Passage
In the autumn of 1911, while browsing the university library at Marburg, Alfred Wegener happened upon a scientific report that listed fossils of identical plants and animals found on opposite sides of the Atlantic. At the time, the prevailing consensus explained these anomalies through hypothetical land bridges that had supposedly sunk into the ocean depths. Wegener, however, found this explanation physically implausible. Inspired by the striking coastline similarity between South America and Africa—a detail he had noted years earlier but dismissed as mere coincidence—he began to synthesize evidence from geology, paleontology, and climatology. When he presented his hypothesis of continental drift at a meeting of the Geological Association in Frankfurt in early 1912, it was met with cold skepticism. Undeterred, Wegener published an expanded treatise three years later, though the lack of a plausible mechanism for how continents actually moved remained a critical flaw. Decades after Wegener's death on a Greenland expedition in 1930, the discovery of mid-ocean ridges and seafloor spreading by Marie Tharp and Bruce Heezen finally provided the missing physical engine, transforming Wegener's rejected hypothesis into the foundation of modern plate tectonics.
Based on the passage, what is the correct chronological order of the following events, from earliest to latest?
- 1Wegener observes the coastline similarities between South America and Africa.
- 2Wegener reads a scientific report detailing identical fossils on opposite sides of the Atlantic.
- 3Wegener presents his continental drift hypothesis to the Geological Association in Frankfurt.
- 4Wegener publishes an expanded treatise on continental drift.
- 5Marie Tharp and Bruce Heezen discover seafloor spreading.