I also do not think that there is enough solid evidence to make a theory about the origin of the species. Particularly in light of recent findings in genetic studies.

It is a problematic finding because of our current understanding of early >fossils, such as the famous Toumai specimen uncovered in Chad.

Toumai (Sahelanthropus tchadensis) was thought to be right at the foot of the human family tree. It dates to between 6.5 and 7.4 million years ago. In other words, it is older than the point of human-chimp divergence seen in the genetic data.

One of the other problems is that our predecessors fooled around with other branches of hominids:

http://www.physorg.com/news/2011-10-genes-neanderthal-relatives-unusual.html