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Updated: Jul 11, 2026
08:15
Reverse Dissection and DiceCT Reveal Otherwise Hidden Data in the Evolution of the Primate Face
Published on: January 7, 2019
Homo erectus calvarium from the Pleistocene of Java
Hisao Baba1, Fachroel Aziz, Yousuke Kaifu
1Department of Anthropology, National Science Museum, Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan. baba@kahaku.go.jp
Science (New York, N.Y.)
|March 1, 2003
Summary
The Homo erectus Sambungmacan 4 fossil shows modern human-like cranial base flexion, suggesting cranial globularity evolved independently. This finding supports limited Javanese Homo erectus contribution to modern human ancestry.
Area of Science:
- Paleoanthropology
- Human Evolution
- Paleontology
Background:
- The evolutionary history of Homo erectus provides insights into human origins.
- Understanding cranial morphology changes is key to tracing human lineage.
- The Javanese Homo erectus fossil record offers a unique window into later stages of H. erectus evolution.
Purpose of the Study:
- To analyze the cranial morphology of the Sambungmacan 4 (Sm 4) Homo erectus calvarium.
- To investigate the relationship between cranial base flexion and cranial vault shape in Homo erectus.
- To assess the phylogenetic position of Sm 4 within the Homo erectus lineage and its contribution to modern human ancestry.
Main Methods:
- Recovery of the Homo erectus calvarium (Sm 4) from Pleistocene sediments.
- Micro-computed tomography (CT) analysis of the Sm 4 calvarium.
- Comparative morphological analysis with other Homo erectus fossils and modern humans.
Main Results:
- The Sm 4 calvarium exhibits modern human-like cranial base flexion.
- A low platycephalic (flat) vault was observed in conjunction with cranial base flexion.
- The morphology of Sm 4 is intermediate between earlier and later Javanese Homo erectus, with later specimens showing more specialized features.
Conclusions:
- Cranial globularity in human evolution likely evolved independently of cranial base flexion.
- The morphological distinctiveness of later Javanese Homo erectus suggests population isolation.
- Later Pleistocene Javanese Homo erectus populations contributed minimally to the ancestry of modern humans.
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