via Eureka Alerts, 20 June 2019: Demographic models explained in a couple of recent papers in Nature (see links below) posit that human migration to Australia was a deliberate a large logistical endeavour, requiring a single event of 1,300 migrants, or successive waves involving hundreds of people at each time.
The team of multidisciplinary researchers from CABAH and the CSRIO set out to establish the most likely route travelled to reach the ancient mega-continent, known as Sahul (New Guinea, Australia and Tasmania joined at times of low sea level).
“We developed demographic models to determine which island-hopping route ancient people most likely took,” said CABAH’s Professor Corey Bradshaw, from Flinders University.
“A northern route connecting the islands of Mangoli, Buru, and Seram into West Papua New Guinea would probably have been easiest to navigate and survive. This route was easiest when compared to the southern route from Timor that leads to the now-drowned Sahul Shelf in the modern-day Kimberley region.”
The researchers also used complex mathematical modelling — considering factors including fertility, longevity, past climate conditions, and other ecological principles — to calculate the numbers of people required for the population as a whole to survive.
The simulations indicate that at least 1300 people arrived in either a single migration event or smaller, successive waves averaging at least 130 people every 70 years or so, over the course of about 700 years.