What made many scientists think the continents could not have changed position?
Many scientists originally believed that the continents could not have changed position due to a few reasons. One major reason was the concept of "fixism," which held that the Earth's surface was static and unchanging over time. This idea was influenced by religious and philosophical beliefs that suggested the Earth was created in its current form and remained fixed.
Another reason was the observation that the continents seemed to fit together like a puzzle. In the early 20th century, the German meteorologist Alfred Wegener proposed the theory of continental drift, suggesting that the continents were once joined together in a supercontinent called Pangaea and gradually moved apart over millions of years. However, Wegener's theory was initially met with skepticism because there was no known mechanism to explain how continents could move.
Additionally, the prevailing scientific consensus at the time did not support the idea of continents moving. The dominant mindset in geology was focused on geological processes that occurred only within the Earth's crust, such as mountain building and volcanic activity. The idea of large-scale movement of entire land masses was not part of the scientific framework.
It wasn't until the mid-20th century, with advancements in technology and the study of seafloor spreading, that the theory of plate tectonics emerged. This theory provided a mechanism for how continents could move by proposing that the Earth's lithosphere is divided into several large plates that are constantly shifting and interacting with each other. The discovery of magnetic stripes on the ocean floor, as well as the realization that earthquakes and volcanic activity often occur along plate boundaries, provided further evidence for plate tectonics.
In summary, many scientists initially rejected the idea of continents moving due to the concept of fixism, the lack of a known mechanism for continental motion, and the prevailing scientific consensus at the time. However, advancements in technology and the development of plate tectonics theory ultimately led to widespread acceptance of the idea that continents can change position over geological timescales.