Extinct of dinosaurs has not led to the emergence of mammals today

How to trace the origin of all 4,500 fully and completely new Earth mammal species called ' tree of life ' shows that these mammal species have not grown much. form as a consequence of the extinction of dinosaurs. This is the content of a recent study published in Nature .

This study was conducted in the UK by researchers at Imperial College London and London Zoological Society (ZSL). It denies the theory that has long been acknowledged as a mass extinction event that caused the dinosaurs to become extinct 65 million years ago and this has led to the emergence of many mammals. that we see today.

This international team has been working for over a decade to synthesize tree charts of life from fossil samples and new molecular analysis methods. These fossils show that the ancestors (with genes) of the mammals we see today existed 85 million years ago and they survived the impact of a meteorite. into the earth . The collision is said to have made the dinosaurs extinct. However, during the white chalk (Cretaceous) period when the dinosaurs "wandered" on the earth, these species had very few numbers and these species did not evolve and develop extensively in the environment. ecology that dinosaurs dominate.

Picture 1 of Extinct of dinosaurs has not led to the emergence of mammals today

Tree chart of life
(Photo: Olaf RP Bininda-Emonds)

The tree of life charts indicates that after the mass extinction event, some mammal species have experienced a very rapid evolution and development period . However, most of these species have either been extinct completely, such as the Andrewsarchus (a very aggressive cow with a wolf-like appearance), or their diversity has been reduced like the group included. sloth and tatu.

These researchers believe that our ancestors and other mammal species living on the earth today began to disperse at a time when global temperatures began to rise after extinction. of dinosaurs 10 million years.

Professor Andy Purvis of the Department of Biology at Imperial College London explains: 'Our research shows that between 10 and 15 million first years after the extinction of dinosaurs, mammals nothing is remarkable today, but other mammal species are very developed. And it seems that the "warming up of the earth" later "activated" the diversity of today's species, not the dinosaur extinction.

This finding will rewrite our understanding of how we evolved on this planet and this study in general has given us a more concrete picture of how far we have been. ours in nature. '

Dr. Kate Jones of London's Zoology Society added: 'This study not only tells us that the extinction of dinosaurs did not create the evolution of mammals today, it also Give us more interesting information. It is important that scientists will use the results of this study to study and identify which animals will be endangered. The benefits for protecting animals globally are impossible to tell. '

The study was funded by the Royal Council of Natural Environment Research (NERC), the National Center (UK) for the analysis and synthesis of ecology (NCEAS), the Ministry of Education and Research German Federal Republic (BMBF), German Research Society, National Science Association (NSF), Columbia Research Institute of Earth and Columbia Center for Research and Development of Information Technology studying animal generation.

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