At the end of the Triassic about 201 million years ago, the Earth experienced a major biological extinction event, commonly known as the Triassic-Jurassic extinction (Tr-J Mass Extinction).The incident has had a profound impact on both oceans and land, especially in the oceans, where about 23% to 34% of marine species disappear in this extinction, which has led the scientific community to conduct in-depth research on its causes, impacts and future implications.
The cause of this event may be related to the widespread volcanic activity in the Central Atlantic Volcanic Province (CAMP), which releases a large amount of carbon dioxide, causing global warming and ocean acidification.
Early research on end-Triassic extinction can be traced back to the mid-20th century, when scientists generally believed that natural history events occurred step by step, so gradual environmental changes were considered the main cause of extinction.However, as Jack Sepkoski discovered a sharp decline in biodiversity on the Triassic-Jurassic border in the 1980s, the event was redefined as one of the "Five" extinction events.Some studies have even suggested that this event may be related to asteroid impacts, but over time, there has been a scientific consensus on the extinction theory triggered by volcanic activities of CAMP.
The Triassic-Jurassic extinction event completed the transition from Paleozoic evolutionary fauna to modern evolutionary fauna.According to the study, about 23% to 34.1% of invertebrate species in the ocean suffer extinction.In this incident, some groups such as amber shellfish and seaflies were almost completely eliminated, while other species such as coarse-leaved shellfish, although severely damaged, escaped most of the losses in diversity.
The diversity of corals has been severely damaged, with about 96% of coral groups almost disappearing after extinction, creating a "coral gap" for Hetanzian.
Unlike invertebrates, fish did not face mass extinction at the end of the Triassic.Nevertheless, marine reptiles experienced a significant decline in diversity during the Mesotriassic and Jurassic periods, but were not high in extinction rates, and most famous marine reptiles did not face the crisis of extinction during this period.
The Triassic-Jurassic extinction event has a more serious impact on terrestrial animals than marine animals. Studies have shown that 42% of terrestrial tetrapods became extinct at the end of the Triassic, especially ancient reptiles, and new groups such as dinosaurs and pterosaurs have begun to replace them.
At the end of the Triassic period, the ecological niches of many terrestrial reptiles were occupied by emerging groups such as dinosaurs, thus forming a monopoly situation for dinosaurs, which lasted for 135 million years.
The impact of this extinction event is not limited to animals, but the plant world has also undergone significant changes.According to estimates, the extinction rate of plants was as high as 73% in some areas at the end of the Triassic period.Although the loss of plant diversity worldwide is not severe, plants in some regions do face significant extinctions, especially in the Newark Supergroup formation in eastern North America.
Part of the reason for plant extinction can be attributed to a significant increase in carbon dioxide concentrations, which in turn is directly related to volcanic activity.
For the causes of the Triassic-Jurassic extinction event, a theory is widely accepted that widespread volcanic activity from the Central Atlantic Volcanic Province releases a large amount of carbon dioxide, leading to global warming and other environmental changes.These volcanic activities are accompanied by major carbon isotope events that correspond precisely to the time of extinction.
The extinction event at the end of the Triassic not only changed the composition of the Earth's ecosystem, but also shaped the subsequent era dominated by dinosaurs.Different biological groups and environmental changes are intertwined, demonstrating how biodiversity changes rapidly and drastically in the history of the earth.The revelation this incident brings to modern scientists is whether life can adapt and prosper again when a drastic event occurs?