. "The history of Spec as a timeline distinct from that of Arel begins roughly 65 million years ago. On Arel, this point in time corresponds with the end of the Mesozoic Era and the dawn of the Cenozoic - the so called Cretaceous-Tertiary (K-T) boundary, although many workers now prefer to divide the Tertiary into the Paleogene(Paleocene-Oligocene) and Neogene(everything else)."@en . . . . . . "Spec: The History of Spec World"@en . . . . . . . . . . . . . . . . . . . . . . . . "The history of Spec as a timeline distinct from that of Arel begins roughly 65 million years ago. On Arel, this point in time corresponds with the end of the Mesozoic Era and the dawn of the Cenozoic - the so called Cretaceous-Tertiary (K-T) boundary, although many workers now prefer to divide the Tertiary into the Paleogene(Paleocene-Oligocene) and Neogene(everything else). Specworld fossils dating from before this boundary most often belong to organisms described in our native timeline\u2019s fossil record, indeed some famous pre-Cenozoic Arel fossil sites such as the Dinosaur National Monument and the Burgess Shales have identical Specworld counterparts that have produced matching specimens. A few Mesozoic Spec fossils (most notably Mirabilotheridium , a monotreme from Cretaceous South America and Lepelara, an early angiosperm) represent new taxa. All these novel finds fit comfortably within the accepted theories of our home-Earth\u2019s Mesozoic history. In all likelihood, these taxa simply represent fossils of creatures that existed on Arel but have yet to be found. Above K-T boundary however, Spec's fossil record diverges radically from the natural history of our home timeline. The most obvious feature is the fact that the dinosaurs did not go extinct along with a host of other organisms that vanished at the K-T boundary on Arel. Secondly, a great variety of animals that appeared in the early Cenozoic of Arel (particularly large mammals) are missing - without a big K-T extinction event to clear out the ecological playing-field these forms never had the opportunity to evolve on Spec."@en . .