Ancient DNA: Prospects and limitations

Abstract

Ancient DNAs hold tremendous potential for studies of phylogeny, biogeography, and molecular evolution. In this paper we review published reports of DNA extracted from preserved plant and animal tissues. These preserved materials range in age from a 120 year old museum specimen of the extinct marsupial wolf to Oligocene-Miocene (25-30 million year old) termites and stingless bees preserved in amber. The mode of perservation of the tissue, molecular analysis, and biological significance, if any, of each study are discussed. In addition, we present our assessment of the future prospects of molecular paleontology. Finally, the principal limitations of fossil DNA extraction and characterisation are discussed, including degradation and modification of ancient DNA, difficulties in amplification of target sequences via the polymerase chain reaction, and the special problems that contamination presents for amplification and verification of fossil DNA sequences. © 1993 Taylor & Francis Group, LLC.