The process, biotic impact, and global implications of the human colonization of Sahul about 47,000 years ago

Comprehensive review of archaeological data shows that Sahul (Pleistocene Australia-New Guinea) was first occupied by humans ca. 47 ka (47,000 years ago); evidence for earlier arrival is weak. Colonizing populations remained low - perhaps two orders of magnitude below those estimated at European contact - for many millennia, and were long restricted to relatively favorable habitats. Though human arrival coincided with changes in native flora and fauna, these were mainly the products of climatic factors, not human interference. The genetic makeup of founding populations and their arrival date are consistent with the Late Dispersal Model of anatomically modern humans beyond SW Asia, beginning ca. 50 ka. Early Dispersal Models (120-70 ka) are not refuted, but draw no support from the Sahul record as currently understood.