Arrange in sequence from the earliest to the most recent:
1. Australopithecus, Homo erectus, Homo habilis and Homo sapiens
2. Homo habilis, Homo sapiens, Australopithecus and Homo erectus
3. Homo habilis, Australopithecus, Homo sapiens and Homo erectus
4. Australopithecus, Homo habilis, Homo erectus and Homo sapiens