![Bold black letters illustrate amino acids that are deduced as early by the approach, while red letters indicate late additions to the alphabet according to the approach (C* implies possible prebiotic synthesis under specific and narrow conditions [4]). Regular black letters represent amino acids that have not been resolved as either early or late by the approach. LUCA: last universal common ancestor; LECA: last eukaryotic common ancestor; rTCA: tricarboxylic acid cycle. -- Trends in Genetics](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Reconstructing.png?resize=1200%2C720&ssl=1)
[Trends in Genetics] The canonical amino acid alphabet has remained remarkably stable since life’s early stages, yet the factors that shaped its emergence remain debated. Early views emphasized prebiotic availability […]
LECA
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What The Earliest Evidence For Life Tells Us About The Early Evolution Of The Biosphere
Life emerged on Earth in an ultramafic world under anaerobic conditions and conditioned by particular environmental characteristics for which no record remains.