Origin of Life

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Example #4

Observation: Since there were no refrigerators, the mandatory, daily trip to the butcher shop, especially in summer, meant battling the flies around the carcasses. Typically, carcasses were “hung by their heels,” and customers selected which chunk the butcher would carve off for them.

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Example #4

Conclusion: Obviously, the rotting meat that had been hanging in the sun all day was the source of the flies.

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Abiogenesis Recipes

Recipe for bees:

Kill a young bull, and bury it in an upright position so that its horns protrude from the ground. After a month, a swarm of bees will fly out of the corpse.

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Abiogenesis Recipes

Recipe for mice:

Place a dirty shirt or some rags in an open pot or barrel containing a few grains of wheat or some wheat bran, and in 21 days, mice will appear. There will be adult males and females present, and they will be capable of mating and reproducing more mice.

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Disproving Spontaneous Generation

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Francesco Redi (1668)

In 1668, Francesco Redi, an Italian physician, did an experiment with flies and wide-mouth jars containing meat

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Redi’s Experiment

Redi used open & closed flasks which contained meat.

His hypothesis was that rotten meat does not turn into flies.

He observed these flasks to see in which one(s) maggots would develop.

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Redi’s Findings

He found that if a flask was closed with a lid so adult flies could not get in, no maggots developed on the rotting meat within.

In a flask without a lid, maggots soon were seen in the meat because adult flies had laid eggs and more adult flies soon appeared.

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Redi’s (1626-1697) Experiments

Evidence against spontaneous generation: 1. Unsealed – maggots on meat 2. Sealed – no maggots on meat 3. Gauze – few maggots on gauze, none on meat

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Results of Redi’s Experiments

The results of this experiment disproved the idea of spontaneous generation for larger organisms, but people still thought microscopic organisms like algae or bacteria could arise that way.

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