Advances in the application of compound-specific isotope analysis of amino acids in archaeological research

Stable isotope bioarchaeology is an important area of bioarchaeological research, which can provide direct evidence for reconstructing the trophic positions and dietary sources of ancient humans and animals. Compared with bulk bone collagen isotope analysis, compound-specific isotope analysis of amino acids (CSIA-AA) can effectively overcome the inherent limitations of the traditional method in terms of isotopic baseline variation, fertilization effects, and physiological stress, ensuring more precise determination of the trophic positions and food resource utilization of ancient humans and animals. This method has become a research frontier in international bioarchaeology, but its application remains underdeveloped in China. To address this gap, we introduced the fundamental concepts and analytical principles of CSIA-AA, illustrated its unique advantages in paleodietary reconstruction through representative case studies, and reviewed advances in areas such as the optimization of trophic position estimation parameters, machine learning assisted dietary discrimination, and the reconstruction of individual life histories. Finally, we provided a prospective outlook on the application of CSIA-AA in archaeological research in China.