The relative ages of the rock strata deduced in this manner can be corroborated and at times refined by the examination of the fossil forms present.The tracing and matching of the fossil content of separate rock outcrops (i.e., correlation) eventually enabled investigators to integrate rock sequences in many areas of the world and construct a relative geologic time scale.Individual rocks in the myriad of rock outcroppings (or in some instances shallow subsurface occurrences) contain certain materials or mineralogic information that can provide insight as to their “age.”For years investigators determined the relative ages of sedimentary rock strata on the basis of their positions in an outcrop and their fossil content.
Sangiran 17 has been an important specimen for those who accept the multiregional hypothesis that has with gene flow being maintained between various African, Asian, and European populations.
The skullcaps are also characterized by flat, thick, rectangular parietal bones.
The facial bones are massive, and the mandibles are very robust.
No specimen from Indonesia has been found in a well-dated locale.
Often, they have been found by locals and bought by researchers or interested laypersons.