Spontaneus generation

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Spontaneus Generation Theory.
Spontaneous generation is the hypothesis that some vital force contained in or given to organic matter can create living organisms from inanimate objects. Spontaneousgeneration was a widely held belief throughout the middle ages and into the latter half of the 19th century. In fact, some people still believe in it today. The idea was attractive because it meshednicely with the prevailing religious views of how God created the universe. There was a strong bias to legitimize the idea because this vital force was considered a strong proof of God's presence in theworld. Many recipes and experiments were offered in proof. To create mice, a recipe called for dirty underwear and wheat grain to be mixed in a bucket and left open outside. In 21 days or less, youwould have mice. The real cause may seem obvious from a modern perspective, but to the proponents of this idea, the mice spontaneously arose from the wheat kernels.
Another often-used example was thegeneration of maggots from meat that was left in the open. The failing here was revealed by Francesco Redi in 1668 with a classic experiment. Redi suspected that flies landing on the meat laid eggsthat eventually grew into maggots. To test this idea he devised the experiment shown in the picture below. Here he used three pieces of meat. One piece of meat was placed under a piece of paper. Theflies could not lay eggs onto the meat and no maggots developed. The second piece was left in the open air, resulting in maggots. In the final test, a third piece of meat was overlaid with cheesecloth.The flies were able to lay the eggs into the cheesecloth and when this was removed no maggots developed. However, if the cheesecloth containing the eggs was placed on a fresh piece of meat, maggotsdeveloped, showing it was the eggs that "caused" flies and not spontaneous generation. This helped to end the debate about spontaneous generation for large organisms. However, spontaneous generation...
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