Throughout Earth’s history, shifts in ocean redox influenced the bioavailability of trace metals, shaping the activity of microorganisms.
The last eukaryotic common ancestor (LECA) is widely thought to have been an oxygen-respiring organism, arising through endosymbiosis when a free-living bacterium became the mitochondrion.
The search for atmospheric biosignatures in Earth-like exoplanets is one of the most pressing challenges in observational astrobiology. Detecting biogenic gases in terrestrial planets requires high resolution and long integration […]
If all the world’s a stage and all the species merely players, then their exits and entrances can be found in the rock record.
The Snowball Earth hypothesis predicts global ice cover; however, previous descriptions of Cryogenian (720-635 Ma) glacial deposits are limited to continental margins and shallow marine basins.
The chemical makeup of Earth’s atmosphere during the Archean (4 Ga-2.5 Ga) and Proterozoic eon (2.5 Ga-0.5 Ga) contrast considerably with the present-day: the Archean was rich in carbon dioxide […]
Telescope missions are currently being designed which will make direct imaging of habitable exoplanets possible in the near future, and studies are needed to quantify the detectability of biosignature features […]
Exoplanet characterization missions planned for the future will soon enable searches for life beyond our solar system. Critical to the search will be the development of life detection strategies that […]
Life depends on a conserved set of chemical energy currencies that are relics of early biochemistry. One of these is ATP, a molecule that, when paired with a divalent metal […]
Stromatolites are the earliest geological record of life on Earth. These curious biotic structures are made of algae carpets growing toward the light and precipitating carbonates.
