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Biologists have been unable to agree on a definition of the complex phenomenon known as "life." In a special collection of essays in Astrobiology, a peer-reviewed journal from Mary Ann Liebert, Inc., leaders in the fields of philosophy, science, and molecular evolution present a variety of perspectives on defining life.
Here are two representative ones:
Antonio Lazcano, National Autonomous University of Mexico, and colleagues present an historical perspective of the many definitions of life put forth over the years and why they have been unsatisfactory, in the essay, "The Definition of Life: A Brief History of an Elusive Scientific Endeavor."See also this:
Steven Benner, Foundation for Applied Molecular Evolution and The Westheimer Institute for Science and Technology (Gainesville, FL), explores the various definitions of life popular in the astrobiology community and how each is connected to a "theory of life." In the essay "Defining Life," Benner describes how chemical structures capable of Darwinian evolution might be useful as universal biosignatures.
In the search for life beyond Earth, we should not expect to find life forms we're familiar with. Determining whether something completely alien is 'alive' could be a challenge, so a universal definition of life is needed. Biologists have yet to agree on a definition, but a new theory attempts to provide a solution.Why does all this remind me of an episode of The Twilight Zone?, where people go over and over things, but ...