via Quaternary Science Reviews, 15 January 2024: New archaeological research has uncovered evidence of a massive, now-submerged landmass off northwest Australia, once part of Sahul, which included mainland Australia, Tasmania, and New Guinea. This area, 1.5 times larger than New Zealand, was home to a diverse ecosystem and a vast colony supporting between 50,000 and 500,000 people during the Late Pleistocene. The discovery, made possible through high-resolution bathymetric data analysis, reveals that rising sea levels around 12,000 to 9,000 years ago significantly impacted human settlements, forcing migrations and cultural changes, and suggesting the area’s role in early human expansions.
For most of the period of human occupation of Sahul (the combined Pleistocene landmass of Australia and New Guinea), lower sea levels exposed an extensive area of the northwest of the Australian continent, connecting the Kimberley and Arnhem Land into one vast area. Our analysis of high-resolution bathymetric data shows this now-drowned region existed as an extensive archipelago in Marine Isotope Stage 4, transforming in Marine Isotope Stage 2 into a fully exposed shelf containing an inland sea adjacent to a large freshwater lake. These were encircled by deep gorges and escarpments that likely acted as important resource zones and refugia for human populations at that time. Demographic modelling shows the shelf had a fluctuating potential carrying capacity through Marine Isotope Stages 4–2, with the capability to support 50–500 k people at various times. Two periods of rapid global sea level rise at 14.5–14.1 ka (Meltwater Pulse 1A), and between 12 ka and 9 ka, resulted in the rapid drowning of ∼50% of the Northwest Shelf. This likely caused a retreat of human populations, registering as peaks in occupational intensity at archaeological sites. We contend that the presence of an extensive archipelago on the Northwest Shelf in Marine Isotope Stage 4 facilitated the successful dispersal of the first maritime explorers from Wallacea, creating a familiar environment for their maritime economies to adapt to the vast terrestrial continent of Sahul.
See also:
- Lost ancient colony off coast of Australia that hundreds of thousands once called home discovered | New York Post, 22 Dec 2023
- Lost ancient realm ‘populated by millions of people’ found at bottom of ocean after being ‘drowned’ 18,000 years ago | The Sun, 22 Dec 2023
- What life was like when Australia and New Guinea were one landmass | SBS, 23 Dec 2023
- Australia’s lost ancient colony, where thousands once lived, now found | WION, 24 Dec 2023
