Homo erectus, an extinct human ancestor is an important part of our evolutionary history. Emerging at least 2 million years ago, it was the first species to develop human-like body proportions and the first human species to migrate out of Africa, eventually finding its way to Southeast Asia. Homo erectus was first discovered in Java and was known as “Java Man” until the species was officially renamed. Long thought to have been isolated on the island of Java, two fossil fragments of a Homo erectus skull—which surfaced with recent ocean dredging in preparation for the construction of an artificial island—revealed that this hominin species migrated and spread throughout the islands when they could still walk over bridges of land.

The drowned Sundaland

According to four studies published in Quaternary Environments and Human, by archaeologist Harold Berghuis and his team, these lost lands, called drowned Sundaland, were once vast open plains interspersed with rivers around 140,000 years ago.

During the glacial period that chilled the Earth 140,000 years ago, sea levels in the Indonesian region of Sundaland were low enough for present-day islands to tower like mountain ranges with a lowland savannah stretching between them. It was an expanse of mostly dry grasslands with strips of forest edging the rivers, and animals like crocodiles, river sharks, elephants, hippos, rhinos, and Komodo dragons flourished in the region.

Hunting and Cultural exchanges

Berghuis and his team argue that these ancient rivers provided not just water, but sustenance through fruit-bearing trees, fish, shellfish, and edible plants. Tool marks on bones Fossils show that Homo erectus hunted river turtles and large terrestrial animals.

The hunting techniques observed, such as targeting animals in their prime, are typically associated with more modern humans, raising questions about whether this H. erectus group developed such strategies independently or learned them through cultural exchange with other human relatives like Denisovans or Neanderthals. H. erectus is believed to have survived on Java until about 117,000 years ago, well after it disappeared elsewhere in Asia.