Bon Lei
(Wallacean Islands, Indonesia) are being compared to human remains from Asia and Australia to test for similarities. Other elements that were found in the excavation include shellfish, fish remains, and fish hooks were used to characterize the living environment.

Methods: This study used dating of various elements and observation of skull traits to estimate ages of the cranial remains. The first element studied was the amount of carbon- 14 in the specimen because carbon-14 can date items up to approximately 50,000 years old. Uranium and Thorium are both elements that are preserved in fossilized teeth and those elements were also measured to reinforce the reliability of the age estimates from carbon. Physical traits of the skull fragments were analyzed to estimate the age and sex of the samples. Age estimation was based on how worn down the teeth were and degree of cranial suture closure (tissues that fuse together as you get older).

The human remains recovered from Tron Bon Lei (Wallacean Islands, Indonesia).

Results: The dating measurements of these Wallacean specimens suggest that the skeletons were buried around 11.5 to 13 thousand years ago, at the end of the Pleistocene Epoch. They are smaller than any of the other cranial remains from Indonesia, Australia, and New Guinea, but the small size of these remains are similar in size to Holocene- age remains, supporting the model that southeastern Indonesian populations were isolated.

Why is this study important? This study helps us unravel the environment of southeast Asia and understand living conditions thousands of years ago.

The big picture: This study shows that the Wallacean islands may be an example of island dwarfing, suggesting that these populations may have been relatively isolated, at least up to the late Pleistocene. Island dwarfing typically occurs when there is a scarce amount of resources on an island, which was only exacerbated by the genetic isolation that occurred on this island.

Citation: Samper Carro, S. C. et al. Somewhere beyond the sea: Human cranial remains from the LesserSunda Islands (Alor Island, Indonesia) provide insights on Late Pleistocene peopling of Island Southeast Asia. J. Hum. Evol. 134, 102638 (2019). Online.

Advertisements

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.