Coleoptera and microbe biomass in Antarctic Dry Valley paleosols adjacent to the Inland Ice: Implications for Mars William C. Mahaney a,n , Kris M. Hart b , Shane S. O’Reilly b , Christopher C.R. Allen c , James M. Dohm d , Ronald G.V. Hancock e , Brian P. Kelleher b , Michael W. Milner f a Quaternary Surveys, 26 Thornhill Ave., Thornhill, Ontario, Canada L4J 1J4 b School of Chemical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland c The School of Biological Sciences, Queen’s University Belfast, Medical Biology Centre, Lisburn Road, Belfast BT9 5AG, N. Ireland, UK d Department of Hydrology and Water Resources, University of Arizona, Tucson, AZ 85721, USA e Medical Physics and Applied Radiation Sciences, and Department of Anthropology, McMaster University Hamilton, Ontario, Canada L8S 4K1 f MWM Consulting, 182 Gough Ave., Toronto, Ontario, Canada M4K 3P1 article info Article history: Received 28 October 2011 Received in revised form 11 November 2011 Accepted 12 November 2011 Available online 29 November 2011 Keywords: Paleosols in the Dry Valleys Antarctica and on Mars SEM analysis of Coleoptera in Dry Valley paleosols Bacteriology of Antarctic paleosols abstract Bulk paleosol samples collected from a Middle to Early Miocene moraine in the New Mountain area of the Dry Valleys, Antarctica, yielded Coleoptera exoskeletons and occasional endoskeletons showing considerable diagenetic effects along with several species of bacteria, all lodged in a dry-frozen but salt- rich horizon at shallow depth to the land surface. The till is at the older end of a chronologic sequence of glacial deposits, thought to have been deposited before the transition from wet-based to cold-based ice ( 15 Ma), and hence, entirely weathered in contact with the subaerial atmosphere. It is possible, though not absolutely verifiable, that the skeletons date from this early stage of emplacement having undergone modifications whenever light snowmelt occurred or salt concentrations lowered the freezing temperature to maintain water as liquid. Correlation of the Coleoptera species with cultured bacteria in the sample and the likelihood of co-habitation with Beauveria bassiani found in two adjacent, although younger paleosols, leads to new questions about the antiquity of the Coleoptera and the source of N and glucose from chitinase derived from the insects. The skeletons in the 831 section may date close to the oldest preserved chitin (Oligocene) yet found on Earth. While harsh Martian conditions make it seemingly intolerable for complex, multicellular organisms such as insects to exist in the near- surface and subaerially, life within similar cold, dry paleosol microenvironments (Cryosols) of Antarctica point to life potential for the Red Planet, especially when considering the relatively diverse microbe (bacteria and fungi) population. & 2011 Elsevier Ltd. All rights reserved. 1. Introduction Little is known about microbes and symbiotic forms of fungi and algae in Antarctic soils/paleosols, beyond endolithic lichens in pebble pavement (De la Torre et al., 2003; Edwards et al., 2005) and bedrock (Rios et al., 2005) and bacteria and fungi in pedons near the Inland Ice and closer to the coast (Rivkina et al., 2000; Mahaney et al., 2001, 2009; Wood et al., 2008; Hart et al., 2011). While Antarctic habitats and microbial populations have been surveyed and studied by Wynn-Williams and Edwards (2000), the range of microbes in soils of different age and regolith habitat has yet to be fully defined. A find of fossil insects adjacent to the Inland Ice has never been reported until now; however, fossils including diatoms, palynomorphs, mosses, ostracodes, and insects related to the last tundra community inhabiting the Dry Valley mountains prior to the onset of a full polar climate is documented closer to the coast (Lewis et al., 2008). Paleoecological evidence and 40 Ar/ 39 Ar dating indicate a cooling of  8.0 1C or greater, beginning 14.0770.05 Ma, and lasting 200 kyr. Although, even today, along the coast and in the Antarctic islands, a somewhat milder climate might be conducive to produce habitat suitable for the prolifera- tion of higher forms of life. Recent documentation (Dingle et al., 1997) of Oligocene and Pliocene interglacial events on the Antarc- tic Peninsula underscore punctuated climatic amelioration parti- cularly during the early stage of warm-based glaciation. A recent discovery of exoskeletons and endoskeletons of Coleoptera species in a Middle to Early Miocene paleosol near Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/pss Planetary and Space Science 0032-0633/$ - see front matter & 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.pss.2011.11.008 n Corresponding author. Tel.: þ1 905 731 7269. E-mail addresses: arkose@rogers.com (W.C. Mahaney), kris.hart2@mail.dcu.ie (K.M. Hart), shane.oreilly8@gmail.com (S.S. O’Reilly), C.allen@qub.ac.uk (C.C.R. Allen), jmd@hwr.arizona.edu (J.M. Dohm), ronhancock@ca.inter.net (R.G.V. Hancock), brian.kelleher@dcu.ie (B.P. Kelleher), Michael.milner@sympatico.ca (M.W. Milner). Planetary and Space Science 60 (2012) 386–398