Scientist regard Homo erectus as the first true species of human. There are many theories of the mother of this species. Some believe they evolved from Australopithecus, Savannah ape, aquatic ape, and others. Similarly, their habitat was equally diverse. Remains were found from Java (Pithecanthropus) by Dubois, another out of China (Sinanthropus Pekinensis), and the oldest Olduvai Gorge (estimated 750,000 years old).