Crown-formation time in Neandertal anterior teeth revisited.

Our knowledge on the growth of anterior teeth in extant and extinct humans has recently been broadened. Two studies have compared Neandertal dental growth with that of Upper PaleolithiceMesolithic humans and with modern contemporary humans. Neandertals clearly show fewer perikymata in their anterior teeth than do Upper PaleolithiceMesolithic people of Europe, as reported by Ramı́rez Rozzi and Bermúdez de Castro (2004). However, when modern human populations are compared with a sample of Neandertal teeth used by Guatelli-Steinberg et al. (2005), the number of perikymata in this extinct human group is encompassed within the modern human range of variation. Using histological sections of anterior teeth, Guatelli-Steinberg et al. (2005, 2007a,b) obtained the total number of perikymata in two modern human populations (Newcastle and South Africa). However, faced with the impossibility of sectioning fossil teeth, they followed a different methodology to determine the total number of perikymata in their sample of Neandertal anterior teeth. Here we present some observations about the methods Guatelli-Steinberg et al. used to analyze their sample of Neandertal teeth and show that their results are inaccurate and thus cannot be used as comparative data in future studies.