An organism's predecessors are the actual or imagined forms or stocks from which it has evolved or descended.
The oldest known member of the human lineage is called Ardipithecus, and it is thought to be the ancestor of the Australopithecus genus, which is closely linked to and frequently regarded as the ancestor of modern humans.
Between 5.8 million and 4.4 million years ago, Ardipithecus inhabited the Earth.