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Nettersheim BJ, Brocks JJ, Schwelm A, Hope JM, Not F, Lomas M, Schmidt C, Schiebel R, Nowack ECM, DeDeckker P, Pawlowski J, Bowser SS, Bobrovskiy I, Zonneveld K, Kucera M, Stuhr M, Hallmann C (2019) Putative sponge biomarkers in unicellular Rhizaria question an early rise of animals. Nature Ecology & Evolution 3: 577–581.

van Maldegem LM, Sansjofre P, Weijers JWH, Wolkenstein K, Strother PK, Wörmer L, Hefter J, Nettersheim BJ, Hoshino Y, Schouten S, Sinninghe Damsté JS, Nath N, Griesinger C, Kuznetsov NB, Elie M, Elvert M, Tegelaar E, Gleixner G, Hallmann C (2019) Bisnorgammacerane traces predatory pressure and the persistent rise of algal ecosystems after Snowball Earth. Nature Communications 10: 476.

Leider A, Richter-Brockman S, Nettersheim BJ, Achten C, Hallmann C (2019) Low femtogram sensitivity analysis of polyaromatic hydrocarbons using GC-APLI-TOF mass spectrometry: extending the target window for aromatic steroids in early Proterozoic rocks. Organic Geochemistry 129: 77–87.

Illing CJ, Hallmann C, Scott AC, Collinson M, Briggs DEG, Strauss H, Summons RE (2019) Heterogeneity of free and occluded bitumen in a natural maturity sequence from Oligocene Lake Enspel. Geochimica et Cosmochimica Acta 245: 240–265. 

Luo G, Yang H, Algeo TJ, Hallmann C, Xie S (2019) Lipid biomarkers for the reconstruction of deep-time environmental conditions. Earth Science Reviews 189: 99–124.

Servais T, Cascales-Minana B, Cleal C, Harper D, Neumann M, Gerrienne P (2019) Revisiting the great Ordovician diversification of land plants: recent data and perspectives. Palaeogeography, Palaeoclimatology, Palaeoecology 534: 109280

Hallmann C, Nettersheim BJ, Brocks JJ, Schwelm A, Hope JM, Not F, Lomas M, Schmidt C, Schiebel R, Nowack ECM, DeDeckker P, Pawlowski J, Bowser SS, Bobrovskiy I, Zonneveld K, Kucera M, Stuhr M (in press) Reply to: Sources of C30 steroid biomarkers in Neoproterozoic–Cambrian rocks and oils. Nature Ecology & Evolution.

Schmidt C, Nikeleit V, Schaedler F, Leider A, Leder U, Bryce C, Hallmann C, Kappler A (in review) Metabolic flexibility in a photoferrotrophic co-culture enriched from a freshwater sediment and its relevance for biogeochemical iron cycling. 



Bobrovkiy I, Hope J, Ivantsov A, Nettersheim BJ, Hallmann C, Brocks JJ (2018) Ancient steroids establish the Ediacaran fossil Dickinsonia as one of the earliest animals. Science 361: 1246–1249.

Botting JP, Nettersheim BJ (2018) Searching for sponge origins. Nature Ecology & Evolution 2: 1685–1686.

Peters CA, Hallmann C, George SC (2018) Phenolic compounds in oil-bearing fluid inclusions: implications for water-washing and oil migration. Organic Geochemistry 118: 36–46.

Muller E, Thomazo C, Stüeken, E, Hallmann C, Leider A, Chaduteau C, Buick R, Baton F, Ader M (2018) Bias in carbon concentration and δ13C measurements of organic matter due to cleaning treatments with organic solvents. Chemical Geology 493: 405–412.


Hoshino Y, Poshibaeva A, ..., Hallmann C (2017) Cryogenian evolution of stigmasteroid biosynthesis. Science Advances 3: e1700887. DOI: 10.1126/sciadv.1700887

Brocks JJ, Jarret AM, Sirantoine E, Hallmann C, Hoshino Y, Liyanage T (2017) The rise of algae in Cryogenian oceans and the emergence of animals. Nature 548: 578–582. DOI: 10.1038/nature23457


Leider A, Schumacher T, Hallmann C (2016) Enhanced procedural blank control for organic geochemical studies of critical sample material. Geobiology 14: 469–482. DOI: 10.1111/gbi.12183

Ferralis N, Matys E, Knoll AH, Hallmann C, Summons RE (2016) Rapid, direct and non-destructive assessment of fossil organic matter via microRaman spectroscopy. Carbon 108: 440–449. DOI: 10.1016/j.carbon.2016.07.039


Williford KH, Ushikubo T, Lepot K, Kitajima K, Hallmann C, Spicuzza MJ, Kozdon R, Eigenbrode JL, Summons RE, Valley JW (2015) Carbon and sulfur isotopic signatures of ancient life and environment at the microbial scale: Neoarchean shales and carbonates. Geobiology. DOI: 10.1111/gbi.12163 

Feulner G, Hallmann C, Kienert H (2015) Snowball cooling after algal rise. Nature Geoscience 8: 659–662. DOI: 10.1038/ngeo2523 Also see editorial.

Huang Y, Aponte JC, Zhao J, Tarozo R, Hallmann C (2015) Hydrogen and carbon isotopic ratios of polycyclic aromatic compounds in two CM2 carbonaceous chondrites and implications for prebiotic organic synthesis. Earth and Planetary Science Letters 426: 101–108. DOI: 10.1016/j.epsl.2015.06.027

French K, Hallmann C, Hope J, Schoon PL, Zumberge JA, Hoshino Y, Peters CA, George SC, Love GD, Brocks JJ, Buick R, Summons RE (2015) Reappraisal of hydrocarbon biomarkers in Archean rocks. Proceedings of the National Academy of Sciences USA 112: 5915–5920. DOI: 10.1073/pnas.1419563112

Hallmann C (2015) Von Bakterien zum Menschen: Die Rekonstruktion der frühen Evolution mit fossilen Biomarkern [From bacteria to humans: reconstructing early evolution with fossil biomarkers]. In: Max Planck Jahrbuch 2014 / 2015. Link.

Luo G, Hallmann C, Summons RE, Xie S, Ruan X (2015) Microbial diversity and redox environments of black shale and stromatolite facies in the Mesoproterozoic Xiamaling Formation, North China Craton. Geochimica et Cosmochimica Acta 151: 150–167. DOI: 10.1016/j.gca.2014.12.022


Illing CJ, Hallmann C, Miller, K.E., Strauss H, Summons RE (2014) Air-borne hydrocarbon contamination from laboratory atmospheres. Organic Geochemistry 76: 26–38. DOI: 10.1016/j.orggeochem.2014.07.006

Aponte JC, Tarozo R, Alexander MR, Alexander CM, Charnley SB, Hallmann C, Summons RE, Huang Y (2014) Chirality of meteoritic free and IOM-derived monocarboxylic acids and implications for prebiotic organic synthesis. Geochimica et Cosmochimica Acta 131: 1–12. DOI: 10.1016/j.gca.2014.01.035

Rooney AD, Macdonald FA, Dudas FÖ, Strauss JV, Hallmann C, Selby D (2014) Re-Os geochronology and coupled Os-Sr isotope constraints on the Sturtian snowball Earth. Proceedings of the National Academy of Sciences USA 111: 51–56. DOI: 10.1073/pnas.1317266110

Hallmann C, Summons RE (2014) Paleobiological clues to early atmospheric evolution. In: Canfield D, Kasting J, Farquhar J (Eds) Treatise on geochemistry 2nd Ed., Vol. 6: The atmosphere – History Elsevier. pp 139–155. DOI: 10.1016/B978-0-08-095975-7.01305-X

Summons RE, Hallmann C (2014) Organic geochemical signatures of early life on earth. In: Falkowski P, Freeman K (Eds) Treatise on geochemistry 2nd Ed., Vol. 12: Organic Geochemistry. Elsevier. pp 33–46. DOI: 10.1016/B978-0-08-095975-7.01005-6


Creveling JC, Knoll AH, Fernandez-Remolar D, Bergmann KD, Gill BC, Garcia-Bellido DC, Menendez S, Rodriguez M, Ehlmann BL, Stack KM, Hallmann C, Amils R, Grotzinger JP, Abelson J (2013) Geobiology of a lower Cambrian carbonate platform, Pedroche Formation, Spain. Paleogeography, Paleoclimatology, Paleoecology 386: 459–478. DOI: 10.1016/j.palaeo.2013.06.015

Sherry A, Gray ND, Rowan AK, Aitken CM, Jones DM, Röling W, Hallmann C, Larter SR, Bowler B, Head I (2013) Biodegradation of crude oil under sulfate-reducing conditions leads to only modest enrichment of recognized sulfate-reducing taxa. International Biodeterioration and Biodegradation 81, 105–113. DOI: 10.1016/j.ibiod.2012.04.009


Hallmann C, Kelly AE, Gupta SN, Summons, RE (2011) Reconstructing deep-time biology with molecular fossils. In: Laflamme M, Schiffbauer JD, Dornbos SQ (Eds) Topics in Geobiology, Vol 36: Quantifying the evolution of early life. Springer. pp 355–401. DOI: 10.1007/978-94-007-0680-4_14

Hallmann C, Grey K, Webster LJ, McKirdy DM, Grice K (2010) Molecular signature of the Neoproterozoic Acraman impact event. Organic Geochemistry 41, 111–115. DOI: 10.1016/j.orggeochem.2009.11.007

Grice K, Lu H, Atahan P, Asif M, Hallmann C, Greenwood P, Maslen E, Tulipani S, Williford K, Dodson J (2009) New insights into the origin of perylene in geological samples. Geochimica et Cosmochimica Acta 73, 6531–6543. DOI: 10.1016/j.gca.2009.07.029

Maslen E, Grice K, Gale JD, Hallmann C, Horsfield B (2009) Crocetane: a potential marker of photic zone euxinia in thermally mature sediments and crude oils of Devonian age. Organic Geochemistry 40, 1–11. DOI: 10.1016/j.orggeochem.2008.10.005

Hallmann C, Schwark L, Grice K (2008) Community dynamics of anaerobic bacteria in deep petroleum reservoirs. Nature Geoscience 1, 588–591. DOI: 10.1038/ngeo260

Hallmann C, van Aarssen BGK, Grice K (2008) Relative efficiency of free fatty acid butyl esterification. Choice of catalyst and derivatization procedure. Journal of Chromatography A 1198–1199, 14–20. DOI: 10.1016/j.chroma.2008.05.030

Hallmann C*, Arouri KR, McKirdy DM, Schwark L (2007) Temporal resolution of an oil charging history—A case study of residual oil benzocarbazoles from the Gidgealpa Field. Organic Geochemistry 38, 1516–1536. DOI: 10.1016/j.orggeochem.2007.05.006

Hallmann C*, Arouri KR, McKirdy DM, Schwark L (2006) A new perspective on exploring the Cooper/Eromanga petroleum province—Evidence of oil charging from the Warburton basin. APPEA Journal 46, 261–282. DOI: