text: In the early Pleistocene , 1.5 â `` 1 Ma , in Africa , Asia , and Europe , some populations of Homo habilis are thought to have evolved larger brains and made more elaborate stone tools ; these differences and others are sufficient for anthropologists to classify them as a new species , Homo erectus .
simplified: In the Early Pleistocene , 1.5 â `` 1 mya , in Africa , Asia , and Europe , presumably , some populations of Homo habilis evolved larger brains and made more elaborate stone tools ; these differences and others are sufficient for anthropologists to classify them as a new species , H. erectus .