Endocast of Sambungmacan 3 (Sm 3): A new Homo erectus from Indonesia

Abstract

A new fossil calvaria, Sambungmacan 3 (Sm 3), described in New Fossil Hominid Calvaria From Indonesia-Sambungmacan 3 by Márquez et al., this volume, yields one of the most advanced and complete endocasts yet recovered from Java. This communication provides a thorough interpretation of the external anatomical landmarks observable on Sm 3. Using computer tomography (CT) and traditional morphological measurements, our comparative paleoneurological analyses show that while Sm 3 has a mosaic of features that are similar to both Indonesian and Chinese H. erectus, it also possesses significant characters reminiscent of later hominins. These include a greater degree of asymmetry characterized by a possible left-occipital, right-frontal petalial pattern, left-right volumetric cerebral asymmetry, and marked asymmetry in Broca's cap. Moreover, the frontal lobe offers a more rounded, shortened appearance in contrast to the flat, elongated appearance of other Indonesian fossils (e.g., Sangiran 17). Another unique trait is exhibited in the transverse plane where the widest breadth of Sm 3 occurs more superiorly than in other Indonesian H. erectus. Thus, the endocast of Sm 3 presents a unique morphology not seen previously in the hominin fossil record. While the strong modern human characteristics in this endocast may not represent a particular ancestry, they do allow us to recognize a new dimension of the remarkable variation in Indonesian Homo erectus.

Paleoneurology of Two New Neandertal Occipitals from El Sidrón (Asturias, Spain) in the Context of Homo Endocranial Evolution

“…In the first case, the sample consists of scientific quality casts and virtual specimens, coming from CT data (Virtual Anthropology Collection, MNCN -CSIC-) and also from STL models (NESPOS, www.nespos.org). When necessary, literature has complemented and supported the observed data (Grimaud-Hervé, 1997;Broadfield et al, 2001;Holloway et al, 2004;Wu et al, 2006;Bruner and Manzi, 2008). H. sapiens data come from 64 dry skulls (Oloriz Collection, Department of Human Anatomy and Embryology I, UCM, Spain, http://www.ucm.…”

The Sambungmacan 3 Homo erectus calvaria: A comparative morphometric and morphological analysis

“…The comparative sample included 10 modern human crania from Tasmania and North China, as well as casts of 18 crania usually identified as Homo erectus (only 11 were used in the morphometric study) and two others often termed "archaic Homo sapiens" (see Table 1). Detailed morphological description of Sm 3 is provided by Má rquez et al (2001) while Broadfield et al (2001) discuss its paleoneurology. The major questions posed during this study were: 1.)…”

“…The morphology of the Sm 3 calvaria and its paleoneurology have been described respectively by Má rquez et al (2001) and Broadfield et al (2001), and here we undertake an analysis of its phylogenetic and systematic position using both three-dimensional (3D) geometric morphometric and comparative morphological analyses.…”

New high-resolution computed tomography data of the Taung partial cranium and endocast and their bearing on metopism and hominin brain evolution

“…and D.C.B. find no evidence for an open metopic suture, even ectocranially, in the Sambungmacan 3 Homo erectus cranium, having studied the original fossil and made endocast ourselves (30).…”