Article: Amino acids from fossils, facies and fingers

The possibility of introducing contaminating amino acids while preparing fossils and rocks analysis is a major problem for molecular palaeontology. The most important source of contamination is human finger tips, which source approximately 100 times the concentration of amino acid than New Zealand fossil shells. Latex gloves can also transmit appreciable quantities of modern day amino acids. However hierarchical clustering and principal component analysis reveal that the relative proportions of finger-tip amino acids are constant to an extent which allows them to be readily distinguished from those for fossil shells and their enclosing sediment. This approach therefore represents a useful method of checking for contamination by finger tips in analyses of fossil molecules.