Reply #5: Seriously? [View All]

You basically take a list of features that distinguish humans from apes. If a specimen or group of specimens has a lot of human characteristics, call it a hominid. Then you spend twenty years arguing about it, all the while new data are coming in.

There are cases of hominids that aren't ancestral, for example among the Austrolopithecenes. To find the ancestors, you basically do the same thing in that group and weed out the ones with unusual features, like robustus. The reasoning is that once a successful adaptation takes place, it's not likely to revert to a more primordial state and start again. So you can't say with absolute certainty that A. robustus is not an ancestor, but it would be extremely unlikely. A. afarensis, on the other hand, is almost certainly an ancestor.

Here's a chart: http://www.archaeologyinfo.com/species.htm

In the case of ramidus, we see features associated with an adaptation for bipedalism. The position of the foramen magnum was mentioned in the Times article. There's also the phalanx that was unearthed. There is also a femur, which has a large balled head suggestive of bipedalism. Taken together it's pretty strong evidence of both a divergence from the line leading to modern Chimps, and the begining of the line leading to Homo sapiens.