Nelumbo: [Article] Hominins on Flores, Indonesia, by one million years ago.

Nature advance online publication 17 March 2010.

Adam Brumm1, Gitte M. Jensen2, Gert D. van den Bergh1,3, Michael J. Morwood1, Iwan Kurniawan4, Fachroel Aziz4 & Michael Storey2.

1.Centre for Archaeological Science, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia.

2.Quaternary Dating Laboratory, Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, DK-4000 Roskilde, Denmark.

3.Naturalis, the National Museum of Natural History, 2333 CR Leiden, The Netherlands.

4.Geological Survey Institute, Bandung 40122, Republic of Indonesia.

Correspondence to: Adam Brumm1. Correspondence and requests for materials should be addressed to A.B.

Abstract

Previous excavations at Mata Menge and Boa Lesa in the Soa Basin of Flores, Indonesia, recovered stone artefacts in association with fossilized remains of the large-bodied Stegodon florensis florensis. Zircon fission-track ages from these sites indicated that hominins had colonized the island by 0.88 ± 0.07 million years (Myr) ago6. Here we describe the contents, context and age of Wolo Sege, a recently discovered archaeological site in the Soa Basin that has in situ stone artefacts and that lies stratigraphically below Mata Menge and immediately above the basement breccias of the basin. We show using 40Ar/39Ar dating that an ignimbrite overlying the artefact layers at Wolo Sege was erupted 1.02 ± 0.02 Myr ago, providing a new minimum age for hominins on Flores. This predates the disappearance from the Soa Basin of ‘pygmy’ Stegodon sondaari and Geochelone spp. (giant tortoise), as evident at the nearby site of Tangi Talo, which has been dated to 0.90 ± 0.07 Myr ago10. It now seems that this extirpation or possible extinction event and the associated faunal turnover were the result of natural processes rather than the arrival of hominins9. It also appears that the volcanic and fluvio-lacustrine deposits infilling the Soa Basin may not be old enough to register the initial arrival of hominins on the island.

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John Roach | National Geographic News | March 17, 2010

"Hobbits" Had Million-Year History on Island?

Newfound stone tools suggest the evolutionary history of the "hobbits" on the Indonesian island of Flores stretches back a million years, a new study says—200,000 years longer than previously thought.

The hobbit mystery was sparked by the 2004 discovery of bones on Flores that belonged to a three-foot-tall (one-meter-tall), 55-pound (25-kilogram) female with a grapefruit-size brain.

The tiny, hobbit-like creature—controversially dubbed a new human species, Homo floresiensis—persisted on the remote island until about 18,000 years ago, even as "modern" humans spread around the world, experts say.

Found in million-year-old volcanic sediments, the newly discovered tools are "simple sharp-edged flakes" like those found at nearby sites on Flores—sites dated to later time periods but also associated with hobbits and their ancestors—said study co-leader Adam Brumm, an archaeologist at the University of Wollongong in Australia, via e-mail.

The finding implies that a culture of stone tool wielding ancient humans, with origins in Africa, survived on the island for much longer than previously believed, according to the new research, published online today by the journal Nature.

"That's exciting," because it suggests that by a million years ago, early humans had covered more ground on their exodus from Africa than previously thought, said paleontologist Chris Stringer of the Natural History Museum of London, who wasn't involved in the new study.

(Read "Flores Find: The People Time Forgot" in National Geographic magazine.)

Hobbit Ancestors off the Hook?

The stone-and-bone record had suggested that the hobbits' ancestors—perhaps upright-walking-but-small-brained Homo erectus—left Africa about 1.5 million years ago and reached Flores by 880,000 years ago.

(... Read the full article here)