Swansong biospheres II: the final signs of life on terrestrial planets near the end of their habitable lifetimes

@article{OMalleyJames2014SwansongBI,
  title={Swansong biospheres II: the final signs of life on terrestrial planets near the end of their habitable lifetimes},
  author={Jack T. O'Malley-James and Charles S. Cockell and J. S. Greaves and John A. Raven},
  journal={International Journal of Astrobiology},
  year={2014},
  volume={13},
  pages={229 - 243}
}
Abstract The biosignatures of life on Earth do not remain static, but change considerably over the planet's habitable lifetime. Earth's future biosphere, much like that of the early Earth, will consist of predominantly unicellular microorganisms due to the increased hostility of environmental conditions caused by the Sun as it enters the late stage of its main sequence evolution. Building on previous work, the productivity of the biosphere is evaluated during different stages of biosphere… 
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