Early Palaeolithic on the Greek Islands?

Humans evolved in Africa and colonized Eurasia in successive adaptive radiations, establishing themselves in Europe ca. one million years ago. It is assumed that these dispersals were by land through southwest Asia, or secondarily across the Strait of Gibraltar, because early hominins lacked the cognitive faculties and technical skills needed to cross the open Mediterranean. Such crossings are thought to have occurred only at the end of the Pleistocene, after ca. 11,000 years ago. This reasoning is challenged by the presence of early Palaeolithic artifacts on the Greek islands, suggesting that hominins made sea-crossings more than 130,000 years ago, and indicating that the Mediterranean-and by implication other seas-were at times open roads rather than barriers to hominin dispersals.