Oberlin College Archives

Biosignatures & Paleobiology, Microbiology & Virology, Origin & Evolution of Life, Press Release

A Window Into Evolution – Before The Tree Of Life

by Keith CowingFebruary 6, 2026February 6, 2026

All life on Earth shares a common ancestor that lived roughly four billion years ago. This so-called “last universal common ancestor” represents the most ancient organism that researchers can study.

A general progression of the origin and early evolution of life and the scientific approaches that address each stage. The Protobiological Geochemistry stage, sometimes referred to as protometabolism or chemical evolution, depicts abiotic chemistry in a geochemical context that produced complex organic compounds and prebiotic macromolecules. The Early Genetic Inheritance/Simple Protocells stage depicts an early lifeform with a simple genetic system such as proposed by the RNA World hypothesis encapsulated within membranes that form and divide spontaneously. The Early Cellular Life stage depicts organisms with the level of complexity similar to that of the LUCA. While this final stage may be studied through so-called top–down methods, earlier stages may only be accessed through nonhistorical bottom–up approaches. -- PNAS

Astrobiology (general), Origin & Evolution of Life, Press Release

Scientists Outline A New Strategy For Understanding The Origin Of Life

by Keith CowingAugust 15, 2023August 15, 2023

Despite decades of progress, the origin of life remains one of the great unsolved problems in science. “The most basic features of biology, that organisms are made of cells, that […]