The Triassic (/ t r aɪ ˈ æ s. ɪ k / try-ASS-ik) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (), to the beginning of the Jurassic Period 201.36 Mya. 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.

The Late Devonian extinction consisted of several extinction events in the Late Devonian Epoch, which collectively represent one of five largest mass extinction events in the history of life on Earth. The term primarily refers to a major extinction, the Kellwasser event (also known as the Frasnian-Famennian extinction), which occurred around 372 million years ago, at the boundary …

Permian extinction, also called Permian-Triassic extinction or end-Permian extinction, a series of extinction pulses that contributed to the greatest mass extinction in Earth’s history. Many geologists and paleontologists contend that the Permian extinction occurred over the course of 15 million years during the latter part of the Permian Period (299 million to 252 million years …

Biological and Geologic Timeline of the Earth. The origin of the Earth and the Moon. ... Extinction Events There have been five major mass extinctions events: the terminal Ordovician (443 mya), Late Devonian (374 mya), terminal Permian called the "Great Dying" (251 mya), terminal Triassic (201), and terminal Cretaceous called the K/T event (65 ...

Biological evolution is the change in inherited traits over successive generations in populations of organisms. Adaptation is a key evolutionary process in which variation in the fitness of traits and species are adjusted by natural selection to become better suited for survival in specific ecological habitats. ... the Permian–Triassic, the ...

Jan 04, 2021 · Significant Permian events. During the Permian Period, Earth’s crustal plates formed a single, massive continent called Pangaea. In the correspondingly large ocean, Panthalassa, marine organisms such as brachiopods, gastropods, cephalopods (nautiloids and ammonoids), and crinoids were present. On land, reptiles replaced amphibians in abundance.

Mar 06, 2022 · This situation began to change in the late 1980s as scientists began to examine events such as the climate transition that occurred at the end of the Younger Dryas about 12,000 years ago (e.g., Dansgaard et al., 1989) and the large swings in climate during the glacial period that have come to be termed “Dansgaard-Oescher events” (“D-O ...

Standard 8-2.4: Recognize the relationship among the units—era, epoch, and period—into which the geologic time scale is divided. Eons: Longest subdivision; based on the abundance of certain fossils Eras: Next to longest subdivision; marked by major changes in the fossil record Periods: Based on types of life existing at the time