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Redi's Experiment
Experiment in which meat was put in jars with different seals to disprove the idea that maggots and flies would surge from the rotting meat. It was found that in tightly sealed jars, no flies would show up. Even with this experiment, spontaneous generation was still widely believed. Done by Francesco Redi. -
Needham's Rebuttal
An experiment to refute Redis, made by John Needham. In this, broth in a flask was brought to it's boiling point briefly to kill microorganisms, sealed, waited for it to cool down, and then searched for microorganisms. The experiment found microorganisms in the broth, and thus it was concluded that spontaneous generation was real. -
Criticisms towards Needham
Lazzaro Spallanzani performed the same experiment as Needham, but sealed the flask before boiling and let the broth boil for much longer to truly kill all the microorganisms. He then saw that microorganisms only appeared in the broth after air exposure, so the living microorganisms must be from air contamination, and thus he concluded that spontaneous generation was a farce. However, people attributed this to the fact that spontanous generation had to occur with the life force of air. -
Pasteur Sweep
Louis Pasteur performed an experiment to finally disprove spontaneous generation similar in nature to Spallanzani's, but instead of a regular flask, he used a swan-neck flask that allowed air to flow in without the broth being contaminated. The results were that no microorganisms were found in the broth. After this, he tilted the flask to allow easier passage for microorganisms, and soon enough, they found their way into the broth. With this, spontaneous generation was finally disproven.