1) In the early 20th century, Alfred Wegener proposed the theory of continental drift, which suggested that the continents were once joined together in a supercontinent called Pangaea before drifting apart over millions of years. 2) Wegener provided evidence from geology, fossils, and the matching coastlines of separated continents to support his theory. This included matching mountain ranges, glacial patterns that indicated different climates, and fossils found across continents. 3) While controversial at first, Wegener's theory is now widely accepted by geologists, though some dispute parts of his evidence and mechanisms. The drifting of continents explains geological features like connected mountain ranges and provides a framework for understanding historic climates and distributions of species