Reduced Diversity of Life Around Proxima Centauri and TRAPPIST-1

Abstract

The recent discovery of potentially habitable exoplanets around Proxima Centauri and TRAPPIST-1 has attracted much attention due to their potential for hosting life. We delineate a simple model that accurately describes the evolution of biological diversity on Earth. Combining this model with constraints on atmospheric erosion and the maximal evolutionary timescale arising from the star's lifetime, we arrive at two striking conclusions: (i) Earth-analogs orbiting low-mass M-dwarfs are unlikely to be inhabited, and (ii) K-dwarfs and some G-type stars are potentially capable of hosting more complex biospheres than the Earth. Hence, future searches for biosignatures may have higher chances of success when targeting planets around K-type stars.

Accepted for publication in The Astrophysical Journal Letters; 7 pages, 1 figure

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Cited by in corpus (7)

• Risks for life on habitable planets from superflares of their host stars
• Differentiating Modern and Prebiotic Earth Scenarios for TRAPPIST-1e: High-resolution Transmission Spectra and Predictions for JWST
• The Propitious Role of Solar Energetic Particles in the Origin of Life
• Active Galactic Nuclei: Boon or Bane for Biota?
• Observation of a possible superflare on Proxima Centauri
• A Birth-Death-Migration Model for Life in Astrophysical Environments
• Discovery of a transiting hot water-world candidate orbiting Ross 176 with TESS and CARMENES