The Cretaceous Extinction Event

The cause of the Cretaceous extinction, the evidence and the impact on biodiversity occurred in the most important events of Cretaceous. About 65 million years ago, the second most serious mass extinction occurred in the history of the earth. This led to a reduction of about 80% of the living species at the time. Although not as serious as the ultimate mass extinction of the Permanent, the Cretaceous extinction was the most famous mass extinction. This is caused by dinosaurs, the chapter of the earth history that it closed and the violent incident that made it extinct.

Cretaceous - Paleogene extinction event (end of Cretaceous, K-Pg annihilation, or previous K-T annihilation): 66 Ma - transition zone of the Cretaceous Dania era (Maastricht). The event formerly known as Cretaceous - Tertiary or K - T extinction or K - T boundary is now called Cretaceous - Current (or K - Pg) extinction event. About 17% of families, 50% of all genera and 75% of species are extinct. In the sea, ammonite, Presiosaurus, moss all disappeared and the proportion of adherent animals (immovable animals) decreased to about 33%. In the meantime, all the dinosaurs except birds have become extinct. Boundary events are serious, there is a big difference in annihilation rate between different clades. Mammals and birds, the latter from the animal dinosaur dinosaurs, became the predominant large terrestrial animal

Cretaceous - Quaternary extinction does not mean that all dinosaurs are extinct. Birds evolved from Jurassic small feather beasts, and most dinosaur strains were cut off at the end of the Cretaceous, but some birds survived. Therefore, dinosaurs are part of modern fauna. Mammals did not evolve from modern reptile populations, but instead mammals and reptiles evolved from a common ancestor. Immediately after the first reptile - like animals appeared, they were divided into two branches, a lizard and a synapse. The line leading to mammals (synapse) is separated from the line leading to the modern reptile line (lizard) in the middle of the coal era about 320 million years ago. For the first time in the late Carboniferous or early Permian, contemporary reptiles (Lepidoptera, Tortoise and Crocodile) opposed. Mammals themselves are the only survivors of the synaptic system.