Members of the Knoll lab are broadly interested in the evolution of life, the evolution of Earth surface environments, and the relationships between the two. We are particularly interested in Archean and Proterozoic paleontology and biogeochemistry; however, both past and current projects include investigations of selected problems in Phanerozoic Earth history. Motivating evolutionary issues include the diversification of prokaryotic metabolisms on the Precambrian Earth, the initial radiation of eukaryotic life, and the rise of large complex algae and animals near the end of the Proterozoic Eon. Current projects that address these issues include coupled paleontological/biogeochemical work on late Archean basins from southern Africa and Australia, mid-Proterozoic basins in Australia, and Neoproterozoic-Cambrian successions in northern Russia and Australia. In a genuine extension of this research, we are also involved actively in Mars exploration, both as part of the 2004 MER missions and in planning for future landings. In other work, our lab is engaged in studies of Triassic recovery from end-Permian mass extinction and, more broadly, in an effort to apply physiological insights to problems of Paleozoic biological and environmental evolution. Specific research in the latter area includes combined microchemical/anatomical analyses designed to provide quantitative estimates of whole plant physiological performance in extinct vascular plants.

Selected Publications:

Knoll, A.H. (1992) The early evolution of eukaryotic organisms: a geological perspective. Science 256: 622-627.

Kaufman, A.J. and A.H. Knoll (1995) Neoproterozoic variations in the carbon isotopic composition of seawater: stratigraphic and biogeochemical implications. Precambrian Research 73: 27-49.

Knoll, A.H., R. Bambach, D. Canfield, and J.P. Grotzinger (1996) Comparative Earth history and late Permian mass extinction. Science 273: 452-457.

Xiao, S., Y. Zhang, and A.H. Knoll (1998) Three-dimensional preservation of algae and animal embryos in a Neoproterozoic phosphorite. Nature 391: 553-558.

Grotzinger, J.P., and A.H. Knoll (1999) Proterozoic stromatolites: evolutionary mileposts or environmental dipsticks? Annual Review of Earth and Planetary Science 27: 313-358.

Knoll, A.H. and S.B. Carroll (1999) The early evolution of animals: Emerging views from comparative biology and geology. Science 284: 2129-2137.

Javaux, E., A.H. Knoll, and M.R. Walter (2001) Ecological and morphological complexity in early eukaryotic ecosystems. Nature 412: 66-69.

Boyce, C.K. and A.H. Knoll (2002) Evolution of developmental potential and the multiple independent origins of leaves in Paleozoic vascular plants. Paleobiology 28: 70-100.

Anbar, A.D. and A.H. Knoll (2002) Proterozoic ocean chemistry and evolution: a bioinorganic bridge? Science 297: 1137-1142.

Knoll, A.H. (2003) The geological consequences of evolution. Geobiology 1: 3-14.

Shen, Y., A.H. Knoll, and M.R. Walter (2003) Evidence for low sulphate and deep water anoxia in a mid-Proterozoic marine basin. Nature 423: 632-635.

Knoll, A.H. (2003) Life on a Young Planet: The First Three Billion Years of Evolution on Earth. Princeton University Press, Princeton, New Jersey.

Payne, J., D. Lehrmann, J. Wei, M.J. Orchard, D.P. Schrag, and A.H. Knoll (2004) Large perturbations of the carbon cycle during recovery from the end-Permian extinction. Science 305: 506-509.

Squyres, S. and others (2004) In-situ evidence for an ancient aqueous environment on Mars. Science 306: 1709-1714.