Testing the inhibitory cascade model in the Middle Pleistocene Sima de los Huesos (Sierra de Atapuerca, Spain) hominin sample.

Testing the inhibitory cascade model in the Middle Pleistocene Sima de los Huesos (Sierra de Atapuerca, Spain) hominin sample.
J Anat. 2020 Aug 24;:
Authors: Bermúdez de Castro JM, Modesto-Mata M, Martín-Francés L, García-Campos C, Martínez de Pinillos M, Martinón-Torres M
Abstract
The Middle Pleistocene Sima de los Huesos (SH) site has yielded more than 7.500 human fossil remains belonging to a minimum of 29 individuals. Most of these individuals preserve either the complete mandibular molar series or at least the first (M1 ) and second (M2 ) molars. The inhibitory cascade mathematical model was proposed by Kavanagh et al. (Nature, 449, 427-433 [2007]) after their experimental studies on the dental development of murine rodent species. The activator-inhibitor mechanism of this model has shown its ability for predicting evolutionary size patterns of mammalian teeth, including hominins. The main aim of this study is to test whether the size molar patterns observed in the SH hominins fit the inhibitory cascade model. With this purpose, we have measured the crown area of all SH molars in photographs, using a planimeter and following techniques used and well contrasted in previous works. Following one of the premises of the inhibitory cascade model, we expect that the central tooth (M2 in our case) of a triplet would have the average size of the two outer teeth. The absolute difference between the observed and the expected values f...

Source: Journal of Anatomy - August 23, 2020 Category: Anatomy Authors: Bermúdez de Castro JM, Modesto-Mata M, Martín-Francés L, García-Campos C, Martínez de Pinillos M, Martinón-Torres M Tags: J Anat Source Type: research