Spontaneous generation theory

We all learned too well how Louis Pasteur, after a series of remarkable experiments, smashed the spontaneous generation theory. He put forth, however, an authoritative ne pas possible dictum that brought no good for a long time. In fact, it took many decades to overcome his paralyzing testimonial, until Haldane, Oparin and, years later, Stanley Miller (1953) started to probe a fascinating subject anew. 

During the 1800s the theory of spontaneous generation was raging in the scientific circles. Pasteur s work proved that food and other organic matter does not spontaneously generate microbes and settled the controversy. 

Theory of Spontaneous Generation Inheritance of Acquired Characteristics The Blending Hypothesis... 

The key to persuading people was the portrayal of the cells as simple. One of the chief advocates of the theory of spontaneous generation during the middle of the nineteenth century was Ernst Haeckel, a great admirer of Darwin and an eager popularizer of Darwin s theory. From the limited view of cells that microscopes provided, Haeckel believed that a cell was a simple little lump of albuminous combination of carbon, 7 not much different from a piece of microscopic Jell-O. So it seemed to Haeckel that such simple life, with no internal organs, could be produced easily from inanimate material. Now, of course, we know better. 

Development of the microscope by Anton van Leeuwenhoek (1673) and others, enabled man to see a new world of microcreatures. including bacteria, yeasts, molds, blood cells, and spermatozoa, and microstructures such as muscle fibers and plant and seed tissues. This added credibility to later claims by Louis Pasteur and Robert Koch that microorganisms can spoil foods and cause disease at a time when many influential learned men still clung to theories of spontaneous generation of life. 

Generation Spontaneous generation of gas bubbles within a homogeneous liquid is theoretically impossible (Bikerman, Foams Theory and Industrial Applications, Reinhold, New York, 1953, p. 10). The appearance of a bubble requires a gas nucleus as a void in the liquid. The nucleus may be in the form of a small bubble or of a solid carrying adsorbed gas, examples of the latter being dust particles, boiling chips, and a solid wall. A void can result from cavitation, mechanically or acoustically induced. Blander and Katz [AlChE 21, 833 (1975)] have thoroughly reviewed bubble nucleation in liquids. 

Although Redi, Pasteur, and other scientists thoroughly disproved the theory of spontaneous generation as an explanation for the origin of present-day life on whatever scale, they raised a new question If organisms can arise only from other organisms, how then did the first organism arise ... 

The other great pillar in the edifice of artificial life was Aristotle s theory of sexual, as opposed to spontaneous, generation. Aristotle, as we have said, believed that every material substance must consist of matter and form. In the case of sexual generation, however, we encounter two substances that are at the extreme ends of the scale. Sperm is almost pure form, and menstrual blood is almost pure matter. The sperm in effect acts as the form to the matter supplied by the menstrual blood in order to produce a living being. When male semen enters the womb, a conflict arises between the sperm and the menstrual blood. As Aristotle says in The Generation of Animals (766b 15—18) ... 

After studying the problem for six years, in 1861 Pasteur reported that fermentation and putrefaction were both caused by living organisms. This discovery spelled the doom of the theory of spontaneous generation, a sacrosanct... 

Spontaneous generation The theory that living organisms can arise from non-living things. 

The experimental results obtained by independent groups of researchers in the different laboratories discussed above confirm one of the main postulates of the theory of the abyssal abiogenic origin of petroleum complex hydrocarbon systems could be spontaneously generated deeply in the Earth under the upper mantle conditions. 

Remarkably, we shall find that the above phenomenon allows the construction of a gauge theory in which the underlying S3unmetry is spontaneously broken, and as a result masses for the W s as well as for the leptons are spontaneously generated . 

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