Mailbag: Denisovan diversity

I just watched the National Geographic documentary "Sex in the Stone Age" and was surprised by the reference to the discovery of a 2nd Denisovan tooth, one whose mitochondrial DNA was distinct enough from that of the MtDNA in the finger and original tooth to indicate that the Denisovan population had as much genetic diversity as H. Sapiens currently has today. This is interesting, since if I recall correctly, Neanderthals had low levels of genetic diversity, with evidence of replacement of their western European population by an Eastern population. This perhaps indicates that the Denisoans had a larger population than that of the Neanderthals. I don't recall reading about this find on your website or anywhere else. I'm not a scientist, just a history/english teacher who's extremely interested in human evolution and I try very hard to stay on top of these things. Did I miss an important paper or something?

The second tooth has not yet been published. The mtDNA was sequenced and is distinct from the first two sequences by a substantial degree. The nuclear DNA has not been sequenced. The original finger bone has given rise to a much higher quality sequence that will be published in the next few weeks. This will give a better idea of the size and diversity of the population when it comes out.