Svante Pääbo, a leading pioneer in the study of ancient DNA, eloquently described the recovery of genetic information from the fossil record as a 21st Century form of genetic time travel1. The advent of PCR made possible the amplification of small amounts of DNA from fossil samples and allowed the direct study of phylogenetics from extinct organisms. Prior to this development, phylogenetic relationships determined by genetic variation relied mostly upon sequences from living organisms. The concept of time travel, via the analysis of ancient biomolecules, can be broadened to encompass numerous types of biomolecular information recovered from ancient bones. For example, palaeodiets and palaeoclimates can be reconstructed from stable isotopes of bone collagen, and estimations of age are obtained from amino acid racemization rates.
Detection of Localized Hepatocellular Amino Acid Kinetics by using Mass Spectrometry Imaging of Stable Isotopes