1. Development of Scientific Process Abiogenisis to Biogenisis

2. Science vs the Churches The Gauntlet 1870

3. Two Factors That Helped The Development Of Science: 1. Development of the microscope. 2. Debate about the nature of life vitalism or mechanism.

4. Philosophies of VITALISM AND MECHANISM Thoughts from the 17 th and 18 th Centuries Vitalism Living organisms have special properties that allow them to operate independently of physical laws. Used to explains observations like: maggots appearing on rotting meat; fungi growing on wood; rodents running out of piles of vegetation...etc.

5. Philosophy of Vitalism AKA spontaneous generation or abiogenesis. New life occurs when nonliving materials received a life force from living or formerly living material

6. The opposing philosophy Mechanism Living organisms are part of the physical world and they operate according to physical laws. Life is determined by how an organism is put together and the processes that occur in it. AKA Biogenesis

7. "Life begets life” Biogensisis All living organisms give rise to other living organisms to form a new organism of the same type. Since living organisms obey regular physical laws, then the proper compounds and conditions are required to synthesize organic molecules.

8. Abiogenesis vs Biogenesis and The Development Of The Scientific Method A result of the battle between the philosophies of vitalism and mechanism was that the arguments increasingly relied on philosophical arguments that ultimately led to the development of the Scientific Method

9. Spontaneous Generation or Abiogenesis Since Aristotle (4th Century BC), it was believed that non-living objects could give rise to living organisms. Based on observations like: Nile flooding Moldy grain and mice Sewers and rats

10. People believed that you could write a recipe for life 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.

11. How to Create Mice Jan Baptista van Helmont’s 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.

12. Life Force Could be transferred to objects Could generate new forms of life Most common observations were from meat, broth etc. that people had in their homes – often associated with flies.

13. Biogenesis Until the 19 th century,(200 years ago) Spontaneous Generation was accepted Development of ideas and technologies lead scientists to believe in the theory of Biogenesis the process of life forms producing other life forms, e.g. a spider lays eggs, which develop into spiders.

14. Progression of Ideas and Innovations 1546 - - Hieronymus Fracastorius (France) Introduced idea of contagious infection

15. Microscopes 1590 - - Hans and Zacharias Janssen made the first compound microscope. 1660 - - Robert Hooke First observed cells (cork) Used a compound microscope that could magnify 30 - 100 X.

16. Animalcules 1676 - - Anton van Leeuwenhoek developed a microscope that could magnify over 200 X. He was the first to observe bacteria, protists, and other micro organisms. He called them animalcules. He was considered crazy by fellow citizens

17. Maxine Kumin, The Microscope [ the full text of from Kumin’s 1963 children’s book ]: Anton Leeuwenhoek was Dutch He sold pincushions, cloth, and such. The waiting townsfolk fumed and fussed As Anton’s drygoods gathered dust. He worked, instead of tending store, At grinding special lenses for A microscope. Some of the things He looked at were: mosquitoes’ wings the hairs of sheep, the legs of lice, the skin of people, dogs, and mice; ox eyes, spiders’ spinning gear, fishes’ scales, a little smear of his own blood, and best of all, the unknown, busy, very small bugs that swim and bump and hop inside a simple water drop. Impossible! Most Dutchmen said. This Anton’s crazy in the head. We ought to ship him off to Spain. He says he’s seen a housefly’s brain. He says the water that we drink is full of bugs. He’s mad, we think! They called him dumkopf, which means dope. That’s how we got the microscope.

18. First Scientific Experiment 1688 - - Francesco Redi

19. Redi Experiment Covered jar proved that maggots did not arise spontaneously Critics felt that the flies on the meat with the netting were a result of Abiogenesis Theory still not proven

20. Disproving Redi 1745 - John Needham boiled chicken broth to kill all of the microorganisms. Sealed the container, and waited. Microorganisms grew a few days later, proving to him and several others that spontaneous generation did occur

21. Biogenesis counter experiment Modified Needham's experiment 1750's - Lazzaro Spallanzani chicken broth in flasks were sealed, the air drawn off with a vacuum, then boiled. No microorganisms grew.

22. spontaneous generation supporters argued that spontaneous generation could only occur in the presence of air. John Needham said that Spallanzani destroyed the vital force and that this experiment proved nothing Spallanzani is credited with developing canning – food preservation that changed how the world ate and lived.

23. Handwashing by Physicians 1847 - - Ignaz Semmelweiss - Forced doctors to wash hands He observed the transfer of childbed fever by doctors that did not wash their hands

24. Academy of Science in Paris 1860 To put an end to the debate between the two factions, the Academy offered a prize to the scientist who could finally prove (or disprove) Biogenesis. Louis Pasteur did this. Task Create a timeline (to scale) to show the debate of abiogenesis vs biogenesis.