Some see rudolfensis as the ancestor of habilis with a decrease in brain size occurring, and others see the two on completely different evolutionary lines.
The genus name of Pithecanthropus has been dropped by those who
see rudolfensis as a valid species and replaced with the genus Homo.
As stated, the attribution of the species rudolfensis to any specimen is somewheat controversial, since many paleoanthropologists do not
see rudolfensis as a valid species.