How science changes


Published on

Published in: Technology, Education
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

How science changes

  1. 1. How Science Changes<br />Leslie Prohaska<br />Florida State University <br />SCE5943 <br />Field Lab Internship<br />Dr. Alejandro Gallard <br />October 19, 2009<br />
  2. 2. The story of Pangea<br />Remember how the theory of plate tectonics developed<br />Alfred Wegener proposed his idea of continental drift in his 1915 book, The Origin of Continents and Oceans<br />His evidence included fossils of the same lizard and same plant being found on the eastern side of South America and western side of Africa<br />This was not enough though…<br />
  3. 3. More evidence needed<br />When technology improved after World War II, scientists were able to map the floor of the ocean<br />Magnetic stripes were found on the sea floor which proved that the sea floor was spreading<br />The theory of plate tectonics was finally accepted in the 1960’s because of this evidence<br />
  4. 4. This is how science works<br /><ul><li>Scientists continue to experiment, to make observations, take data, and collect evidence
  5. 5. As technology improves, there are new ways to experiment and to make these observations
  6. 6. If this new information does not fit with the old explanations or, then scientists will make new theories to explain their findings
  7. 7. Yes, scientists can change their minds!</li></li></ul><li>Science is about improving our understanding<br /><ul><li>The history of science reveals both evolutionary and revolutionary changes. With new evidence and interpretation, old ideas are replaced or supplemented by newer ones. (NSTA Board of Directors, 2000)
  8. 8. Progress in science consists of the development of better explanations for the causes of natural phenomena. (Teaching about Evolution and the Nature of Science, 1998, p.42)
  9. 9. Explanations that we discuss today may continue to change.</li></li></ul><li>Other examples…of the nature of science…that we have Discussedbefore<br />
  10. 10. The Atomic Theory<br /><ul><li>Democritus, ‘atomos’
  11. 11. Dalton, 1808, all matter is made of atoms
  12. 12. JJ Thomson, 1897, plum pudding model
  13. 13. Rutherford, 1909, gold foil experiment, most of the atom is open, empty space
  14. 14. Bohr, 1913, orbits and energy levels
  15. 15. Modern atomic model, wave mechanics model, 1926</li></li></ul><li>The Cell Theory<br /><ul><li>Robert Hooke, 1665, first saw cells in microscope and thought they looked like little rooms he called cells
  16. 16. Matthias Schleiden –1837, all plants are composed of cells
  17. 17. Theodore Schwann – 1839, all animals are composed of cells
  18. 18. Modern Cell Theory – 1858, 1) cells are the basic unit of life, 2) all organisms are composed of one or more cells, 3) all cells arise from preexisting cells</li></li></ul><li>History of classification<br /><ul><li>Aristotle – 350 B.C. 2 large groups, plants and animals
  19. 19. Carolus Linnaeus – 1753, kept two kingdoms but broke them into smaller groups and had everyone use Latin
  20. 20. Five kingdom system, 1959, Animal, Plant, Fungi, Protists, Moneran, Whittaker
  21. 21. Six kingdom system proposed/Three domains???? Still not resolved</li></li></ul><li>Things continue to change<br /><ul><li>As scientific knowledge evolves, major disagreements are eventually resolved… (National Science Education Standards, 1996, p. 171)
  22. 22. This is part of scientific inquiry</li></li></ul><li>References<br />American Association for the Advancement of Science. (1990). Chapter 1: The Nature of Science. Retrieved October 17, 2009, from<br />National Science Education Standards observe, interact, change, learn. (1996). Washington, DC: National Academy Press.<br />NSTA Board of Directors. (2000, July). Nature of Science Position Statement - NSTA Position Statements. Retrieved October 17, 2009, from<br />Teaching about evolution and the nature of science. (1998). Washington, DC: National Academy Press.<br />