Outside of Africa, Australia holds some of modern humans’ earliest archeological evidence, with relics dating back to about 45,000 years ago. In other words, Australian aboriginals are the oldest continuous population of humans on the planet, besides those found in Africa. But these populations did not remain quite as isolated as researchers originally thought.

Anthropologists and historians always assumed that from the time the first human settlers stumbled upon Australia to the moment European sailors arrived in the late 1800s, Australia remained unknown to the rest of the world. But new research refutes this commonly held belief with evidence of substantial gene flow between Australian and Indian populations millennia ago.