Other land bridges around the world have been created and re-flooded in the same way : approximately 14,000 years ago , mainland Australia was linked to both New Guinea and Tasmania ; the British Isles were an extension of continental Europe via the dry bed of the English Channel ; and the dry basin of the South China Sea linked Sumatra , Java and Borneo to the Asian mainland . Other land bridges around the world have emerged and disappeared in the same way : approximately 14,000 years ago , mainland Australia was linked to both New Guinea and Tasmania ; the British Isles formed an extension of continental Europe via the dry bed of the English Channel ; and the dry basin of the South China Sea linked Sumatra , Java and Borneo to the Asian mainland .