Figure 1
From: Cochlear shape distinguishes southern African early hominin taxa with unique auditory ecologies
Four new fossil hominins recovered from Kromdraai (South Africa) attributed to Paranthropus robustus, and mean cochlear shape in this species. The new specimens from Kromdraai represent three juvenile (KW 9600, KW 9700 and 10840) and one adult (KW 9990) individuals (blue circles). Blue squares represent other P. robustus specimens from Kromdraai, Swartkrans and Drimolen. Only SK 847 is attributed to early Homo (orange diamond). (A) Fréchet mean computed from our P. robustus sample (blue) aligned with the cochlear curve of the SK 847 early Homo specimen (orange) using exactly the same reference system and orientation. (B,C) Two distinct principal components analyses (PCA, with the variance percentages indicated for PC1 and PC2) using (B) one data set with the two angles and the seven indices listed in Table S3 (the variables that contribute most significantly to PC1 are, with decreasing loadings: TLI, HZL/ANL, ECL/POL, APA < LSCm and ECL/ANL); (C) the previous data set adding the incomplete bony labyrinth of KB 6067 (with its damaged anterior semi-circular canal) from Kromdraai27 and excluding the HZL/ANL, POL/ANL and ECL/ANL indices (the variables that contribute most significantly to PC1 are, with decreasing loadings: COs < LSCm and TLI).
