Final answer:
The present shapes of the continents do not fit perfectly into a supercontinent due to continental drift, where the Earth's tectonic plates move and undergo processes like subduction and collision. The evidence for continental drift includes the fit of the continents, matching fossils and rocks, and similarities in climate and species among continents.
Step-by-step explanation:
The present shapes of the continents do not fit perfectly into a supercontinent due to the process of continental drift. Continental drift refers to the movement of the Earth's tectonic plates over time. It was proposed by Alfred Wegener in the early 1900s, who suggested that all continents were once connected in a supercontinent called Pangaea. As the tectonic plates moved, they underwent various processes such as subduction and collision, resulting in the current shape and distribution of the continents.
The evidence for continental drift includes the fit of the continents, where their shapes seem to fit together like puzzle pieces. There are also matching fossil and rock formations on continents that are now separated by oceans, indicating their past connection. Additionally, similarities in climate patterns and biological species among different continents provide support for the idea of a supercontinent.
Overall, the continents' imperfect fit into a supercontinent is a result of the dynamic nature of Earth's tectonic plates and the processes they undergo over millions of years.