Portal:Mesozoic

Topics Culture Geography Health History Mathematics Nature People Philosophy Religion Society Technology The Mesozoic Portal Template:/box-header The Mesozoic era /mɛzoʊˈzoʊɪk/ is an interval of geological time from about 252 to 66 million years ago. It is also called the age of reptiles, a phrase introduced by the 19th century paleontologist Gideon Mantell who viewed it as dominated by reptiles such as Iguanadon, Megalosaurus, Plesiosaurus and what are now called Pseudosuchia. Mesozoic means "middle life", deriving from the Greek prefix meso-/μεσο- for "between" and zōon/ζῷον meaning "animal" or "living being". It is one of three geologic eras of the Phanerozoic Eon, preceded by the Paleozoic ("ancient life") and succeeded by the Cenozoic ("new life"). The era is subdivided into three major periods: the Triassic, Jurassic, and Cretaceous, which are further subdivided into a number of epochs and stages. The era began in the wake of the Permian–Triassic extinction event, the largest well-documented mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction which is known for having killed off non-avian dinosaurs, as well as other plant and animal species. The Mesozoic was a time of significant tectonic, climate and evolutionary activity. The era witnessed the gradual rifting of the supercontinent Pangaea into separate landmasses that would eventually move into their current positions. The climate of the Mesozoic was varied, alternating between warming and cooling periods. Overall, however, the Earth was hotter than it is today. Non-avian dinosaurs appeared in the Late Triassic and became the dominant terrestrial vertebrates early in the Jurassic, occupying this position for about 135 million years until their demise at the end of the Cretaceous. Birds first appeared in the Jurassic, having evolved from a branch of theropod dinosaurs. The first mammals also appeared during the Mesozoic, but would remain small—less than 15 kg (33 lb)—until the Cenozoic. Template:/box-footer Artist's restoration of Sinosauropteryx. Sinosauropteryx is a compsognathid dinosaur. Described in 1996, it was the first dinosaur taxon outside of Avialae (birds and their immediate relatives) to be found with evidence of feathers. It was covered with a coat of very simple filament-like feathers. Structures that indicate colouration have also been preserved for some of the feathers, which makes Sinosauropteryx the first non-avialian dinosaurs where colouration has been determined. Colouration includes a reddish and light banded tail. Sinosauropteryx was a small theropod with an unusually long tail and short arms. The longest known specimen reaches up to 1.07 m (3.5 ft) in length, with an estimated weight of 0.55 kg (1.2 lb). It was a close relative of the similar but older genus Compsognathus, both genera belonging to the family Compsognathidae. Only one species of Sinosauropteryx has been named: S. prima, meaning "first" in reference to its status as the first feathered non-avialian dinosaur species discovered. Sinosauropteryx lived in what is now northeastern China during the early Cretaceous period. It was among the first dinosaurs discovered from the Yixian Formation in Liaoning Province, and was a member of Jehol Biota. Well-preserved fossils of this species illustrate many aspects of their biology, such as their diet and reproduction. (see more...) The Jeita Grotto is a system of two separate, but interconnected, karstic caves in Jurassic limestone spanning an overall length of nearly 9 kilometres (5.6 mi). The caves are situated in the Nahr al-Kalb valley within the locality of Jeita, 18 kilometres (11 mi) north of the Lebanese capital Beirut. Though inhabited in prehistoric times, the lower cave was not rediscovered until 1836 by Reverend William Thomson; it can only be visited by boat since it channels an underground river that provides fresh drinking water to more than a million Lebanese. In 1958, Lebanese speleologists discovered the upper galleries 60 metres (200 ft) above the lower cave which have been accommodated with an access tunnel and a series of walkways to enable tourists safe access without disturbing the natural landscape. The upper galleries house the world's largest known stalactite. The galleries are composed of a series of chambers the largest of which peaks at a height of 120 metres (390 ft). Aside from being a Lebanese national symbol and a top tourist destination, the Jeita grotto plays an important social, economic and cultural role and is a finalist in the New 7 Wonders of Nature competition, and as of 7:44 pm GMT the provisional New7Wonders of Nature based on the first count of vote results on 11/11/11 Jeita was one of the top 14 Finalists in the New7Wonders of Nature. (see more...) Cycadeoidea marylandica fossil specimens in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA. ... that it is all but impossible to match up species known by leaves with those known by trunks in the prehistoric cycad-like genus Cycadeoidea? ... that the stems in the pseudo-trunk of the extinct fern Tempskya decayed as the plant matured, leaving a layer of adventitious roots behind? ... that the flat-headed crocodilian relative Aegisuchus had a circular projection on top of its skull that may have served as an eyespot in mating displays? ... that findings of Cylindroteuthis and other belemnites in Greenland suggest that an early form of the Gulf Stream existed as early as the Valanginian (Early Cretaceous)? ... that the hypercarnivorous crocodyliform Stratiotosuchus (pictured) from the Late Cretaceous of Brazil occupied the niche of top predator in the absence of theropod dinosaurs? Template:/box-header Geochronology - Triassic (Early - Middle - Late) - Jurassic (Early - Middle - Late) - Cretaceous (Early - Late) Mesozoic landmasses - Pangaea - Gondwana - Laurasia - Africa - North America - South America - Antarctica - Asia - Australia - Europe - Appalachia - Laramidia Major Mesozoic events - Mesozoic Marine Revolution - Carnian Pluvial Event - Triassic-Jurassic extinction event - Toarcian turnover - Cretaceous Terrestrial Revolution - Western Interior Seaway anoxia - Chicxulub impact - Cretaceous-Paleogene extinction event Triassic appearances - Belemnites - Crickets - Dinosaurs - Earwigs - Ichthyosauromorphs - Pseudosuchians - Pterosaurs - Sauropterygians - Testudinates Jurassic appearances - Ammonitids - Ankylosaurs - Avialans - Caecilians - Carnosaurs - Caudates - Ceratopsians - Ceratosaurs - Coelurosaurs - Cryptodires - Dromaeosaurids - Equisetum - Frogs - Horse-flies - Lepidopterans - Lizards - Mammals - Ornithopods - Pterodactyloids - Sauropods - Snakeflies - Stegosaurs - Tyrannosauroids Cretaceous appearances - Abalones - Anglerfishes - Ants - Bees - Catfishes - Copepods - Cormorants - Crocodilians - Flowering plants - Fowls - Geckos - Hadrosauroids - Hermit crabs - Lobsters - Mosasaurs - Ornithomimosaurs - Oviraptorosaurs - Pachycephalosaurs - Requiem sharks - Sea turtles - Snakes - Squids - Stingrays - Therizinosaurs Fossil sites - Berlin–Ichthyosaur State Park - Petrified Forest National Park - Dinosaur National Monument - Dinosaur Valley State Park Stratigraphic units - Chinle Formation - Elliot Formation - Ischigualasto Formation - Kimmeridge Clay - Morrison Formation - Oxford Clay Formation - Solnhofen lithographic limestone - Tendaguru Formation - Crato Formation - Dinosaur Park Formation - Djadochta Formation - Hell Creek Formation - Niobrara Formation - Two Medicine Formation - Wessex Formation - Yixian Formation History - History of paleontology - Timeline of paleontology - Timeline of ankylosaur research - Timeline of ceratopsian research - Timeline of ceratosaur research - Timeline of dromaeosaurid research - Timeline of hadrosaur research - Timeline of ichthyosaur research - Timeline of plesiosaur research - Timeline of stegosaur research - Timeline of tyrannosaur research Researchers - William Buckland - Edward Drinker Cope - Jack Horner - Othniel Charles Marsh - Gideon Algernon Mantell - John Ostrom - Sir Richard Owen - Harry Govier Seeley - Samuel Wendell Williston Culture - Treatise on Invertebrate Paleontology - Vertebrate Paleontology - Walking with Dinosaurs - Jurassic Park Template:/box-footer Template:/box-header Featured Mesozoic articles - Bone Sharps, Cowboys, and Thunder Lizards - Bone Wars - Edward Drinker Cope - Geology of the Capitol Reef area - Geology of the Death Valley area -Geology of the Grand Canyon area - Geology of the Zion and Kolob canyons area Good Mesozoic articles - Chitinozoan - Coal ball - Dimetrodon - History of paleontology - Evolutionary history of life - Ornatifilum - Opabinia - Paleontology- Schinderhannes - Small shelly fauna - Temnospondyli - Tiktaalik - Waptia Template:/box-footer ▼ Mesozoic ► Triassic ► Jurassic ► Cretaceous ► Mesozoic life Here are some tasks awaiting attention: Stubs : Mesozoic stubs, Triassic stubs, Jurassic stubs, Cretaceous stubs Current Paleozoic FACs - none currently Template:/box-footer Time Earth sciences Paleontology Extinct and Endangered Species Paleozoic Triassic Jurassic Cretaceous Cenozoic What are portals? List of portals Featured portals