Whenever new discoveries force scientists to reconsider their hypotheses, theories and data, they do just that. This is why people think of science as a collection of concepts that are always being revised.
This holds true for the basic building block concepts within science as well. The cell is a perfect example of this: in the mid-1600s, Robert Hooke used one of the very first microscopes to examine thin slices of cork. When he saw that the cork plant was made up of tiny box-shaped pieces, he gave science the concept of the cell. For 100 years, people thought of the cell as the smallest thing inside all living creatures. But then, in 1781, Felice Fontana spotted something even smaller inside the cells from an eel: the nucleolus. This discovery made people rethink the idea that cells were the tiniest things inside living creatures. Clearly, there were even smaller things inside cells.
Since Fontana’s time, scientists have refined, revised, and rewritten their view of the cell thousands of times in order to match up with every piece of new data. This same process has happened with the scientific view of geological processes including plate tectonics and the seismic wave energy generated during earthquakes.
Review your Reading this week focusing on plate tectonics.
Learn more about Alfred Wegener here:
http://pubs.usgs.gov/gip/dynamic/wegener.html
http://scign.jpl.nasa.gov/learn/plate2.htm
Shifting Continents: A Case Study in Scientific Revision
Using what you learned about plate tectonics, Alfred Wegener, and the basics of scientific investigation from the previous units discuss the following:
- Did Wegener reveal his theory of continental drift too soon? For the sake of scientific investigation, how is revealing an explanation for a process early both risky and sometimes necessary?
- Apart from lacking an explanation for how the continents could move across the surface of the Earth, Wegener’s research was met by skepticism for other reasons. How can a scientist overcome skepticism? What features of the scientific method can help prevent a scientist from being labeled a “crackpot?”
- If Alfred Wegener were alive today, and had access to the technology and data that exists today, share a form of evidence that he could have added to his hypothesis or would have changed his hypothesis. Try to share a different form of evidence from those shared by your classmates and/or add to their posts by describing how the evidence is collected, how the technology works to collect the data, or how this technology/evidence has been used in other applications.
