Ancient biomolecules in Quaternary palaeoecology
Authors: Hofreiter, M., Collins, M. and Stewart, J.R.
Journal: Quaternary Science Reviews
The last few years have seen an enormous proliferation of ancient biomolecules research, especially in ancient DNA. DNA studies have been transformed by the advent of next generation sequencing, with the first Pleistocene sample being analysed in 2005, and by now allowing complete genomes to be compiled from ancient DNA. At the same time, although less conspicuous, research on ancient proteins has also seen major advances, with the time limit for research on ancient biomolecules extending to 1 million years and more. Here we review which effects these developments have on research in Quaternary sciences. We identify several lines of research that have the potential to profit substantially from these recent developments in ancient biomolecules research. First, the identification of taxa can be made using ancient biomolecules, and in the case of aDNA, specimens can even be assigned to specific populations within a species. Second, increasingly large DNA data sets from Pleistocene animals allow elucidating ever more precise pictures of the population dynamic processes whereby organisms respond to climate and environmental change. With the accompanying better understanding of process in the Quaternary, past ecologies can also be more realistically be interpreted from proxy data sets. The dominant message from this research so far is that the Quaternary saw a great deal more dynamism in populations than had been forecast by conventional palaeoecology. This suggests that reconstructions of the past environmental conditions need to be done with caution. Ancient DNA can also now be obtained directly from sediments to elucidate the presence of both plant and animal species in an area even in the absence of identifiable fossils (be it macro- or micro-fossils). Furthermore, the analysis of proteins enables the identification of bone remains to genus and sometimes species level far beyond the survival time of DNA, at least in temperate regions illustrating that precise data is now forthcoming from seemingly unlikely sources. Together, these approaches allow the study of environmental dynamics throughout a substantial part, and perhaps even the entire Quaternary (the last 2.6 million years).
Preferred by: John Stewart