Age of the earliest known hominids in Java, Indonesia
From: Science(Vol. 263, Issue 5150.)
Publisher: American Association for the Advancement of Science
Document Type: Article
Length: 3,586 words
[Ar.sup.40]/[Ar.sup 39] laser-incremental heating of hornblende separated from pumice recovered at two hominid sites in Java, Indonesia, has yielded well-defined plateaus with weighted mean ages of 1.81 [+ or -] 0.04 and 1.66 [+ or -] 0.04 million years ago (Ma). The homonid fossils, a juvenile calvaria of Phithecanthropus and a partial face and cranial fragments of Meganthropus, commonly considered part of the Asian Homo erectus hypodigm, are at least 0.6 million years older than fossils referred to as Homo erectus (OH-9)from Olduvai Gorge, Tanzania, and comparable in age with the oldest Koobi Fora Homo cf. erectus (Homo ergaster) in Kenya. These ages lend further credence to the view that Homo erectus may have evolved outside of Africa. If the ancestor of Homo erectus ventured out of Africa before 1.8 Ma, the dispersal would have predated the advent of the Acheulean culture at 1.4 Ma, possibly explaining the absence of these characteristic stone cleavers and hand axes in East Asia.