Man was born as the only few animals on earth that can walk for hundred of kilometer on our two legs. By walking on two legs, now our hands are free to build and use man-made tools to dominate every earth ecosystem from the high mountain of Everest to the North Pole and Australia. We only get trapped in Australia after the land bridge from Vietnam to Australia was sunken by the random earth tectonic plate movements.
Before the landbridge of South East Asia was sunken, the early human from Africa and Yellow River delta was able to reach Australia on foot and left many offsprings and genetic mark in this far corner of the Earth.
This seems to be misfortune from the almighty nature results in billion barrels of oil and gas reserves burried under the seabed of South East Asia. Now the South East Asian humans will not have to walk for hundred kilometers again but can move around freely on their vehicles and cook their meal cheaply from these tropical forrests compressed by deep ocean water.
Before we invented Gasoline and the Combustion Engine, the early human was already smart enough to invent the sailboats to take advantages of free form of energy from nature to travel across lakes and ocean. Ocean travel is much more dangerous and lower throughput than through the sunken land bridge but few human tribes still make it to their Australia, New Zeland and Haiwaii.
The tropical hurricanes of South East Asia are too strong for the level of ocean trades that we would see in the Mediterranean but still cannot stop the merchants from Yangzte and Yellow river delta to travel South and the merchants from Quy Nhon, Vietnam to travel West to create an ocean trade network across the sunken ocean lake of South East Asia.
With the Mediterranean and Baltic much calmer sea though, the Western explorers was able to develop much more advanced long distances ocean vessel and made the final genetic marks in Australia and other Pacifics islands.
First the Hispanic Naval Colonial Empire, and later on the American naval colonial empires built mega settlements on these Pacifics Islands with the Philipines and Australia being two largest Western forward military bases in South East Asia.
Till the modern days, the Vietnamese merchants and the Hispanic explorers seem to leave the most amount of their genetic marks on the facial features of Philipine city mayors and residents.