Dinosaurs
The Permian-Triassic (P-Tr) Extinction Event is widely recognised as the greatest extinction event on Earth. It is also known as the "Great Dieing".It occurred 251 million years ago marking the end of the Permian Period and the start of the Triassic Period.It also marks the end of the Paleozoic Era and the start of the Mesozoic Era. Estimates have suggested that 96% of marine species and 70% percent of land vertebrate species became extinct. It is also the only known mass extinction of insect with 56% of insect families and 83% of insect genera becoming extinct.Little is known of the cause of the mass extinction but theories range from meteorite impacts, to volcanism, to sea level fluctuations.
The event that marks the division of the Paleozoic and Mesozoic era is the breaking up of the Pangaea
The Cretaceous Period was the 3rd geological period in the Mesozoic Era. The end of the period would see the extinction of all non-avian dinosaurs as well as all the large marine reptiles, pterosaurs as well many other species of animals and plants. It lasted from 145.5 to 65.5 million years ago. It was the time between 2 extinction events, the smaller End Triassic Extinction event and the larger K-T Exinction event.
The Mesozoic period began about 250 million years ago when the Permian-Triassic extinction occurred, probably by a combination of gradual atmosphere change and some external event like an Earth impact. The period ended about 66 million years ago with another great extinction, this one probably a combination of an impact and volcanic activity.
Mass extinction. A mass extinction typically occurs after a catastrophic global event. This event could be a bolide impact (such as the impact 65 million years ago that killed the dinosaurs, the most famous example of a mass extinction), increased volcanism, climate change, or something similar.
An asteroid impact
A mass extinction
There were major asteroid impacts. #fuckschool #imheretohelp
The Cretaceous- Tertiary Extinction
The Permian-Triassic extinction event. Also known as the P-Tr extinction or the Great Dying, where 96% of all life died out.
Scientists believe the Cretaceous-Paleogene extinction event, or the plants dying at the end of the Mesozoic Era, was caused by a massive asteroid/comet impact. The theory suggests that the impact had catastrophic effects on the environment, including an impact winter, which prevented the plants from carrying out photosynthesis.
That would be 251 million years ago. The end of the Paleozoic era marks the beginning of the Mesozoic. The last period of the Paleozoic era was the Permian, and the first period of the Mesozoic era was the Triassic; hence the extinction event (the biggest extinction event in the earth's history), the Permian-Triassic extinction, which defines the border between the eras.
The event that marks the division of the Paleozoic and Mesozoic era is the breaking up of the Pangaea
The Permian-Triassic (P-Tr) Extinction Event is widely recognised as the greatest extinction event on Earth. It is also known as the "Great Dieing".It occurred 251 million years ago marking the end of the Permian Period and the start of the Triassic Period.It also marks the end of the Paleozoic Era and the start of the Mesozoic Era. Estimates have suggested that 96% of marine species and 70% percent of land vertebrate species became extinct. It is also the only known mass extinction of insect with 56% of insect families and 83% of insect genera becoming extinct.Little is known of the cause of the mass extinction but theories range from meteorite impacts, to volcanism, to sea level fluctuations.
The Cretaceous Period was the 3rd geological period in the Mesozoic Era. The end of the period would see the extinction of all non-avian dinosaurs as well as all the large marine reptiles, pterosaurs as well many other species of animals and plants. It lasted from 145.5 to 65.5 million years ago. It was the time between 2 extinction events, the smaller End Triassic Extinction event and the larger K-T Exinction event.
Ammonites were an abundant group of mollusks during the Mesozoic. However, the K-T extinction event, which wiped out the dinosaurs, was too much for them. They became extinct 65.5 million years ago.
Avian dinosaurs survived the extinction event of the dinosaurs.