COMPARATIVE ANATOMY ANALYSIS FOR DETERMINING HUMAN EVOLUTION BASED ON HUMAN FOSSILS FROM NGANDONG, EAST JAVA

Abstract

The human fossil which is known as Ngandong fossils was discovered by von Koenigswald in the 1930's. At the beginning of the discovery, the Ngandong fossil was not as an attractive object to be studied by paleoanthropologist. But from the beginning of the 90's, there was a controversy surrounding the existence of Ngandong fossil as the "missing link" in the history of human evolution kept sticking to invite many researchers from around the world to examine this fossil. Based on this background, purpose of this study is to confirm the position of the Ngandong fossil in the human evolution tree based on biometric data and morphological observation of the fossil skull (cranium) of the Ngandong fossil. Measurement data of Ngandong fossil specimens compared with the fossil skulls from Sangiran and Africa and the modern human skulls as well to answer the question : Is the "Late Homo erectus" comparable with the "Early Homo sapiens?" Ngandong fossil specimens which are used in this study are the replicas of the skulls of Ngandong 9, 10 and 11 (Ng 9, Ng 10 and Ng 11). All these specimens are the cast of original fossil found in Ngandong East Java, consist of frontal, temporal, parietal and occipital bone. For the comparison, in this study was used the replicas of the fossils from Sangiran (Sn17), Wajak (Wajak1) and Africa (Lh18) which consists of the frontal, parietal and occipital, as well as an original modern human skull (M), which was estimated as juvenile, including full face and maxilla. Analytical methods which used are qualitative including descriptions, comparative anatomy, and quantitative method such as biometrical measurement and statistics. Before the measurements were performed, the most important step is to identify each parameter, especially the ‘sutures’. To get the best results, biometrical measurements performed in three times on each specimen. The statistical analysis then performed by the method of PCA (Principal Component Analysis). Comparative anatomy of all samples shows a development in size and shape between all samples. The sequence development of cranium shape and size based on parameters that contribute most to PC1, PC2, and PC3 from PCA those are maximum cranial length, biauricular breadth, occipital chord, and parietal chord. Changes in size of the skull (cranium) is affected by changes in shape, the shape change is likely influenced by expansion of the brain which increases in size by increasing of nutrition absorption. The development of cranial shape anatomically is increasing in height of temporal bone (heightening)and parietal bone so the form of cranium be more rounded.. If we assume that the development of the shape and size from the more primitive to the advanced is the group of Lh18 (Homo habilis) and Sn17 (Homo erectus archaic/Early Homo erectus), developed into Ng9, Ng11, and Ng10 (Homo erectus progressive/Late Homo erectus). Later, those group evolved into Wajak1(Homo sapiens) and latest evolved by time and space into M which is modern human. In other word, Homo erectus progressive/Late Homo erectus is the ancestor of Homo sapiens so terminology Late Homo erectus can be aligned with Early Homo sapiens.