Another little piece of information indicating that there are substantial differences between the two big-headed Homo species.
Tanya M. Smit et al., Dental evidence for ontogenetic differences between modern humans and Neanderthals. PNAS 2010. Open access.
Armed with state-of-the-art tomographic scanners, this paleontological team was determined to settle what previous research had only found inconclusive: whether Neanderthal development was faster paced or similar to that of Homo sapiens.
The results seem quite clear:
|Fig. 3 (Predicted ages are derived from human radiographic
Neanderthals, but not ancient H. sapiens, clearly deviate from the developmental pattern of our species, with teeth (and hence most likely all them) developing faster than among us.
It seems from this data that a 12 y.o. Neanderthal would be as developed as a 16 y.o. modern human. One can easily infer that they should reach puberty some 2-3 years earlier than we do, though this is not directly in the teeth and also shows some notable variability among modern humans.