AMINO-ACID-COMPOSITION OF DINOSAUR EGGSHELLS NEARBY THE K T BOUNDARY IN NANXIONG BASIN, GUANGDONG PROVINCE, CHINA/

Amino acid analyses have been made of the fossil proteins from several samples of dinosaur eggshell, identified as Macroolithus yaotunensis, collected in the Upper Cretaceous Pingling Formation of the Nanxiong Basin, Guangdong Province, South China. The results indicate that the amino acid composition of the eggshells near the K/T boundary varies g reatly from specimen to specimen, and might reflect the different stat es of the original matrix protein when fossilization began. This findi ng and previously obtained evidence from analyses of trace elements, o xygen isotopes and the microstructure of the eggshells suggest that dr astic environmental changes adversely affected the reproductive proces s and contributed to the extinction of the dinosaurs.