The Triassic (/traɪˈæsɪk/try-ASS-ik; sometimes symbolized 🝈)[8] is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.4 Mya.[9] The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events.[10] The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic.
The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archosaurs, called dinosaurs, first appeared in the Late Triassic but did not become dominant until the succeeding Jurassic Period.[11] Archosaurs that became dominant in this period were primarily pseudosuchians, relatives and ancestors of modern crocodilians, while some archosaurs specialized in flight, the first time among vertebrates, becoming the pterosaurs.
Therapsids, the dominant vertebrates of the preceding Permian period, declined throughout the period. The first true mammals, themselves a specialized subgroup of therapsids, also evolved during this period. The vast supercontinent of Pangaea dominated the globe during the Triassic, but in the following Jurassic period it began to gradually rift into two separate landmasses, Laurasia to the north and Gondwana to the south.
The global climate during the Triassic was mostly hot and dry,[12] with deserts spanning much of Pangaea's interior. However, the climate shifted and became more humid as Pangaea began to drift apart. The end of the period was marked by yet another major mass extinction, the Triassic–Jurassic extinction event, that wiped out many groups, including most pseudosuchians, and allowed dinosaurs to assume dominance in the Jurassic.
^Widmann, Philipp; Bucher, Hugo; Leu, Marc; et al. (2020). "Dynamics of the Largest Carbon Isotope Excursion During the Early Triassic Biotic Recovery". Frontiers in Earth Science. 8 (196): 196. Bibcode:2020FrEaS...8..196W. doi:10.3389/feart.2020.00196.
^McElwain, J. C.; Punyasena, S. W. (2007). "Mass extinction events and the plant fossil record". Trends in Ecology & Evolution. 22 (10): 548–557. doi:10.1016/j.tree.2007.09.003. PMID 17919771.
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Retallack, G. J.; Veevers, J.; Morante, R. (1996). "Global coal gap between Permian–Triassic extinctions and middle Triassic recovery of peat forming plants". GSA Bulletin. 108 (2): 195–207. Bibcode:1996GSAB..108..195R. doi:10.1130/0016-7606(1996)108<0195:GCGBPT>2.3.CO;2. Retrieved 2007-09-29.
^Payne, J. L.; Lehrmann, D. J.; Wei, J.; Orchard, M. J.; Schrag, D. P.; Knoll, A. H. (2004). "Large Perturbations of the Carbon Cycle During Recovery from the End-Permian Extinction". Science. 305 (5683): 506–9. Bibcode:2004Sci...305..506P. doi:10.1126/science.1097023. PMID 15273391. S2CID 35498132.
^Ogg, James G.; Ogg, Gabi M.; Gradstein, Felix M. (2016). "Triassic". A Concise Geologic Time Scale: 2016. Elsevier. pp. 133–149. ISBN 978-0-444-63771-0.
^Hongfu, Yin; Kexin, Zhang; Jinnan, Tong; Zunyi, Yang; Shunbao, Wu (June 2001). "The Global Stratotype Section and Point (GSSP) of the Permian-Triassic Boundary" (PDF). Episodes. 24 (2): 102–114. doi:10.18814/epiiugs/2001/v24i2/004. Retrieved 8 December 2020.
^Hillebrandt, A.v.; Krystyn, L.; Kürschner, W. M.; et al. (September 2013). "The Global Stratotype Sections and Point (GSSP) for the base of the Jurassic System at Kuhjoch (Karwendel Mountains, Northern Calcareous Alps, Tyrol, Austria)". Episodes. 36 (3): 162–198. CiteSeerX 10.1.1.736.9905. doi:10.18814/epiiugs/2013/v36i3/001. S2CID 128552062.
^"International Stratigraphic Chart" (PDF). International Commission on Stratigraphy. June 2023. Retrieved 19 July 2023.
^Sahney, S. & Benton, M.J. (2008). "Recovery from the most profound mass extinction of all time". Proceedings of the Royal Society B: Biological Sciences. 275 (1636): 759–765. doi:10.1098/rspb.2007.1370. PMC 2596898. PMID 18198148.
^Brusatte, S. L.; Benton, M. J.; Ruta, M.; Lloyd, G. T. (2008-09-12). "Superiority, Competition, and Opportunism in the Evolutionary Radiation of Dinosaurs" (PDF). Science. 321 (5895): 1485–1488. Bibcode:2008Sci...321.1485B. doi:10.1126/science.1161833. hdl:20.500.11820/00556baf-6575-44d9-af39-bdd0b072ad2b. PMID 18787166. S2CID 13393888. Archived from the original (PDF) on 2014-06-24. Retrieved 2012-01-14.
^"'Lethally Hot' Earth Was Devoid of Life – Could It Happen Again?". nationalgeographic.com. 19 October 2012. Archived from the original on October 20, 2012.
extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of...
The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between 237 Ma and 201.4 Ma (million...
timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided...
The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and 247.2 Ma (million...
Triassic Attack is a 2010 television film directed by Colin Ferguson and produced by UFO International Productions. It premiered November 27, 2010, on...
IK-thee-ə-TY-tən) is an extinct genus of giant ichthyosaur from the Late Triassic (Rhaetian), known from the Westbury Mudstone Formation in Somerset, England...
geologic period and stratigraphic system that spanned from the end of the Triassic Period 201.4 million years ago (Mya) to the beginning of the Cretaceous...
history, lasting from about 252 to 66 million years ago, comprising the Triassic, Jurassic and Cretaceous Periods. It is characterized by the dominance...
group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact...
(Mya), to the beginning of the Triassic Period 251.902 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic...
Jurassic Period. It has three major epochs: Early Triassic, Middle Triassic, and Late Triassic. The Early Triassic lasted between 252 million to 247 million years...
land animals in the Guadalupian through to the Early Triassic. In the aftermath of the Permian–Triassic extinction event, therapsids declined in relative...
relatives. The oldest true archosaur fossils are known from the Early Triassic period, though the first archosauriforms and archosauromorphs (reptiles...
during the latter part of the Carnian Stage, a subdivision of the late Triassic period, and lasted for perhaps 1–2 million years (around 234–232 million...
Triassic Parq is a musical comedy with music by Marshall Pailet, and lyrics and book by Marshall Pailet, Bryce Norbitz and Steve Wargo. The novel and film...
genus of herbivorous dicynodont therapsids from the late Permian and Early Triassic epochs (around 250 million years ago). It lived in what is now Antarctica...
Shastasauridae is an extinct family of Triassic ichthyosaurs. The family contains the largest known species of ichthyosaurs, which include some of and...
of the "Big Five" extinction events. Triassic–Jurassic extinction event (End Triassic): 201.3 Ma, at the Triassic–Jurassic transition. About 23% of all...
(approximately 260 mya), and extensively diversified after the Permian–Triassic extinction event. Mammals are cynodonts, as are their extinct ancestors...
about 90 million years ago, into the Late Cretaceous. During the Early Triassic epoch, ichthyosaurs and other ichthyosauromorphs evolved from a group of...
Pangea. It began to separate from northern Pangea (Laurasia) during the Triassic, and started to fragment during the Early Jurassic (around 180 million...
the Triassic Period (252 - 201 Ma), though Lucas later designated LVFs for other periods as well. Eight worldwide LVFs are defined for the Triassic. The...
from the Late Triassic. Specimens have been found in the United States, Canada, and China. Shastasaurus lived during the late Triassic period. The type...
Berlin–Ichthyosaur State Park may represent evidence of a gigantic cephalopod or Triassic kraken that killed the ichthyosaurs and intentionally arranged their bones...
East (leaf fragments) Androstrobus Triassic to Cretaceous, worldwide (leaf form genus) Antarcticycas Middle Triassic, Antarctica (known from the whole...
report of ostracods (Crustacea) associated with Bithynian (Anisian, Middle Triassic) Tubiphytes-microbial reef in the North Dobrogean Orogen (Romania)". Papers...
closer ancestors), were the only synapsids to survive beyond the Triassic. During the Triassic, the sauropsid archosaurs became some of the largest and most...
eruptions continued for roughly two million years and spanned the Permian–Triassic boundary, or P–T boundary, which occurred around 251.9 million years ago...
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