tumbleweed41
Resident Liberal Hippie
In the early history of the Earth, life as we know it would have been impossible. Methane, hydrogen, ammonia and water were present, but very little to no free oxygen.
In 1952 Stanley Miller and Harold Urey set up an experiment based on the hypothesis of Alexander Oparin and J. B. S. Haldane that conditions on the primitive Earth favored chemical reactions that synthesized organic compounds from inorganic precursors.
Using the elements that were abundant on the earth at the time of the hypothesized origin of life, Urey and Miller introduced simulated lighting to this prebiotic 'soup'.
In 1953 they published their findings. They found that at least five differing amino acids were formed. In 2008 a reanalysis of the Urey-Miller experiment found that 22 amino acids were formed, rather than 5, in the in one of the apparatus used in the original experiment. Sugars, lipids, and some of the building blocks for nucleic acids were also formed.
Jeffery Bada recently performed tests similar to the Urey-Miller experiment. He found that while carbon dioxide and nitrogen that were present in that early atmosphere may have created amino acid destroying nitrates, iron and carbonate materials also believed to be present would have neutralized the nitrates, and would result in a significant amount of amino acids surviving.
An interesting note is that in 1969, the Murchison meteorite that fell in Australia was found to contain over 90 different amino acids. 19 of which are also found in Earth lifeforms. Showing that the production of amino acids, the very building blocks needed for carbon based life, are not limited to Earth.
Also giving some credence to the panspermia hypothesis that our original building blocks may very well have come from somewhere beyond our own solar system.
As a science, abiogenesis is still seriously underdeveloped in its explanatory power, despite the recent progress. Continuing research will provide more answers, and may give some surprising results. But that is what scientific research is all about. Looking for the correct answers to our biggest questions, no matter what those answers may be. Not looking for the answers we want.
In 1952 Stanley Miller and Harold Urey set up an experiment based on the hypothesis of Alexander Oparin and J. B. S. Haldane that conditions on the primitive Earth favored chemical reactions that synthesized organic compounds from inorganic precursors.
Using the elements that were abundant on the earth at the time of the hypothesized origin of life, Urey and Miller introduced simulated lighting to this prebiotic 'soup'.
In 1953 they published their findings. They found that at least five differing amino acids were formed. In 2008 a reanalysis of the Urey-Miller experiment found that 22 amino acids were formed, rather than 5, in the in one of the apparatus used in the original experiment. Sugars, lipids, and some of the building blocks for nucleic acids were also formed.
Jeffery Bada recently performed tests similar to the Urey-Miller experiment. He found that while carbon dioxide and nitrogen that were present in that early atmosphere may have created amino acid destroying nitrates, iron and carbonate materials also believed to be present would have neutralized the nitrates, and would result in a significant amount of amino acids surviving.
An interesting note is that in 1969, the Murchison meteorite that fell in Australia was found to contain over 90 different amino acids. 19 of which are also found in Earth lifeforms. Showing that the production of amino acids, the very building blocks needed for carbon based life, are not limited to Earth.
Also giving some credence to the panspermia hypothesis that our original building blocks may very well have come from somewhere beyond our own solar system.
As a science, abiogenesis is still seriously underdeveloped in its explanatory power, despite the recent progress. Continuing research will provide more answers, and may give some surprising results. But that is what scientific research is all about. Looking for the correct answers to our biggest questions, no matter what those answers may be. Not looking for the answers we want.
