Spontaneous Generation

Beginning of the spontaneous generation

400

The birth of the Spontaneous generation started when Aristotle argued that spontaneous generation was on of the four means of reproduction in 400 BC, with The History of Animals. He explained that how there were animals that came from parent animals and others that grew spontaneously from inanimate objects

THe first time that the Medival Church accepts spontaneous generation

Oct 10, 1225

St. Thomas Aquinas announces that the exact machine of spontaneous generation is that " it was all done by angels acting through the agency of the sun"

First assault on the concept

Aug 11, 1668

An Itialian physician, Francesco Redi conducted an experiment to test spontaneous generation. He placed meat in various flasks, some open to air, some with a gauze and some completely sealed. He found that only the ones that allowed air to get to the meat had maggots growing in the meat. He believed he disproved spontaneous generation; however, the general public still believed in the theory.

Microscope

Jan 31, 1680

During the later 1600's, smaller microorganisms were found because of the development of the microscope. These microorganisms were never thought to exist before, but they were associated with things like spoiled broth or meat. Spontaneous generation was used as the explanation for these organism's sources because they seemed to come from nowhere.

Defence of the spontaneous generation

Jul 14, 1745

In 1745, John Needham, an English clergyman, attempted to prove once an for all the validity of spontaneous generation. Everyone knew that boiling killed microorganisms, so he proposed to test whether or not microorganisms appeared spontaneously after boiling. He boiled chicken broth, put it into a flask, sealed it, and waited. Microorganisms grew and he thought he had won the battle in support of spontaneous generation.

the rest of Spontaneous generation

Oct 30, 1859

The French Academy of Sciences sponsored a contest for the best experiment either proving or disproving spontaneous generation. He boiled meat broth in a flask, heated the neck of the flask in a flame until it became pliable, and bent it into the shape of an S. Air could enter the flask, but airborne microorganisms could not - As Pasteur had expected, no microorganism grew and the rest is history.

Biogenesis and Abiogenesis lecture

Nov 2, 1870

Thomas H. Huxley gives his "Biogenesis and Abiogenesis" lecture. The speech offered powerful support for Pasteur's claim to have experimentally disproved spontaneous generation.