Early evidence showing striking similarities between regions on opposite sides of vast oceans suggested that in Earth's distant past what are now separate continents may once have been connected. However, this evidence said nothing about how the continents could have moved to their present positions. This video segment from adapted A Science Odyssey describes the search for evidence of a mechanism and forces that could propel tectonic plates across Earth's surface.
This video is available in both English and Spanish audio, along with corresponding closed captions.
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