Dinosaurs are close relatives of reptiles. They dominated in the kingdom of animals for millions of years. Their fossilized remains meet on all planet. Paleontologists still did not come to a uniform solution of mysterious disappearance of dinosaurs.
Time of dinosaurs
Before to domination of dinosaurs the end came, these animals prospered on Earth. The planet was inhabited by hundreds of different types of lizards, predatory and herbivorous, four-footed and biped.
Sudden death
Fossilized remains of dinosaurs cease to meet in deposits by age less than 65 million years. It proves that the last representatives died out after this period.
The set of hypotheses of their disappearance was made. Some researchers saw the reason in competitors of dinosaurs – the mammals eating eggs of lizards. Others made a hypothesis of mass epidemic (bacterium or a virus) which struck dinosaurs.
However they were not the only animals who disappeared 65 million years ago. At the same time from a face of Earth the set of reptiles, Amphibia, mammals and fishes was gone. This extinction in the kingdom of animals led to the global crisis which struck not only dinosaurs. It is also known that it occurred sharply.
Having studied deposits, paleontologists established that remains of dinosaurs ceased to meet suddenly, in borders of one thin layer of clay. It also allowed to date accident time precisely.
Space version
In 1980 the geologist from the University of California Luís Walter Alvares found in clay deposits metal, rare for our planet, – iridium. To Earth it gets thanks to the meteorites arriving from space. Then Alvares assumed that the huge celestial body faced our planet 65 million years ago. It could lift a huge cloud of dust and ship all Earth in darkness. The theory was confirmed when fragments of minerals were found in clay. Also the crystals rich with nickel were found. They are scattered by a meteorite, passing through the terrestrial atmosphere.
Volcanic version
Long time group of researchers considered that in disappearance of dinosaurs a role was played by volcanoes. Large eruptions of volcanoes began in India 65 million years ago. Perhaps, they led to a cold snap. For confirmation of the theory the geologists wrote off the iridium and fragments of minerals found in clay for result of eruptions of volcanoes. On the other hand, eggs of dinosaurs on the place of eruption are found In India. It proves that they did not die out after that.
Whether the danger threatens us
Whether space disaster which happened at the time of dinosaurs can repeat on Earth? Dangerous asteroids and comets orbit our planet constantly. And there is a lot of them, but they are rather small. Scientists counted that the body of so huge sizes can fall to the Ground approximately time in 100 million years.