what are 3 examples that make scientists believe that the continents once fit together?
http://www.google.com/search?q=gaia&oq=gaia&aqs=chrome..69i57.2890j0j7&sourceid=chrome&es_sm=119&ie=UTF-8#q=pangea
Read several of these and look carefully at the images.
The similarities of the outlines of the continents
The similarities of some of the life forms of the continents
http://en.wikipedia.org/wiki/Continental_drift
Scientists believe that the continents once fit together based on several lines of evidence. Here are three examples:
1. Continental Fit: The first piece of evidence is the fit of the continental shapes. If you look at the globe, you'll notice that the eastern coastline of South America and the western coastline of Africa fit together like puzzle pieces. This is not a perfect match due to modifications over time, but their shapes are complementary, suggesting they were once connected.
2. Rock and Fossil Correlations: Another key evidence is the correlation of rock types and fossils across continents. For instance, similar rock formations and fossil records of plants and animals can be found on both sides of the Atlantic Ocean, such as the Appalachian Mountains in North America aligning with the Caledonian Mountains in Europe.
3. Paleomagnetism: Paleomagnetism is the study of the Earth's magnetic field recorded in rocks. Through paleomagnetic studies, scientists have discovered that certain rock formations on different continents have polarities that match, indicating they were once adjacent. This supports the notion of continents moving apart from a common position.
To further explore this topic, you can look into scientific papers and studies on continental drift, plate tectonics, or the work of Alfred Wegener, who proposed the theory of continental drift in the early 20th century.