History of Spontaneous Generation

By yaya121
  • 330 BCE

    ARISTOTLE

    ARISTOTLE
    Aristotle created the theory of spontaneous generation by gathering the work of previous natural philosophers and explanations of the appearance of organisms. This theory lasted for around two millennia. “Vital heat” or pneuma, Aristotle believed that it was the pneuma that contained the non-living material that had power to generate life. This set the foundation for the theory of spontaneous generation.

  • JON BAPTIST VAN HELMONT (1580-1644)

    JON BAPTIST VAN HELMONT (1580-1644)
    A Flemish chemist, physician, and physiologist, Jon was a supporter of spontaneous generation.
    EXPERIMENT: An experiment depicted a willow tree five years after growth. The results showed that although the tree grew in size, the soil did not decrease in matter. Thus, this supported that the extra mass of the tree was being generated from somewhere else.

  • FRANCISCO REDI (1626-1697)

    FRANCISCO REDI (1626-1697)
    An Italian physician named Fransisco Redi was the first person to attack the theory of spontaneous generation.
    EXPERIMENT: A crucial experiment that refuted the theory that maggots arose from decaying meat. Proved maggots came from fly larvae on top of the meat. The way he proved this was by covering the decaying meat, and thus disabling access to the flies, and therefor the meat alone often didn’t result in maggots.

  • MICROSCOPE

    MICROSCOPE
    The invention of the microscope in 1700 was a major turning point. The microscope became a wisely used tool by scientists to see things that otherwise couldn't be seen by the naked eye. It was a key part of spontaneous generation's history, and without it, the incorrect hypothesis might have never been rebuked.

  • JOHN NEEDHAM (1713-1781)

    JOHN NEEDHAM (1713-1781)
    He was another proponent of spontaneous generation, and in order to further advocate for it, he conducted multiple experiments with boiled broths. It was originally believed that if he boiled the substance, all living organisms would be killed. However, after boiling the broth and covering the container, the broth continued clouding, which revealed there was still life in the substance. Therefor proving that spontaneous generation occurred even whilst boiling.

  • LAZZARO SPALLANZANI (1729-1799)

    LAZZARO SPALLANZANI (1729-1799)
    An Italian scientist created another experiment by modifying Needham’s experiment. He believed that after Needham boiled the broth and put it in the jar, it was contaminated. Spallanzani boiled the broth in a sealed container that allowed air to escape which prevented an explosion. He continuously defeated growth in the broth. However, others argued that all he proved was spontaneous generation was unable to occur without air.

  • LOUIS PASTEUR (1822-1895)

    LOUIS PASTEUR (1822-1895)
    Pasteur made an experiment that showed a substance can be absent of all life, however if it is properly protected then no other organisms will be created, even if it were exposed to air.
    EXPERIMENT: Boiled the broth in a flask that would kill all living organisms. Afterwards, he hated the neck of the flask and made it into an ’S’ shape, which didn’t allow organisms to pass not the broth however allowed oxygen to seep in. It was full of life once he tipped the flask.