The Lost Worlds of Planet Earth Ortelius hypothesized the idea that land masses may have been connected in the past, Alfred Wegener who hypothesized the idea of a super-continent Pangaea and continental drift despite the prevailing idea of flooded land-bridges at the time, and Bruce C. Heezen and Marie Tharp who discovered the Mid-Atlantic Ridge that supported the theory of plate tectonics. Tyson describes how the landmasses of the earth lay atop the mantle, which moves due to the motion and heat of the earth's outer and inner core. Tyson moves on to explain the asteroid impact that initiated the Cretaceous–Paleogene extinction event, leaving small mammals
The Continent Makers story set on Earth in terms of chronology. P. Schuyler Miller, in a review of the collection, observed that the reader "may feel cheated to find that the title story, worth about one quarter of the book, takes place back on Earth," though finding its "various aliens" and "grand climax" worthy of comment. The Continent Makers The Continent Makers is a science fiction novella by American writers L. Sprague de Camp, part of his "Viagens Interplanetarias" series. It was first published in the magazine "Thrilling Wonder Stories" in the issue for April, 1951. It first appeared in book form in