The possibility of past life on Mars remains uncertain. Current conditions on the planet, marked by extreme temperatures, high radiation levels, and a thin atmosphere, are far from conducive to supporting life. Yet, some lichen species found in Earth’s most inhospitable environments may have the potential to endure Mars’ harsh landscape.
Lichens are a fascinating symbiotic relationship between two organisms: a fungal component, which constitutes around 90 percent of their makeup, and a photosynthetic partner that can be either algae or cyanobacteria. A research team led by botanist Kaja Skubała sought to test the resilience of two lichen species, Diploschistes muscorum and Cetrarea aculeata, under simulated Martian conditions at the Space Research Center of the Polish Academy of Sciences.
In a study recently published in IMA Fungus, the researchers concluded, “Our study is the first to demonstrate that the metabolism of the fungal partner in lichen symbiosis was active while being in a Mars-like environment. X-rays associated with solar flares and SEPs reaching Mars should not affect the potential habitability of lichens on this planet.”
The Martian environment presents significant threats due to its ionizing radiation, which can inflict cellular damage and disrupt various biological processes. The extent of this impact varies with the organism and the intensity of radiation exposure.
Adaptations for Survival
Lichens possess unique adaptations that enhance their chances of survival in extreme environments. These include traits such as low metabolic rates, minimal nutritional requirements, and remarkable longevity. Similar to tardigrades, lichens can exist in a desiccated state for long periods until they receive water. They also produce metabolites that provide protection against ultraviolet rays and possess melanin pigments that help shield them from radiation.
