Chapter 02 - Making Life's Molecules

How did adherents of Darwin's Theory of Evolution by natural processes get around Pasteur's experiments that proved living did not arise by spontaneous generation, but were derived from already existing living things?

By the early 1900's there was a curious situation where all scientists accepted Pasteur had proven spontaneous generation could not occur via natural processes in the present day world, but Darwin's theory of evolution, with its implicit spontaneous generation by natural processes was also becoming more popular. For many people a Divine Creator could be called on to explain the origin of the first living cell from non-living matter, but they then believed Darwin's evolutionary processes could explain how different life forms have arisen from the first.

However, in 1917 the Bolshevik Revolution in Russia established a Communist state whose official religion was Atheism, a belief that excludes the even possibility of a Creator God kick-starting life. Therefore, the origin of life must be explained by natural processes alone. For an Atheist, all that was available to make life in the beginning was Matter, Time and Energy.

In 1924 a leading atheistic scientist of Soviet Russia, Alexander Oparin (1894-1980) suggested that organic (carbon containing) molecules existed on earth before life arose and these somehow joined together to form living cells. Oparin thus claimed life originated by a new version of Spontaneous Generation due solely to the Natural Properties of the material world. To avoid Pasteur's conclusion that Spontaneous Generation is impossible under present circumstances, Oparin suggested the world's environment was somehow different in the past.

Oparin's idea of organic molecules forming spontaneously, and then joining together to eventually form living things, was taken up by an American chemist Harold Urey. In the present earth organic molecules do not spontaneously form, mainly because of the presence of oxygen, so Urey proposed that the earth originally had an atmosphere of methane, ammonia and hydrogen, without oxygen. Urey's idea was known as the "primitive earth hypothesis." He suggested lightening could have provided the energy to make simple molecules react with one another to form more complex molecules.

In 1953 Stanley Miller (1930-), who was working in Urey's laboratory, set up an experiment to test the theory that the Natural Properties of simple compounds such as methane and ammonia, reacting under the conditions proposed in Urey's "primitive earth", would lead to the formation of biological molecules. He set up the apparatus shown in the diagram

The methods and results of Miller's experiment were published in the journal Science vol 117, pp528-529, 15 May 1953. Miller simulated Urey's "primitive atmosphere" by placing gases, such as methane, hydrogen and ammonia, along with water, in his apparatus. An electric spark was used to simulate lightening water was heated to produce water vapour. No oxygen was allowed to enter the apparatus. After one week the original clear solution had turned red. Chemical testing showed amino acids similar to those found in living cellswere now present in the solution.

Since amino acids are linked together to form proteins in living organisms, proponents of the new evolutionary version of Spontaneous Generation argued Miller's amino acid experiment represented the first step to forming life by natural processes.

Following this would be a series of hypothetical steps where proteins would be combined to form living cells. This idea can be summarized as:

As a result, many people concluded that Miller's experiment had conclusively established that life could have evolved itself by processes which involved only the Natural Properties of the earth and sun. No outside information from a Creator was needed.

This belief is expressed in a summary of Miller's experiment in a 1990s High School Biology textbook:

"Miller sterilised the equipment to kill all micro-organisms, excluded all traces of oxygen, and simulated lightning by generating sparks between tungsten electrodes. Incredibly, within a week the raw materials of life assembled themselves like enchanted building blocks, creating the ordered structures of amino acids - the building blocks of proteins - where before there had been only chaos."
(Reference: Levine & Miller, Biology, 1991, p270)

Was Miller's amino acid experiment the formula for Spontaneous Generation of life by natural processes alone?

We will take a closer look at his results and compare them with the molecules found in living cells in Chapter 3.

SUMMARY OF CHAPTER 2

Louis Pasteur had proven that living things did not arise from non-living matter in the present world, but the theory of evolution claims that living things must have somehow arisen spontaneously by natural processes sometime in the past.

Alexander Oparin suggested that the original earth had a different atmosphere - one that would facilitate the spontaneous generation of organic molecules, which could later come together to form living cells.

Using natural processes Stanley Miller made amino acids, essential building blocks of life, from water vapour and simple gases exposed to an electrical spark. He and his followers claimed this proved that molecules found in living cells could have been spontaneously generated by natural processes alone, and so life could have started on earth without any need for a Creator.