Stanley Miller, Harold Urey evolution |
Abiogenesis
A “warm little pond, with all sorts of ammonia and phosphoric salts, lights, heat, electricity, etc. present, so that a protein compound was chemically formed ready to undergo still more complex changes” —Charles Darwin, on conditions for the origin of life Some people thought it was impossible; other people thought it might have happened. Miller and Urey actually did the experiment to test the “primordial soup” theory of Alexander Oparin and J. B. S. Haldane. Miller and Urey cycled a mixture of gases through an apparatus that delivered electrical sparks. This produced a variety of amino acids, building blocks of proteins. Living organisms might have evolved from such molecules.
Biogenesis, etcetera
biogenesis abiogenesis archebiosis * Henry Charlton Bastian believed he witnessed spontaneous generation of living organisms under his microscope and proposed the term biogenesis for the generation of living organisms from unliving matter. Thomas Henry Huxley, independently used biogenesis for generation from living things and abiogenesis for generation from unliving matter. Subsequently, Bastian renounced the term biogenesis and found that he could not accept the term abiogenesis so introduced the term archebiosis for the generation of living organisms from unliving matter.
Turtles
If everything living came from other living things what did the first living thing come from? What do we mean by “life,” and what do we mean by “first”? If the universe and all space were originally compressed into a single point, then where did that point come from, and what kind of thing surrounded it? Asked, if the world were on the back of a giant turtle, what the giant turtle was standing on, the foolish might have argued “It’s no use; there are turtles all the way down.”
Science gave up on the idea of spontaneous generation after Louis Pasteur did the experiment using a bottle with a swan-neck duct. As the idea of evolution began to be accepted, they wondered how life started. Many continued to rely on religious myths. Many believed that life on earth was planted from an asteroid, comet, or alien spacecraft (the panspermia hypothesis). If life didn’t start from unliving matter, then how did whatever started it start?
See also in The book of science:
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