Before I jet off to Pennsylvania, I wanted to comment again on the newly announced Au. sediba. I'm getting a lot of google traffic from people looking for a creationist response, and I didn't give a very satisfying one yesterday. So here's attempt #2 (there will be another attempt in the future).
Here's what you'll get from most creationists: "It's an ape." That might even satisfy many of you. In the long run, though, I think it's unsatisfactory. The problem is its head. Au. sediba has the most human-looking head of any australopith I've seen, even though the body looks very apish, with its really long arms. This has been a hallmark of creationist interpretation of australopiths: that they are mosaics of facultative bipeds (meaning they can walk around on two legs) and tree dwellers (indicated by long forearms). If I had only the (remarkable) skeletons to judge from, I'd probably say it was obviously an ape. But then there's that skull. When I first saw it, I thought it looked a lot like Homo habilis. Apparently, I'm not alone. Donald Johanson and Susan Antón are both quoted as preferring to place sediba within Homo.
What I want to do is use the same baraminology techniques I've always used to sort out relationships and clustering of taxa to figure out what Au. sediba is. As I've said here before, I have a hominid baraminology paper currently being edited, and I've requested that it be delayed until I can assimilate this new discovery, especially since it's one of such great significance. So my detailed response will have to wait until then.