Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Fungus-like mycelial fossils in 2.4-billion-year-old vesicular basalt


Fungi have recently been found to comprise a significant part of the deep biosphere in oceanic sediments and crustal rocks. Fossils occupying fractures and pores in Phanerozoic volcanics indicate that this habitat is at least 400 million years old, but its origin may be considerably older. A 2.4-billion-year-old basalt from the Palaeoproterozoic Ongeluk Formation in South Africa contains filamentous fossils in vesicles and fractures. The filaments form mycelium-like structures growing from a basal film attached to the internal rock surfaces. Filaments branch and anastomose, touch and entangle each other. They are indistinguishable from mycelial fossils found in similar deep-biosphere habitats in the Phanerozoic, where they are attributed to fungi on the basis of chemical and morphological similarities to living fungi. The Ongeluk fossils, however, are two to three times older than current age estimates of the fungal clade. Unless they represent an unknown branch of fungus-like organisms, the fossils imply that the fungal clade is considerably older than previously thought, and that fungal origin and early evolution may lie in the oceanic deep biosphere rather than on land. The Ongeluk discovery suggests that life has inhabited submarine volcanics for more than 2.4 billion years.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Geological map and stratigraphic section of the Griqualand West sub-basin, showing the location of Agouron drill hole GTF01 (28° 49′ 39.7′′ S, 23° 07′ 24.1′′ E).
Figure 2: Ongeluk vesicular basalt with filamentous fossils, petrographic thin sections.
Figure 3: Ongeluk vesicle with filamentous fossils, SRXTM surface/volume renderings; Swedish Museum of Natural History X6137.
Figure 4: Calcite- and chlorite-filled fracture with filamentous fossils in Ongeluk vesicular basalt, petrographic thin section; Swedish Museum of Natural History X6133


  1. 1

    Edwards, K. J., Becker, K. & Colwell, F. The deep, dark energy biosphere: intraterrestrial life on Earth. Annu. Rev. Earth Planet. Sci. 40, 551–568 (2012).

    CAS  Article  Google Scholar 

  2. 2

    Schumann, G., Manz, W., Reitner, J. & Lustrino, M. Ancient fungal life in North Pacific Eocene oceanic crust. Geomicrobiol. J. 21, 241–246 (2004).

    Article  Google Scholar 

  3. 3

    Peckmann, J., Bach, W., Behrens, K. & Reitner, J. Putative cryptoendolithic life in Devonian pillow basalt, Rheinisches Schiefergebirge, Germany. Geobiology 6, 125–135 (2008).

    CAS  Article  Google Scholar 

  4. 4

    Eickmann, B., Bach, W., Kiel, S., Reitner, J. & Peckmann, J. Evidence for cryptoendolithic life in Devonian pillow basalts of Variscan orogens, Germany. Palaeogeogr. Palaeoclimatol. Palaeoecol. 283, 120–125 (2009).

    Article  Google Scholar 

  5. 5

    Ivarsson, M. et al. Fossilized fungi in subseafloor Eocene basalts. Geology 40, 163–166 (2012).

    CAS  Article  Google Scholar 

  6. 6

    Ivarsson, M., Bengtson, S., Skogby, H., Belivanova, V. & Marone, F. Fungal colonies in open fractures of subseafloor basalt. Geo-Mar. Lett. 33, 233–243 (2013).

    Article  Google Scholar 

  7. 7

    Ivarsson, M. et al. Zygomycetes in vesicular basanites from Vesteris Seamount, Greenland Basin – a new type of cryptoendolithic fungi. PLoS ONE 10, e0133368 (2015).

    Article  Google Scholar 

  8. 8

    Furnes, H . et al. in Modern Approaches in Solid Earth Sciences Vol. 4 (eds Dilek, Y., Furnes, H. & Muehlenbachs, K .) 1–68 (Springer, 2008).

    Google Scholar 

  9. 9

    Grosch, E. G. & McLoughlin, N. Reassessing the biogenicity of Earth’s oldest trace fossil with implications for biosignatures in the search for early life. Proc. Natl Acad. Sci. USA 111, 8380–8385 (2014).

    CAS  Article  Google Scholar 

  10. 10

    Staudigel, H., Furnes, H. & DeWit, M. Paleoarchean trace fossils in altered volcanic glass. Proc. Natl Acad. Sci. USA 112, 6892–6897 (2015).

    CAS  Article  Google Scholar 

  11. 11

    Grosch, E. G. & McLoughlin, N. Questioning the biogenicity of titanite mineral trace fossils in Archean pillow lavas. Proc. Natl Acad. Sci. USA 112, E1390–E1391 (2015).

    Article  Google Scholar 

  12. 12

    McLoughlin, N. & Grosch, E. G. A hierarchical system for evaluating the biogenicity of metavolcanic- and ultramafic-hosted microalteration textures in the search for extraterrestrial life. Astrobiology 15, 901–921 (2015).

    Article  Google Scholar 

  13. 13

    Fisk, M. & McLoughlin, N. Atlas of alteration textures in volcanic glass from the ocean basins. Geosphere 39, 317–341 (2013).

    Article  Google Scholar 

  14. 14

    Phillips, W. J. Interpretation of crystalline spheroidal structures in igneous rocks. Lithos 6, 235–244 (1973).

    CAS  Article  Google Scholar 

  15. 15

    Mcloughlin, N., Staudigel, H., Furnes, H., Eickmann, B. & Ivarsson, M. Mechanisms of microtunneling in rock substrates: distinguishing endolithic biosignatures from abiotic microtunnels. Geobiology 8, 245–255 (2010).

    CAS  Article  Google Scholar 

  16. 16

    Lepot, K., Benzerara, K. & Philippot, P. Biogenic versus metamorphic origins of diverse microtubes in 2.7 Gyr old volcanic ashes: multi-scale investigations. Earth Planet. Sci. Lett. 312, 37–47 (2011).

    CAS  Article  Google Scholar 

  17. 17

    Pasteris, J. D. & Wopenka, B. Necessary, but not sufficient: Raman identification of disordered carbon as a signature of ancient life. Astrobiology 3, 727–738 (2003).

    CAS  Article  Google Scholar 

  18. 18

    Sumner, D. Y. Poor preservation potential of organics in Meridiani Planum hematite-bearing sedimentary rocks. J. Geophys. Res. 109, E12007 (2004).

    Article  Google Scholar 

  19. 19

    Chi Fru, E. et al. Fossilized iron bacteria reveal pathway to biological origin of banded iron formation. Nat. Commun. 4, 2050 (2013).

    Article  Google Scholar 

  20. 20

    Staudigel, H., Hart, S. R. & Richardson, S. H. Alteration of the oceanic crust: processes and timing. Earth Planet. Sci. Lett. 52, 311–327 (1981).

    CAS  Article  Google Scholar 

  21. 21

    Erikson, D. The morphology, cytology, and taxonomy of the Actinomycetes. Annu. Rev. Microbiol. 3, 23–54 (1949).

    Article  Google Scholar 

  22. 22

    Higgins, M. L. & Silvey, J. K. G. Slide culture observations of two freshwater Actinomycetes. Trans. Am. Microsc. Soc. 85, 390–398 (1966).

    CAS  Article  Google Scholar 

  23. 23

    Goodfellow, M . et al. (eds) Bergey's Manual of Systematic Bacteriology Vol. 5: The Actinobacteria 2nd edn (Springer, 2012).

    Book  Google Scholar 

  24. 24

    Bull, A. T. in Extremophiles Handbook (eds Horikoshi, K. et al.) 1203–1240 (Springer, 2011).

    Book  Google Scholar 

  25. 25

    Edgcomb, V. P., Beaudoin, D., Gast, R., Biddle, J. F. & Teske, A. Marine subsurface eukaryotes: the fungal majority. Environ. Microbiol. 13, 172–183 (2011).

    CAS  Article  Google Scholar 

  26. 26

    Orsi, W., Biddle, J. F. & Edgcomb, V. Deep sequencing of subseafloor eukaryotic rRNA reveals active fungi across marine subsurface provinces. PLoS ONE 8, e56335 (2013).

    CAS  Article  Google Scholar 

  27. 27

    Sohlberg, E . et al. Revealing the unexplored fungal communities in deep groundwater of crystalline bedrock fracture zones in Olkiluoto, Finland. Front. Microbiol. 6, 573 (2015).

    Article  Google Scholar 

  28. 28

    Ivarsson, M., Bengtson, S. & Neubeck, A. The igneous oceanic crust – Earth’s largest fungal habitat? Fungal Ecol. 20, 249–255 (2016).

    Article  Google Scholar 

  29. 29

    Pachiadaki, M. G., Rédou, V., Beaudoin, D. J., Burgaud, G. & Edgcomb, V. P. Fungal and prokaryotic activities in the marine subsurface biosphere at Peru Margin and Canterbury Basin inferred from RNA-based analyses and microscopy. Front. Microbiol. 7, 846 (2016).

    Article  Google Scholar 

  30. 30

    Nicolson, T. H. Mycorrhiza in the Gramineae: I. Vesicular-arbuscular endophytes, with special reference to the external phase. J. Brit. Mycolog. Soc. 42, 421–438 (1959).

    Article  Google Scholar 

  31. 31

    Glass, N. L., Rasmussen, C., Roca, M. G. & Read, N. D. Hyphal homing, fusion and mycelial interconnectedness. Trends Microbiol. 12, 135–141 (2004).

    CAS  Article  Google Scholar 

  32. 32

    Bengtson, S. et al. Deep-biosphere consortium of fungi and prokaryotes in Eocene sub-seafloor basalts. Geobiology 12, 489–496 (2014).

    CAS  Article  Google Scholar 

  33. 33

    Ivarsson, M. et al. A fungal-prokaryotic consortium at the basalt-zeolite interface in subseafloor igneous crust. PLoS ONE 10, e0140106 (2015).

    Article  Google Scholar 

  34. 34

    Brown, J. W. & Sorhannus, U. A molecular genetic timescale for the diversification of autotrophic stramenopiles (Ochrophyta): substantive underestimation of putative fossil ages. PLoS ONE 5, e12759 (2010).

    Article  Google Scholar 

  35. 35

    Stephenson, L. W., Erwin, D. C. & Leary, J. V. Hyphal anastomosis in Phytophthora capsici. Phytopathology 64, 149–150 (1974).

    Article  Google Scholar 

  36. 36

    Sbrana, C., Nuti, M. P. & Giovannetti, M. Self-anastomosing ability and vegetative incompatibility of Tuber borchii isolates. Mycorrhiza 17, 667–675 (2007).

    Article  Google Scholar 

  37. 37

    Dowson, C. G., Boddy, L. & Rayner, A. D. M. Development and extension of mycelial cords in soil at different temperatures and moisture contents. Mycol. Res. 92, 383–391 (1989).

    Article  Google Scholar 

  38. 38

    Cavalier-Smith, T. & Chao, E. E. The opalozoan Apusomonas is related to the common ancestor of animals, fungi, and choanoflagellates. Proc. R. Soc. Lond. B 261, 1–6 (1995).

    Article  Google Scholar 

  39. 39

    James, T. Y. et al. Reconstructing the early evolution of fungi using a six-gene phylogeny. Nature 443, 818–822 (2006).

    CAS  Article  Google Scholar 

  40. 40

    Baldauf, S. L. An overview of the phylogeny and diversity of eukaryotes. J. Syst. Evol. 46, 263–273 (2008).

    Google Scholar 

  41. 41

    Heckman, D. S. et al. Molecular evidence for the early colonization of land by fungi and plants. Science 293, 1129–1133 (2001).

    CAS  Article  Google Scholar 

  42. 42

    Hedges, S. B., Blair, J. E., Venturi, M. & Shoe, J. L. A molecular timescale of eukaryote evolution and the rise of complex multicellular life. BMC Evol. Biol. 4, 2 (2004).

    Article  Google Scholar 

  43. 43

    Padovan, A. C. B., Sanson, G. F. O., Brunstein, A. & Briones, M. R. S. Fungi evolution revisited: application of the penalized likelihood method to a Bayesian fungal phylogeny provides a new perspective on phylogenetic relationships and divergence dates of Ascomycota groups. J. Mol. Evol. 60, 726–735 (2005).

    CAS  Article  Google Scholar 

  44. 44

    Bhattacharya, D ., Yoon, H. S ., Hedges, S. B. & Hackett, J. D. in The Timetree of Life (eds Hedges, S. B. & Kumar, S. ) 116–120 (Oxford Univ. Press, 2009).

    Google Scholar 

  45. 45

    Parfrey, L. W., Lahr, D. J. G., Knoll, A. H. & Katz, L. A. Estimating the timing of early eukaryotic diversification with multigene molecular clocks. Proc. Natl Acad. Sci. USA 108, 13624–13629 (2011).

    CAS  Article  Google Scholar 

  46. 46

    Taylor, T. N ., Krings, M. & Taylor, E. L. Fossil Fungi (Elsevier, 2015).

    Google Scholar 

  47. 47

    Sharpe, S. C ., Eme, L ., Brown, M. W. & Roger, A. J. in Evolutionary Transitions to Multicellular Life (eds Ruiz-Trillo, I. & Nedelcu, A. M. ) 3–29 (Springer, 2015).

    Google Scholar 

  48. 48

    Kohlmeyer, J. & Kohlmeyer, E. Marine Mycology (Academic, 1979).

    Google Scholar 

  49. 49

    Benton, M. J. et al. Constraints on the timescale of animal evolutionary history. Palaeontol. Electron. 18, 18.1.1FC (2015).

    Google Scholar 

  50. 50

    Lanari, P. et al. XMapTools: a MATLAB©-based program for electron microprobe X-ray image processing and geothermobarometry. Comput. Geosci. 62, 227–240 (2014).

    CAS  Article  Google Scholar 

  51. 51

    Bourdelle, F., Parra, T., Chopin, C. & Beyssac, O. A new chlorite geothermometer for diagenetic to low-grade metamorphic conditions. Contrib. Mineral. Petrol. 165, 723–735 (2013).

    CAS  Article  Google Scholar 

  52. 52

    Marone, F. & Stampanoni, M. Regridding reconstruction algorithm for real-time tomographic imaging. J. Synchrotron Radiat. 19, 1029–1037 (2012).

    CAS  Article  Google Scholar 

  53. 53

    Johnson, J. E., Gerpheide, A., Lamb, M. P. & Fischer, W. W. O2 constraints from Paleoproterozoic detrital pyrite and uraninite. GSA Bull. 126, 813–830 (2014).

    CAS  Article  Google Scholar 

Download references


Our work has been supported by the Agouron Institute, Swedish Research Council (2012-4364, 2013-4290), Danish National Research Foundation (DNRF53), Australian Research Council (DP110103660, DP140100512), Paul Scherrer Institute (20130185, 20141047), Australian Microscopy & Microanalysis Research Facility, National Science Foundation (EAR-05-45484), NASA Astrobiology Institute (NNA04CC09A), Natural Sciences and Engineering Research Council, and the European Commission CALIPSO programme (312284). We thank V. Belivanova for technical assistance, P. von Knorring for drafting Supplementary Fig. 6, J. Peckmann for supplying images for Supplementary Fig. 8c,d and A. Tehler for discussions.

Author information




A.B. provided the material and geological information; B.R. discovered the filamentous structures; S.B., B.R. and M.I. designed the study; S.B., B.R., M.I., J.M. and C.B. performed the investigation; S.B. and B.R. wrote the paper with input from other co-authors; and M.S. and F.M. designed and operated the TOMCAT beamline.

Corresponding authors

Correspondence to Stefan Bengtson or Birger Rasmussen.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Discussion; Supplementary Figures; Supplementary Tables (PDF 32681 kb)

Supplementary Video 1

Ongeluk vesicle with filamentous fossils. SRXTM surface/volume rendering, 32.5 µm thick virtual slice passing through specimen. Note NW-SE-trending thin veins connecting the vesicle with the surroundings. Swedish Museum of Natural History X6137, same vesicle as in Fig. 3. (MPG 25880 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Bengtson, S., Rasmussen, B., Ivarsson, M. et al. Fungus-like mycelial fossils in 2.4-billion-year-old vesicular basalt. Nat Ecol Evol 1, 0141 (2017).

Download citation

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing