Born On Mars: Multigenerational Phenotypic Change In Caenorhabditis Elegans Under Martian Analog Gravity And Hypomagnetic Fields
Life on Mars will require organisms to endure sustained exposure to reduced gravity and near-absent planetary magnetism, yet little is known about how these environmental factors may combine to potentially affect biology across generations.
Here, we investigated the transgenerational effects of Martian gravity and magnetism on neuromuscular, sensory, and morphological function using Caenorhabditis elegans as a model.
Animals were reared continuously under ground-based simulated Martian conditions across six generations and assessed using high-throughput behavioral and morphometric assays. Animals remained viable but acquired progressive transgenerational impairments across multiple functional domains.
Swimming frequency showed immediate and severe deficits at all generations tested (Cohen’s d = 2.6-4.2), while chemotaxis deficits emerged more gradually, becoming significant by Generation 4. Morphological changes followed non-monotonic trajectories, with transient compensatory growth at Generation 4 followed by increased developmental variability at Generation 6. These differential patterns of impairment across neuromuscular, sensory, and developmental systems reveal domain-specific vulnerabilities to sustained Martian conditions.
Critically, by Generation 6, Mars lineages exhibited a three-to-eight-fold increase in phenotypic variability, consistent with a loss of developmental canalization that could pose a more serious challenge for sustained colonization than simple mean fitness reductions.
Simulation of Mars and Earth’s magnetic and gravitational fields. A) Two clinostats were positioned at different angles to either partially cancel the Earth’s effective gravitational pull (Mars: 67.7° from horizontal) or as a control (Earth: 90° from horizontal). Two identical 20cm³ 4-coil Merritt coil magnetic cages with internal (grounded) Faraday insulation. Both coils were powered by the same amplifier and current. Each coil system was angled so that the magnetic field produced at its center combined with the local Earth field to produce a net field mimicking Mars’ magnetic field (<6 mG), or Earth’s magnetic field (650 mG). In each system 3cm agar plates containing C. elegans eggs were placed and allowed to grow to adulthood at 20°C feeding on OP50 E. coli (3.5 days). The magnetic field within the systems was tested at the start and end of each experiment and LED indicator was used throughout to monitor the system while in operation. B) Experimental design. Synchronized populations of C. elegans were maintained under simulated Earth or Mars conditions continuously for six generations. At Generations 2, 4, and 6, day 1 adults were removed for behavioral and morphological assays. Each condition was propagated through 4-5 independent biological lineages (assay plates) tracked across all generations, creating a repeated measures design for statistical analysis. — biorxiv.org
Astrobiology,
