[Paper] Landscape rules predict optimal superhighways for the first peopling of Sahul

via Nature Human Behaviour, 29 April 2021: An interesting paper modelling the likely routes people took through the New Guinea and the Sahul continent to populate what is Australia today. There also an associated paper from Nature Communications linked below.

Archaeological data and demographic modelling suggest that the peopling of Sahul required substantial populations, occurred rapidly within a few thousand years and encompassed environments ranging from hyper-arid deserts to temperate uplands and tropical rainforests. How this migration occurred and how humans responded to the physical environments they encountered have, however, remained largely speculative. By constructing a high-resolution digital elevation model for Sahul and coupling it with fine-scale viewshed analysis of landscape prominence, least-cost pedestrian travel modelling and high-performance computing, we create over 125 billion potential migratory pathways, whereby the most parsimonious routes traversed emerge. Our analysis revealed several major pathways—superhighways—transecting the continent, that we evaluated using archaeological data. These results suggest that the earliest Australian ancestors adopted a set of fundamental rules shaped by physiological capacity, attraction to visually prominent landscape features and freshwater distribution to maximize survival, even without previous experience of the landscapes they encountered.

Source: Landscape rules predict optimal superhighways for the first peopling of Sahul | Nature Human Behaviour

Stochastic models support rapid peopling of Late Pleistocene Sahul
Nature Commnunications

The peopling of Sahul (the combined continent of Australia and New Guinea) represents the earliest continental migration and settlement event of solely anatomically modern humans, but its patterns and ecological drivers remain largely conceptual in the current literature. We present an advanced stochastic-ecological model to test the relative support for scenarios describing where and when the first humans entered Sahul, and their most probable routes of early settlement. The model supports a dominant entry via the northwest Sahul Shelf first, potentially followed by a second entry through New Guinea, with initial entry most consistent with 50,000 or 75,000 years ago based on comparison with bias-corrected archaeological map layers. The model’s emergent properties predict that peopling of the entire continent occurred rapidly across all ecological environments within 156–208 human generations (4368–5599 years) and at a plausible rate of 0.71–0.92 km year−1. More broadly, our methods and approaches can readily inform other global migration debates, with results supporting an exit of anatomically modern humans from Africa 63,000–90,000 years ago, and the peopling of Eurasia in as little as 12,000–15,000 years via inland routes.

See also:

• We mapped the ‘super-highways’ the First Australians used to cross the ancient land | The Conversation, 30 April 2021
• Mapping the ‘superhighways’ travelled by the first Australians | Flinders University, 29 April 2021
• First Human Inhabitants of Australia Followed “Superhighways” Across the Continent | SciTech Daily, 29 April 2021
• Researchers map ancient ‘superhighways’ used by first Australians | Sydney Morning Herald, 30 April 2021