Remember Jurassic Park takes us back to the dinosaur age to you? Soaring, pterosaurs come from ferns .6500 million years ago, is said to be an asteroid impact led to this large lizard The extinction of the proliferation of two-legged animals, opened up a broad road,UGGs, the countdown to further the emergence of humans, but researchers are now challenging the authority of this! asteroid they believe may not be required for this major event responsible for the evolutionary history, So what strong reasons? This is what we need to care about it? may not.
when a scientific principle, even in grammar school has become a consensus, you know, it has long since gone beyond the scope of a theory established fact. extinction of the dinosaurs is one such example . mm in about 65 million years ago, as we already know, mm asteroid colliding with Earth, with the clouds blocking the sun so cool the planet live. In turn, this makes the extinction of the dinosaurs The emergence and proliferation of mammals has opened the way to provide the conditions. This mutation allows many species to extinction lightning speed, the fact is often understood as a single catastrophic event in 1978 near Chicxulub in Mexico found near the Yucatan Peninsula,UGG bailey button, a 112 miles long and nearly 65 billion years old crater ,cheap UGG boots, the more sure of this fact.
But now, a study published in the into question. the authors say, the impact of the planet and the extinction of the dinosaurs may not occur in the same period, about 300,000 years ago , but in separate incidents. This time is just geographically blink moment in time, but it is still a so-called instantaneous moment in ancient history, mm this time coordinate just right, could make a complete change in the extinction theory.
this controversial thesis by Gerta Keller of Princeton University and the University of Lausanne, Switzerland, together with Thierry Addate completed. researchers are well aware, as they challenge the theory of far-reaching is not easy. asteroids for the extinction of the dinosaurs show on earth 65 million years ago the same depth strata, all over the world there is a thin layer of iridium layer. Iridium is rare on Earth but common in asteroids elements; if the asteroid hit the ground, then as it should be should be able to find this material on a global scale the dust, they will affect the evaporation residue mixed in the rain will eventually fall to the ground again. The fossil record shows that in iridium layer below, extremely rich in species grow; in iridium layer above, 65% of species disappeared abruptly.
but Keller and Addate worry we have been misunderstood both the meaning of the geological and fossil record. They are many areas in Mexico, including a crater near the the area called El Penon was investigated. They iridium layer 30 feet higher than the depth of a sediment layer of particular interest. They calculated that sediment about 0.8 ~ 1.2 inch / 1000 the rate of subsidence, which It took all of 30 feet means that 300,000 years to put in place.
They analyzed the fossil beds of this small area, a total of iridium layer was calculated in the following 52 different species. Then they calculated the iridium layer species. The results showed that: the same above and below 52. until they are 30 feet above the ground in the sample, they find not the same species, that is, until 300,000 years later, they have found that the phenomenon of extinction of species.
and the sampling of species Addate's not decisive. many surveys since 1978 and the asteroid will be linked to species extinction. However, due to new mining and ground almost zero distance, so if any, should find the nearest point in time species loss more than the rest of the world. But the animals seem to have escaped unharmed. However, other paleontologists believe that El Penon and the impact region of similarity makes the results more credible. because the impact caused by the earthquake and Tsunami deposits may cause serious damage, making the discrete mix of rock and completely disrupt the rotation of geological time line. Keller does not agree, she noted that she and Addate sedimentary record of natural events such as sudden increase in physical and tsunami completely inconsistent.
Bi Xike Sulu Bo asteroid makes the extinction of dinosaurs,Bailey UGG boots, then what is causing the extinction of dinosaurs and disappearance? paleontologists in recent years has been committed to developing and promoting a variety of other theories, including the emergence of the continental shelf to allow different migration of species in different continents, resulting in the spread of disease makes the development of a local immunity has not yet infected species extinction. Keller and Addate still do not see any reason for making these theoretical explanations for the extinction of species so far deviate from the popular model. a atmospheric smoke obscured the sun may actually make the earth became cold and the dinosaurs could not adapt to mm but the smoke does not necessarily have to come from an asteroid. Instead, they say, the source of the smoke may be large volcanic eruptions, such as those in India's Deccan Plateau region south of volcanic eruptions, and their time in the history of the outbreak is also just right.
because dinosaurs 65 million years ago have become extinct, extinction is the extinction, the precise reasons for this are irrelevant. but in a large After the final disappearance of lizards , mammals feet was able to boom, this has a lasting charm.
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