Evolutionary Processes Transpiring in the Stages of Lithopanspermia

Area of Science:

• Astrobiology
• Planetary Science
• Evolutionary Biology

Background:

• Lithopanspermia proposes natural transfer of life between celestial bodies via impacts.
• Previous research focused on the physics and survival probabilities of life during transport.
• Life's active response and evolutionary adaptation during these stages were underexplored.

Purpose of the Study:

• To investigate how the stages of lithopanspermia can actively drive evolutionary processes in transported organisms.
• To explore the potential for increased stress tolerance and invasive capabilities in microbes subjected to interplanetary travel.
• To consider implications for planetary protection protocols and the search for extraterrestrial life.

Main Methods:

• Analysis of the physical and biological factors involved in planetary ejection, interplanetary transport, and planetary entry.
• Modeling the selective pressures encountered by microbial life during these stages.
• Comparative analysis of natural lithopanspermia and artificial spacecraft-mediated panspermia.

Main Results:

• The stresses of lithopanspermia can act as evolutionary drivers, potentially increasing microbial robustness and survival capacities.
• Organisms surviving the transport stages may exhibit higher tolerance to pressure and heat shock than their initial populations.
• Spacecraft-mediated panspermia could similarly enhance the stress tolerance of hitchhiking organisms, increasing their invasive potential.

Conclusions:

• Lithopanspermia stages can facilitate evolution, leading to more robust bacteria with enhanced survival abilities.
• The process may increase the invasive potential of terrestrial organisms transported to other worlds.
• Planetary protection protocols need to account for the evolutionary enhancement of life during interplanetary transit.