The Alpha Road

Q: Are there any species on Earth that would be able to survive on Mars?

A: Definitely. Deinococcus radiodurans is one of the hardiest known microorganisms on the planet – it is able to withstand ionizing radiation dozes thousands of time larger than the maximum for humans. Spores of many other microbes would be able to survive there, albeit perhaps only in this dormant state. There are of course other extremophilic organisms on the planet, living in highly acidic environments, such as the river Rio Tinto in Spain, the geothermal vents of Yellowstone, the hydrothermal vents in the mid-atlantic, the dry valleys of Antarctica (McMurdo) and many, many other inhospitable for humans places, often resembling the Martian environment in some respect(s). Still, the conditions on Mars are not clearly determined (especially in the sub-surface, where life is putatively present, having retreated when the once warm and moist conditions deteriorated into a dry and UV radiation sterilized cold desert) and represent a unique environment for sure. Surviving there is one thing, but thriving would be a completely different issue. I would recommend subscribing to the Astrobiology journal, very often there are papers there concerning highly-resistant organisms and their relevance to Astrobiology. Also there are some great introductory books on Astrobiology, like the “Complete Course in Astrobiology” among others. Anything I write here will be too short to give justice to this fascinating and important question.
Forgot to mention the members of the phylum Tardigrada (or more commonly referred as water bears). Perhaps the hardiest eukaryotes out there, they can survive some time even in outer space!

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