Skip to main content Accessibility help

Swansong biospheres II: the final signs of life on terrestrial planets near the end of their habitable lifetimes

  • Jack T. O'Malley-James (a1), Charles S. Cockell (a2), Jane S. Greaves (a1) and John A. Raven (a3)


The biosignatures of life on Earth do not remain static, but change considerably over the planet's habitable lifetime. Earth's future biosphere, much like that of the early Earth, will consist of predominantly unicellular microorganisms due to the increased hostility of environmental conditions caused by the Sun as it enters the late stage of its main sequence evolution. Building on previous work, the productivity of the biosphere is evaluated during different stages of biosphere decline between 1 and 2.8 Gyr from present. A simple atmosphere–biosphere interaction model is used to estimate the atmospheric biomarker gas abundances at each stage and to assess the likelihood of remotely detecting the presence of life in low-productivity, microbial biospheres, putting an upper limit on the lifetime of Earth's remotely detectable biosignatures. Other potential biosignatures such as leaf reflectance and cloud cover are discussed.


Corresponding author


Hide All
Ajtay, G.L., Ketner, P. & Duvigneaud, P. (1979). Terrestrial primary production and phytomass. In The Global Carbon Cycle. Scope 13, ed. Bolin, B.Degens, E.T.Kempe, S. & Ketner, P., pp. 129181. John Wiley and Sons Ltd, Chichester.
Albert, V.A., Jobson, R.W., Michael, T.P. & Taylor, D.J. (2010). The carnivorous bladderwort (Utricularia, Lentibulariaceae): a system inflates. J. Exp. Bot. 61, 59.
Allison, S.D. (2006). Brown ground: a soil carbon analogue for the green world hypothesis? Am. Natur. 167, 619627.
Anten, N.P.R., Schieving, F., Medina, E., Werger, M.J.A. & Schufflen, P. (1995). Optimal leaf area indices in C3 and C4 mono- and dicotyledonous species at low and high nitrogen availability. Physiologia Plantarum 95, 541550.
Arakaki, M., Christin, P-A., Nyffeler, R., Lendei, A., Eggli, U., Matthew Ogburn, R., Spriggs, E., Moore, M.J. & Edwards, E.J. (2011). Contemporaneous and recent radiations of the world's major succulent plant lineages. Proc. Natl. Acad. Soc. USA 108, 83798384.
Bailey, J. (2007). Rainbows, polarization, and the search for habitable planets. Astrobiology 7, 320332.
Barnes, R.O. & Goldberg, E.D. (1976). Methane production and consumption in anoxic marine sediments. Geology 4, 297300.
Bender, M. & Conrad, R. (1994). Microbial oxidation of methane, ammonium and carbon monoxide, and turnover of nitrous oxide and nitric oxide in soils. Biogeochemistry 27, 97112.
Benneke, B. & Seager, S. (2012). Atmospheric retrieval for super-earths: uniquely constraining the atmospheric composition with transmission spectroscopy. Astrophys. J. 753, 100121.
Bernhard, A. (2012). The nitrogen cycle: processes, players, and human impact. Nature Educ. Knowl. 3, 25.
Blair, C.C., D'Hondt, S., Spivack, A.J. & Kingsley, R.H. (2007). Radiolytic hydrogen and microbial respiration in subsurface sediments. Astrobiology 7, 951970.
Bohlen, S.R. (1987). Pressure–temperature–time paths and a tectonic model for the evolution of granulites. J. Geol. 95, 617632.
Bongers, L. (1970). Energy generation and utlization in hydrogen bacteria. J. Bacteriol. 104, 145151.
Boyd, E.S., Lange, R.K., Mitchell, A.C., Havig, J.R., Hamilton, T.L., Lafrenière, M.J., Shock, E.L., Peters, J.W. & Skidmore, M. (2011). Diversity, abundance, and potential activity of nitrifying and nitrate-reducing microbial assemblages in a subglacial ecosystem. Appl. Environ. Microbiol. 77, 47784787.
Burton, M.R., Sawyer, G.M. & Granieri, D. (2013). Deep carbon emissions from volcanoes. Rev. Mineral. Geochem. 75, 323354.
Byrne, N. et al. . (2009). Presence and activity of anaerobic ammonium-oxidizing bacteria at deep-sea hydrothermal vents. ISME J. 3, 117123.
Caldeira, C. & Kasting, J.F. (1992). The life span of the biosphere revisited. Nature 360, 721–273.
Canfield, D.E. (2005). The early history of atmospheric oxygen: homage to Robert M. Garrels. Annu. Rev. Earth Planet. Sci. 33, 136.
Chen, Y., Wu, L., Boden, R., Hillebrand, A., Kumaresan, D., Moussard, H., Baciu, M., Lu, Y. & Murrell, J.C. (2009). Life without light: microbial diversity and evidence of sulfur- and ammonium-based chemolithotrophy in Movile Cave. ISME J. 3, 10931104.
Cnossen, I., Sanz-Forcada, J., Favata, F., Witasse, O., Zegers, T. & Arnold, N.F. (2007). Habitat of early life: solar X-ray and UV radiation at earth's surface 4–3.5 billion years ago. J. Geophys. Res. Planets 112, E02008.
Cockell, C.S. (1999). Life on Venus. Planet. Space Sci. 47, 14871501.
Cockell, C.S. & Airo, A. (2002). On the plausibility of a UV transparent biochemistry. Orig. Life Evol. B 32, 255274.
Cockell, C.S. & Raven, J.A. (2007). Ozone and life on the Archaean Earth. Phil. Trans. R. Soc. A 365, 18891901.
Courtillot, V., Davaille, A., Besse, J. & Stock, J. (2003). Three distinct types of hotspots in the Earth's mantle. Earth Plan. Sci. Lett. 205, 295308.
Dalsgaard, T., Canfield, D.E., Petersen, J., Thamdrup, B. & Acuña-González, J. (2003). N2 production by the anammox reaction in the anoxic water column of Golfo Dulce, Costa Rica. Nature 422, 606608.
DeLeon-Rodriguez, N., Lathem, T.L., Rodriguez-R, L.M., Barazesh, J.M., Anderson, B.E., Beyersdorf, A.J., Ziemba, L.D., Bergin, M., Nenes, A. & Konstantinidis, K.T. (2013). Microbiome of the upper troposphere: species composition and prevalence, effects of tropical storms, and atmospheric implications. Proc. Natl. Acad. Soc. USA 110, 25752580.
Deng, F., Chen, J.M., Plummer, S., Chen, M. & Pise, J. (2006). Algorithm for global leaf area index retrieval using satellite imagery. IEEE Trans. Geosci. Remote Sens. 44, 22192229.
Des Marais, D.J., Harwitt, M.O., Jucks, K.W., Kasting, J.F., Lin, D.N.C., Lunine, J.I., Schneider, J., Seager, S., Traub, W.A. & Woolf, N.J. (2002). Remote sensing of planetary properties and biosignatures on extrasolar terrestrial planets. Astrobiology 2, 153181.
Domagal-Goldman, S., Meadows, V.S., Claire, M.W. & Kasting, J.F. (2011). Using biogenic sulfur gases as remotely detectable biosignatures on anoxic planets. Astrobiology 11, 419441.
Durieux, L., Machado, L.A.T. & Laurent, H. (2003). The impact of deforestation on cloud cover over the Amazon arc of deforestation. Remote Sens. Environ. 86, 132140.
Ehhalt, D.H. (1974). The atmospheric cycle of methane. Tellus 26, 5870.
Elvidge, C.D. & Lyon, R.J.P. (1985). Influence of rock-soil spectral variation on the assessment of green biomass. Remote Sens. Environ. 17, 265269.
Elwood Madden, M.E., Leeman, J.R., Root, M.J. & Gainey, S. (2011). Reduced sulfur–carbon–water systems on Mars may yield shallow methane hydrate reservoirs. Planet. Space. Sci. 59, 203206.
Ferry, J.G. (2002). Methanogenesis biochemistry. In: Encyclopedia of Life Sciences, John Wiley & Sons, Ltd. Available online at
Field, C.B., Behrenfeld, M.J., Randerson, J.T. & Falkowski, P. (1998). Primary production of the biosphere: integrating terrestrial and oceanic components. Science 281, 237240.
Filella, I. & Peñuelas, J. (1994). The red edge position and shape as indicators of plant chlorophyll content, biomass and hydric status. Int. J. Remote Sens. 15, 14591470.
Fischer, T.P. (2008). Fluxes of volatiles (H2O, CO2, N2, Cl, F) from arc volcanoes. Geochem. J. 42, 2138.
Flynn, K.J., Stoecker, D.K., Mitra, A., Raven, J.A., Glibert, P.M., Hansen, P.J., Granéli, E. & Burkholder, J.M. (2013). A case of mistaken identification: the importance of mixotrophs and the clarification of plankton functional-classification. J. Plankton Res. 35, 311.
Ford, E.B., Seager, S. & Turner, E.L. (2003). A model of the temporal variability of optical light from extrasolar terrestrial planets. Astronomical Society of the Pacific Conf. Series vol. 294, pp. 639644.
Ganguly, S. et al. . (2012). Generating global leaf area index from landsat: algorithm formulation and demonstration. Remote Sens. Environ. 122, 185202.
Gantt, B., Meskhidze, N. & Kamykowski, D. (2009). A new physically-based quantification of marine isoprene and primary organic aerosol emissions. Atmos. Chem. Phys. 9, 49154927.
Gardner, J.P. et al. . (2006). The James Webb space telescope. Space Sci. Rev. 123, 485606.
Geib, S.M., Filley, T.R., Hatcher, P.G., Hoover, K., Carlson, J.E., Jimenez-Gasco, M., Nakagawa-Izumi, A., Sleighter, R.L. & Tien, M. (2008). Lignin degradation in wood-feeding insects. Proc. Natl. Acad. Soc. USA 105, 1293212937.
Gilmozzi, R. & Spyromilio, J. (2007). The European extremely large telescope (E-ELT). Messenger 127, 1119.
Girguis, P.R., Orphan, V.J., Hallam, S.J. & DeLong, E.F. (2003). Growth and methane oxidation rates of anaerobic methanotrophic archaea in a continuous-flow bioreactor. Appl. Environ. Microbiol. 69, 54725482.
Givnish, T.J., Burkhardt, E.L., Happel, R.E. & Weintraub, J.D. (1984). Carnivory in the bromeliad Brocchiniareducta, with a cost/benefit model for the general restriction of carnivorous plants to sunny, moist, nutrient-poor habitats. Am. Natur. 124, 479497.
Goldblatt, C. & Watson, A.J. (2012). The runaway greenhouse: implications for future climate change, geoengineering and planetary atmospheres. Phil. Trans. R. Soc. A 370, 41974216.
Goldblatt, C., Robinson, T.D., Zahnle, K.J. & Crisp, D. (2013). Low simulated radiation limit for runaway greenhouse climates. Nature Geosci. 6, 661667.
Grinspoon, D.H. & Bullock, M.A. (2003). Searching for evidence of past oceans on Venus. BAAS 39, 540.
Groombridge, B. & Jenkins, M.D. (2002). Global Biodiversity: Earth's Living Resources in the 21st Century. University of California Press, Berkeley and Los Angeles, California.
Halmer, M.M., Schmincke, H.-U. & Graf, H.-F. (2002). The annual volcanic gas input into the atmosphere, in particular into the stratosphere: a global data set for the past 100 years. J. Volcanol. Geoth. Res. 115, 511528.
Hegde, S. & Kaltenegger, L. (2013). Colors of extreme exo-Earth environment. Astrobiology 13, 4756.
Huete, A.R., Jackson, R.D. & Post, D.F. (1985). Spectral response of a plant canopy with different soil backgrounds. Remote Sens. Environ. 17, 3753.
Jones, H.G. (2013). Plants and Microclimate. A Quantitative Approach to Environmental Plant Physiology, 3rd edn, Cambridge University Press, Cambridge, ISBN 978-0-521-27959-8 Paperback.
Kallistova, A.Y., Kevbrina, M.V., Nekrasova, V.K., Glagolev, M.V., Serebryanaya, M.I. & Nozhevnikova, A.N. (2005). Methane oxidation in landfill cover soil. Microbiology 74, 608614.
Kallmeyer, J., Pockalny, R., Adhokari, R.R., Smith, D.C. & D'Hondt, S. (2012). Global distribution of microbial abundance and biomass in subseafloor sediment. Proc. Natl. Acad. Soc. USA 109, 1621316216.
Kaltenegger, L., Traub, W.A. & Jucks, K.W. (2007). Spectral evolution of an Earth-like planet. Astrophys. J. 658, 598615.
Kaltenegger, L. et al. . (2010). Deciphering spectral fingerprints of habitable exoplanets. Astrobiology 10, 89102.
Kasting, J.F. (1988). Runaway and moist greenhouse atmospheres and the evolution of Earth and Venus. Icarus 74, 472494.
King, A.J., Cragg, S.M., Li, Y., Dymond, J., Guille, M.J., Bowles, D.J., Bruce, N.C., Graham, I.A. & McQueen-Mason, S.J. (2010). Molecular insight into lignocellulose digestion by a marine isopod in the absence of gut microbes. Proc. Natl. Acad. Sci. USA 107, 53455350.
Kopparapu, R.K., Ramirez, R., Kasting, J.F., Eymet, V., Robinson, T.D., Mahadevan, S., Terrien, R.C., Domagal-Goldman, S., Meadows, V. & Deshpande, R. (2013). Habitable zones around main sequence stars: new estimates. Astrophys. J. 765, 131.
Koropatkin, N.M., Koppenaal, D.W., Pakrasi, H.B. & Smith, T.J. (2007). The Structure of a cyanobacterial bicarbonate transport protein, CmpA*. J. Biol. Chem. 282, 26062614.
Lawson, P.R. et al. . (2008). Terrestrial planet finder interferometer: 2007–2008 progress and plans. ‘Terrestrial Planet Finder Interferometer: 2007–2008 progress and plans’. In Proc. SPIE 7013, Optical and Infrared Interferometry, 70132N (July 14 2008); doi:10.1117/12.786822.
Leake, J.R. & Cameron, D.D. (2010). Physiological ecology of mycoheterotrophy. New Phytol. 185, 601605.
Liu, D.Y., Ding, W.X., Jia, Z.J. & Ca, Z.C. (2011). Relation between methanogenic archaea and methane production potential in selected natural wetland ecosystems across China. Biogeosciences 8, 329338.
Longbottom, R. & Kolbeinsen, L. (2008). Proc. 4th Ulcos Seminar.
Lovelock, J.E. & Whitfield, M. (1982). Life span of the biosphere. Nature 296, 561563.
Lu, J., Vecchi, G.A. & Reichler, T. (2007). Expansion of the Hadley cell under global warming. Geophys. Res. Lett. 34, L06805.
Lynch, R.C., King, A.J., Farías, M.E., Sowell, P., Vitry, C. & Schmidt, S.K. (2012). The potential for microbial life in the highest elevation (>6000 m a.s.l.) mineral soils of the Atacama region. J. Geophys. Res. 117, G02028.
Mahli, Y. (2002). Carbon in the atmosphere and terrestrial biosphere in the 21st century. Phil. Trans. R. Soc. Lond. A 360, 29252945.
Maimaiti, J., Zhang, Y., Yang, J., Cen, Y-P., Layzell, D.B., Peoples, M. & Dong, Z. (2007). Isolation and characterization of hydrogen-oxidizing bacteria induced following exposure of soil to hydrogen gas and their impact on plant growth. Env. Microbiol. 9, 435444.
Mancinelli, R.L. (1995). The regulation of methane oxidation in soil. Appl. Environ. Microbiol. 49, 581605.
McMahon, S., Parnell, J. & Blamey, N.J.F. (2013). Sampling methane in basalt on Earth and Mars. Int. J. Astrobiol. 12, 113122.
McMillan, M. & Rushforth, S.R. (1985). The diatom flora of a steam vent of Kilauea crater, Island of Hawaii. Pacific Sci. 39, 294301.
Miller-Ricci, E. & Fortney, J.J. (2010). The nature of the atmosphere of the transiting super-earth GJ 1214b. Astrophys. J. Lett. 716, L74L79.
Möhler, O., Demott, P.J., Vali, G. & Levin, Z. (2007). Microbiology and atmospheric processes: the role of biological particles in cloud physics. Biosci. Discuss. 4, 25592591.
Mooney, H.A. (1972). The carbon balance of plants. Annu. Rev. Ecol. System. 3, 315346.
Mumma, M.J., Villanueva, G.L., Novak, R.E., Hewagama, T., Bonev, B.P., DiSanti, M.A., Avi, M., Mandell, A.M. & Smith, M.D. (2009). Strong release of methane on mars in northern summer 2003. Science 323, 10411045.
Nicholas Hewitt, C. & Davison, B. (1997). Field measurements of dimethyl sulphide and its oxidation products in the atmosphere. Phil. Trans. R. Soc. Lond. B 352, 183189.
O'Malley-James, J.T., Greaves, J.S., Raven, J.A. & Cockell, C.S. (2013). Swansong biospheres: refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes. Int. J. Astrobiol. 12, 99112.
Orphan, V.J., Hinrichs, K.-U., Ussler, W., Paull, C.K., Taylor, L.T., Sylva, S.P., Hayes, J.M. III & Delong, E.F. (2001). Comparative analysis of methane-oxidizing Archaea and sulfate-reducing bacteria in anoxic marine sediments. Appl. Environ. Microbiol. 67, 19221934.
Oze, C., Jones, L.C., Goldsmith, J.I. & Rosenbauer, R.J. (2012). Differentiating biotic from abiotic methane genesis in hydrothermally active planetary surfaces. Proc. Natl. Acad. Sci. USA 109, 97509754.
Pallé, E., Osorio, M.R.Z., Barrena, R., Montañés-Rodríguez, P. & Martín, E.L. (2009). Earth's transmission spectrum from lunar eclipse observations. Nature 459, 814816.
Palmer, P.I., Jacob, D.J., Fiore, A.M. & Martin, R.V. (2003). Mapping isoprene emissions over North America using formaldehyde column observations from space. J. Geophys. Res. 108, 4180.
Pilcher, C.B. (2003). Biosignatures of early Earths. Astrobiology 3, 471486.
Pinto, J.P., Randall Gladstone, G. & Yung, Y.L. (1980). Photochemical production of formaldehyde in earth's primitive atmosphere. Science 210, 183185.
Porembski, S., Theisen, I. & Barthlott, W. (2006). Biomass allocation patterns in terrestrial, epiphytic and aquatic species of Utricularia (Lentibulariaceae). Flora – Morophol. Distrib. Fuct. Ecol. Plants 201, 477482.
Raven, J.A., Beardall, J., Flynn, K.J. & Maberly, S.C. (2009). Phagotrophy in the origins of photosynthesis in eukaryotes and as a complementary mode of nutrition in phototrophs: relation to Darwin's Insectivorous Plants. J. Exp. Bot. 60, 39753987.
Raven, J.A., Giordano, M., Beardall, J. & Maberly, S.C. (2012). Algal evolution in relation to atmospheric CO2: carboxylases, carbon-concentrating mechanisms and carbon oxidation cycles. Phil. Trans. R. Soc. B 367, 493507.
Reith, F. (2012). Life in the deep subsurface. Geology 39, 287288.
Ribas, I., Guinan, E.F., Gúdel, M. & Audard, M. (2005). Evolution of solar activity over time and effects on planetary atmospheres. I. high-energy iraddiances (1–1700 Å). Astrophys. J. 622, 680694.
Rice, B. (2002). Carnivorous plants: classic perspectives and new research. Biologist 49, 245249.
Rosenfeld, D., Rudich, Y. & Lahav, R. (2001). Desert dust suppressing precipitation: a possible desertification feedback loop. Proc. Natl. Acad. Sci. USA 98, 59755980.
Running, S.W., Peterson, D.L., Spanner, M.A. & Teuber, K.B. (1986). Remote sensing of coniferous forest leaf area. Ecology 67, 273276.
Rushby, A.J., Claire, M.W., Osborn, H. & Watson, A.J. (2013). Habitable zone lifetimes of exoplanets around main sequence stars. Astrobiology 13, 833849.
Sagan, C. & Morowitz, H. (1967). Life in the clouds of Venus. Nature 215, 12591260.
Sagan, C. & Saltpeter, E.E. (1976). Particles, environments, and possible ecologies in the Jovian atmosphere. Astrophys. J. 32, 737755.
Sage, R.F. & Zhu, X-G. (2011). Exploiting the engine of C4 photosynthesis. J. Exp. Bot. 62, 29893000.
Santosh, M. (2010). A synopsis of recent conceptual models on supercontinent tectonics in relation to mantle dynamics, life evolution and surface environment. J.Geodyn. 50, 116133.
Sawyer, C.N. & McCarty, P.L. (1967). Chemistry for Sanitary Engineers. McGraw-Hill Book Company Inc. pp. 446447.
Schmidt, S., Raven, J.A. & Paungfoo-Lonhienne, C. (2013). The mixotrophic nature of photosynthetic plants. Funct. Plant Biol. 40, 425438.
Schrenk, M.O., Edwards, K.J., Goodman, R.M., Hamers, R.J. & Banfield, J.F. (1998). Science 279, 15191522.
Schulze-Makuch, D., Grinspoon, D.H., Abbas, O., Irwin, L.N. & Bullock, M.A. (2004). A sulfur-based survival strategy for putative phototrophic life in the Venusian atmosphere. Astrobiology 4, 1118.
Seager, S., Schrenk, M. & Bains, W. (2012). An astrophysical view of earth-based metabolic Biosignature gases. Astrobiology 12, 6182.
Selsis, F. (2004). The atmosphere of terrestrial exoplanets: detection and characterization. Extrasolar Planets: Today and Tomorrow, ASP Conference Series vol. 321, pp. 170182.
Showman, A.P., Cho, J.Y-K. & Menou, K. (2010). Atmospheric circulation of extrasolar planets. In Exoplanets, ed. Seager, S., pp. 471516. University of Arizona Press, Tucson, Arizona.
Siebert, L., Simkin, T. & Kimberly, P. (2010). Volcanoes of the Word, 4th edn, University of California Press, Berkley and Los Angeles, CA.
Smith, L.A., Jim Hendry, M., Wassenaar, L.I. & Lawrence, J. (2012). Rates of microbial elemental sulfur oxidation and 18O and 34S isotopic fractionation under varied nutrient and temperature regimes. Appl. Geochem. 27, 186196.
Smrekar, S.E., Stofan, E.R., Mueller, N., Treiman, A., Elkins-Tanton, L., Herbert, J., Piccioni, G. & Drossart, P. (2010). Recent hotspot volcanism on Venus from VIRTIS emissivity data. Science 328, 605608.
Sørensen, J. (1982). Reduction of ferric iron in anaerobic marine sediment and interaction with reduction of nitrate and sulfate. Appl. Environ. Microbiol. 43, 319323.
Stephenson, R.F. (1997). Historical Eclipses and Earth's Rotation. Cambridge University Press, Cambridge, UK.
Stevens, T.O. (1997). Subsurface Lithoautotrophic Microbial Ecosystems (SLMEs) in igneous rocks: prospects for detection. In Proc. SPIE 3111 Instruments, Methods, and Missions for the Investigation of Extraterrestrial Microorganisms, pp. 358365.
Straub, K.L., Benz, M., Schink, B. & Widdel, F. (1996). Anaerobic, nitrate-dependent microbial oxidation of ferrous iron. Appl. Environ. Microbiol. 62, 14581460.
Strous, M. et al. . (2006). Deciphering the evolution and metabolism of an anammox bacterium from a community genome. Nature 440, 790794.
Suzuki, I., Takeuchi, T.L., Yuthasastrakosol, T.D. & Oh, J.K. (1990). Ferrous iron, and sulfur, oxidation and ferric iron reduction activities of Thiobacillus ferrooxidans are affected by growth on ferrous iron sulfur or a sulfide ore. Appl. Environ. Microbiol. 56, 16201626.
Suzuki, I., Chan, C.W. & Takeuchi, T.L. (1992). Oxidation of elemental sulfur to sulfite by Thiobacillus thiooxidans cells. Appl. Environ. Microbiol. 58, 37673769.
Tartakovsky, B., Manuel, M.-F. & Guiot, S.R. (2005). Degradation of trichloroethylene in a coupled anaerobic–aerobic bioreactor: modeling and experiment. Biochem. Eng. J. 26, 7281.
Teske, A.P. (2005). The deep subsurface biosphere is alive and well. TRENDS Microbiol. 13, 402404.
Tie, X., Zhang, R., Brasseur, G. & Lie, W. (2002). Global NOx production by lightning. J. Atmos. Chem. 43, 6174.
Tinetti, G. & EChO Team (2012). EChO – exoplanet characterisation observatory. Exp. Astron. 34, 311353.
Tolli, J.D., Sievert, S.M. & Taylor, C.D. (2006). Unexpected diversity of bacteria capable of carbon monoxide oxidation in a coastal marine environment, and contribution of the roseobacter-associated clade to total CO oxidation. Appl. Environ. Microbiol. 72, 19661973.
Ulloa, O., Canfield, D.E., DeLong, E.F., Letelier, R.M. & Stewart, F.J. (2012). Microbial oceanography of anoxic oxygen minimum zones. Proc. Natl. Acad. Sci. USA 109, 1599616003.
Walker, J.C.G. (1991). Feedback processes in the biogeochemical cycles of carbon. In Scientists on Gaia, ed. Schneider, S.H. & Boston, P.J., pp. 183190. The MIT Press, Cambridge, Massachusetts.
Wakefield, A.E., Gotelli, N.J., Wittman, S.E. & Ellison, A.M. (2005). Prey addition alters nutrient stoichiometry of the carnivorous plant Sarracenia purpurea. Ecology 86, 17371743.
Wardell, L.J., Kyle, P.R. & Chaffin, C. (2004). Carbon dioxide and carbon monoxide emission rates from an alkaline intra-plate volcano: Mt. Erebus Antarctica. J. Volcanol. Geoth. Res. 131, 109121.
Webster, C.R., Mahaffy, P.R., Atreya, S.K., Flesch, G.J., Christensen, L.E., Farley, K.A. & MSL Science Team (2013). Measurements of Mars Methane at Gale crater by the SAM tunable laser spectrometer on the curiosity rover. 44th Lunar and Planetary Science Conf. held March 18–22, 2013 in The Woodlands, Texas. LPI Contribution 1719: 1366.
Whitman, W.B., Coleman, D.C. & Wiebe, W.J. (1998). Prokaryotes: the unseen majority. Proc. Natl. Acad. Sci.USA 95, 65786583.
Williams, D. & Kasting, J.F. (1997). Habitable planets with high obliquities. Icarus 129, 254267.
Winter, K. & Smith, J.A.C. (eds) (1996). Crassulacean Acid Metabolism. Biochemistry, Ecphysiolgy and Evolution. Springer, Berlin.
Yoshida, M. & Santosh, M. (2011). Future supercontinent assembled in the northern hemisphere. Terra Nova 23, 333338.
Zahnle, K., Freedman, R.S. & Catling, D.C. (2011). Is there methane on Mars? Icarus 212, 493503.
Zarzycki, J., Axen, S.D., Kinney, J.N. & Kerfeld, C.A. (2013). Cyanobacterial-based approaches to improving photosynthesis in plants. J. Exp. Bot. 64, 787798.
Zhou, Z., Takaya, N., Nakamura, A., Yamaguchi, M., Takeo, K. & Shoun, H. (2002). Ammonia fermentation, a novel anoxic metabolism of nitrate by fungi. J. Biol. Chem 277, 18921896.
Zuo, Y. & Jones, R.D. (1996). Photochemical production of carbon monoxide in authentic rainwater. Geophys. Res. Lett. 23, 27692772.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

International Journal of Astrobiology
  • ISSN: 1473-5504
  • EISSN: 1475-3006
  • URL: /core/journals/international-journal-of-astrobiology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed