Biological Relationships across the Taiwan Strait: Evidence from Skulls and Teeth

Abstract

The initial Neolithic on the island of Taiwan represents the earliest known littoral and pelagic resource exploiting groups outside of the East Asian mainland. The objective of this dissertation is to perform a cross-Taiwan Strait analysis of biological distance, or biodistance, of those archaeological cultures thought to have been involved in the introduction of this new lifeway and culture to Taiwan. Biological distance is a statistical measure of observable phenotypic relationships that can be equated to estimated genetic relationships by using a model-bound R-matrix approach. Biological distance measures can therefore be used to determine biological affinity across the Taiwan Strait at the introduction of the Neolithic and identify changes in those relationships through time. The coastal and deep sea exploiting Neolithic of the Southeast coast of China and the Taiwan Strait is thought to have been introduced or invented by 7,000 years ago and introduced to the island of Taiwan by 5,000-4,500 years ago. Data were collected on a suite of cranial and dental metrics from five archaeological cultures from both sides of the Taiwan Strait dating to this time period. These data, combined with local, regional, and Asia-Pacific data from the literature, were subjected to local, regional and inter-regional statistical analyses. The results of the cross-Taiwan Strait analysis indicated that cross-strait relationships at the time of the initial Neolithic on Taiwan are weak. Cross-strait gene flow became more restricted through time. The late prehistoric and modern Indigenous Taiwanese are characterized by isolation and endogamy. Regional analyses of biodistance, when compared to Neolithic China samples, find the Taiwan Strait as a region is distinct from the Neolithic populations of the central valleys of the Yellow and Yangtze Rivers and from the Yangtze River delta area. The relationships with these Neolithic groups suggest the inhabitants of the Neolithic Taiwan Strait are not part of the larger genetic exchange of the central river valleys. Inter-regional comparisons with Asia-Pacific cranial samples suggest the Taiwan Strait area is at the root of the division between East Asian and Island Southeast Asian populations. The relationship with Island Southeast Asia lasts through time.