lazzaro spallanzani came up with the theory of spontaneous generation.
lazzaro spallanzani came up with the theory of spontaneous generation.
who came up with the theory of spontaneous generation?
lazzaro spallanzani
in his biological works, the natural philosopher aristotle theorized extensively the reproduction of various animals, whether by sexual, parthenogenetic, or spontaneous generation. in accordance with his fundamental theory of hylomorphism, which held that every physical entity was a compound of matter and form, aristotle's basic theory of sexual reproduction contended that the male's seed imposed form, the set of characteristics passed down to offspring on the "matter" (menstrual blood) supplied by the female. thus female matter is the material cause of generation—it supplies the matter that will constitute the offspring—while the male semen is the efficient cause, the factor that instigates and delineates the thing's existence. yet, as proposed in the "history of animals", many creatures form not through sexual processes but by spontaneous generation:
spontaneous generation
before the 1870s, when pasteur published his work on this theory, it was believed that microorganisms and even some small animals such as frogs would spontaneously appear, which was coined as spontaneous generation. spontaneous generation was the explained theory that when elements of the earth such as clay or mud would mix with water and sunlight in certain amounts, creatures would just appear out of that concoction. a common way that this idea was "proven" over and over again was by taking a piece of raw meat and placing it in open air, which would almost always produce maggots. this idea was accepted and believe to be true before louis pasteur shook the earth with his new ideas that organisms actually came from traceable beginnings. pasteur demonstrated that fermentation is caused by the growth of microorganisms, and the emergent growth of bacteria in nutrient broths is due to biogenesis rather than spontaneous generation. he exposed boiled broths to air in vessels that contained a filter to prevent all particles from passing through to the growth medium. yet, when the vessels were open to the air surrounding it, the organisms appeared. it could be concluded that spontaneous generation could be disproven. the organisms did not just appear but were coming from the air, yet we were not able to see them at such a small level. his famous experiment was used with a curved neck placed on top of a beaker. this curved neck was the key to proving his findings because it showed that the germs and microbes had to fall into the broth inside. the curved neck did not allow this to happen.
fermentation theory