What causes events on Earth's surface such as earthquakes or mountain building? Objective Students will be able to explain how scientific theories develop, specifically the theory of plate tectonics. Background In science, theories are proposed explanations put forward by scientists that have been tested and have evidence to support them. Evidence is used to help support or disprove a theory. Geologists and paleontologists develop theories (e.g., plate tectonics) using evidence they find in the field (e.g., fossils). The plate tectonics theory states that Earth’s crust is broken into plates th Duration: 30 Minutes.