03.04.11. American scientists claim that humanity is approaching a massive extinction of all life, as tens of millions of years ago, when the Earth with dinosaurs disappeared.
According to the authors, the results of which were published in the journal Nature, if we do not take action, the deleterious effects of human activities on ecosystems will have for several centuries to a full 75% of the extinction of all life on our planet. Restoration of life after such an event of apocalyptic scale delayed for millions of years.
To such a disappointing conclusion the American scientists led by Professor Anthony Barnoski biology at University of California at Berkeley after the study, the purpose of which was to determine the rate at which mammals are disappearing. It turned out that in the last 500 years of the 5570 species of mammals became extinct at least 80. The usual rate of extinction of mammals — approximately two species per million years, ie much less than now.
"If the animals that are now threatened with extinction — says Professor Barnoski = really disappear and fauna will continue to die at the same rate, the sixth mass extinction of life can begin within 3 — 22 century."
According to scientists, it will be the main culprits of people exterminating animals, introducing a system of alien species, spectacular fauna habitat, spreading disease, and finally changing climate.
Total mass extinctions of life in the history of the Earth over the past half-billion years, there are five.
The earliest disappearance of life occurred in the late Ordovician period (440 million years ago), then disappeared almost all the corals with fish and 25% of all families. Mass death of living creatures most likely caused the formation and further melting of glaciers, causing the water level in the oceans, seas, first down, then got up.
At the end of the Devonian period (370 million years ago) too for some strange reason, many species have become extinct, and 70% of marine invertebrates. At the end of the Permian period (250 million years ago), the planet has lost 80% — 96% of all marine life and 70% of the land. Two recent mass extinction occurred in the Triassic period — 200 million years ago in the Cretaceous 65 million years ago. The reason for the disappearance of the latter was a collision of Earth with a large asteroid in Mexico, which killed 76% of all animals, including the dinosaurs.