Nope. We're all human. There is only one species of humans and all this Homo-this and Homo-that is hog wash.
All of the features of (so-called) 'extinct humans' can be found in humans today all over the world. If you put all the uniqueness of any combination of these 'traits' together (obtained from modern humans today) you can come up with any Homo-? you desire. It's called "The Multi-regional Theory'. The idea is covered thoroughly in Professor Milford Wolpoff's new book titled: Race And Human Evolution.
There has only ever been one human.
Agreed that homo erectus WAS human, along with Neanderthals. Still, those humans remains which are today labeled as homo erectus could have been branches of humanity which died out. Also, physiological appearance is not necessarily indicative of direct descent.
oh ok.
But I still doubt it a bit. I do think it very likely that many species are really one and the same, but according to a paleantologist professort the differences between, for instance, neanderthals and humans at that time are far bigger then the difference between any two modern day humans.
I don't know how large the differences are between Homo XX
species, but if neanderthals where a different species, than I think it possible that more humanoids have diverged sufficinetly to become a separate species.