Scott Cane wrote in 2013 that the first wave may have been prompted by the eruption of Toba, and if they arrived around 70,000 years ago, they could have crossed the water from Timor, when the sea level was low – but if they came later, around 50,000 years ago, a more likely route would be through the Moluccas to New Guinea. Given that the likely landfall regions have been under around 50 metres of water for the last 15,000 years, it is unlikely that the timing will ever be established with certainty.