Saturday, May 18, 2019


Deep Subsurface Biosphere ─ Any Parasites?
Post #27
Donald A. Windsor

As even more information comes in on the deep subsurface biosphere, the more I wonder about generalities already made about our surface biosphere.

The deep subsurface biosphere is composed of archaea, bacteria, and eukaryotes that live underground down to great depths, even under the oceans (1 - 6). It could have more species than our surface biosphere does (2).

Six years ago I proposed that parasitism was a property of life on Earth and if it is found on extraterrestrial planets, it would be a universal property. If it were not found on other planets, then it would be a property of Earth alone (7).

So far, I have not uncovered any reports of parasites in the deep subsurface biosphere.

In 1998 I proclaimed that most of the species on Earth were parasites (8). If there are no parasites in the deep subsurface biosphere, my hypothesis would be nullified. However, I did say "on" Earth, not "in". Nevertheless, I meant "on", because I was not aware of how massive the deep subsurface biosphere is.

Another thought I advocated is that parasites produce biodiversity by stopping monocultures before they get too large (9). Some of the colonies in the deep subsurface may have monocultures. That in itself could indicate a lack of parasites.

I find this all very exciting because I thought that finding extraterrestrial life on Mars would be a test of my hypotheses (10). But now the deep subsurface biosphere may provide that test.

References cited:

1. Lawton, Graham. Earth's deep, dark secret. New Scientist 2019 May 11; 242(3229): 42-45.

2. Klein, JoAnna. Deep beneath your feet, they live in the octillions. The New York Times 2018 December 19.

3. Purkamo, Lotta. et al. Diversity and functionality of archaeal, bacterial, and fungal communities in deep archaean bedrock. FEMS Microbiology Ecology 2018; 94: 1-14.

4. D'Hondt, Steven; et al. Presence of oxygen and aerobic communities from sea floor to basement in deep-sea sediments. Nature Geoscience 2015; 8: 299-304.

5. Magnabosco, C. et al. The biomass and biodiversity of the continental subsurface. Nature Geoscience 2018 October; 11(10): 707.

6. Puente-Sánchez, Fernando. et al. Viable cyanobacteria in the deep continental subsurface. PNAS 2018 October 16; 115(42): 10702-10707.

7. Windsor, Donald A. Parasitism as a property of life. 2013 September 3. Post #2.

8. Windsor, Donald A. Most of the species on Earth are parasites. International Journal for Parasitology 1998 December; 28(12): 1939-1941.

9. Windsor, Donald A. Role of parasites in Earth's biosphere. 2017 September 30. Post #13.

10. Windsor, Donald A. Parasitism on Mars. 2015 November 8. Post #10