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
Challenge of the Super Friends DVDs). Eleven heroes make up the Super Friends/Justice League of America. They are: Thirteen villains comprise the Legion of Doom during the "Challenge of the Super Friends" season. They are: Despite the claim in the program's title sequence that the Legion's members hail from "remote galaxies", only Brainiac and Sinestro are extraterrestrials; the remaining members are all natives of Earth (Even though Bizarro called Bizarro World home he was created by Lex Luthor via duplicator ray on Earth technically making him a 'native' of Earth). Solomon Grundy is a zombie, an animated dead person, as the episode Monolith of Evil