Paleoneurology of the Proboscidea (Mammalia, Afrotheria): Insights from Their Brain Endocast and Labyrinth

2006) to twenty species (Table 15.1; the classification and phylogeny of fossil species follows Sanders et al. [...] This value is close to that reconstructed for the last common ancestor of the Mammutida by Benoit et al. [...] This illustrates that the evolution of encephalization in proboscideans is strongly tied to phylogeny, even compared to the effect of body mass (Benoit et al. 2019). [...] The other major clade of the Elephantimorpha is the Elephantoidea (Fig. 15.2). Benoit et al. [...] falconeri), which implies that a large brain would have co-evolved with large body size since the Paleogene in proboscideans. This is only partly supported by the study of Benoit et al. [...] The dorsal surface of the hemispheres is however slightly more rounded and protruding dorsally in Moeritherium than in other Paleogene paenungulates (Benoit et al. 2013b) (Fig. [...] The brain cavity is described as globular and two times smaller than the rostrum of the skull (~50 mm in length) (Gheerbrant et al. 2005). [...] The cerebellum of extant elephants is proportionately and absolutely the largest of all mammals examined to date (Maseko et al. 2012). [...] This strongly suggests that a mobile and prehensile upper lip was already present in the basal-most proboscideans and is likely a plesiomorphic feature of the Tethytheria (Gheerbrant et al. 2005) (Fig. 15.5). [...] The Sirenia, which are the closest living relatives of elephants (Poulakakis and Stamatakis 2010; Kuntner et al.