Differences in tibial shape among the Prehispanic inhabitants from Gomera, Punta Azul (El Hierro), and Gran Canaria (Canary Islands).

The Canary Archipelago was colonized by North African Berbers who arrived at the Islands in the first millenium BC. Although it was classically considered that the prehispanic population was more or less uniform, recent genetic analysis has disclosed that some differences did exist between inhabitants of the different islands. From pure anthropometrical point of view, detailed inspection of some bones such as tibiae of prehispanic inhabitants of different islands allow the detection of some differences in tibial shape, especially regarding the relative size of both the proximal and distal thirds of these bones. On this basis, we have elaborated and calculated several indexes combining distal and proximal breadth measurements that define the global shape of the tibia. We have compared these indexes among the prehispanic population of the three islands for which sex has been accurately established. Both men and women from La Gomera, and, especially, from El Hierro, showed thicker distal ends of the tibiae with respect to proximal ones, in contrast with the population of Gran Canaria. In addition, differences among male and female tibiae were more marked among the population of Gran Canaria than among those of Gomera and El Hierro. Differences in these indexes could point either to differences in genetical background or to differences in activity. Compared with single anthropometric measurements, these indices separate better the population of the different islands. Just the opposite was observed when logistic regression analysis was used to analyse differences in sex.