The shape of the internal acoustic porus of Sima de los Huesos: a comparative study

Amara Quirós-Sánchez, Ángeles Sánchez-Andrés, Julia Diez-Valero, José-Miguel Carretero, Ignacio Martínez, Mercedes Conde-Valverde

Supplementary material · ESHE 2026 – P019

Composition of the sample

Landmark protocol

The outline of the porus acusticus internus is delimited by five reference landmarks, defined geometrically on the perimeter itself. The four canal walls and their maximum measurement points follow Sakashita and Sando (1995).

Depth is controlled by orienting the model with the line of sight perpendicular to the aperture of the porus, so that the outline is seen edge-on and any point displaced into or out of the canal can be detected and corrected.

Distances between group mean shapes

Software and analysis

Segmentation and surface model export were performed in Mimics v.18 (Materialise, Leuven) and semilandmarks were digitised in Avizo 7.1. All statistical analyses were carried out in R 4.5.1 (R Core Team, 2025) with the geomorph package (v. 4.0.10; Baken et al., 2021; Adams et al., 2025). Procrustes ANOVA and pairwise comparisons were tested by residual randomisation (RRPP) with 9999 permutations, and p values were corrected by the Holm method

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