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Scientists warn that Earth’s sixth mass extinction has already started

Scientists warn that we are experiencing the beginning of the sixth mass extinction… and guess what? We are the cause of it! Because of the human behavior in the last centuries, 320 species of animals have disappeared, a phenomenon that threatens the planet’s biodiversity and even the human species. In a new scientific article published on sciencemag.org, an international team of researchers came to this dreadful conclusion: while the previous extinctions were caused by natural planetary transformation or catastrophic asteroid collisions, the phenomenon we are experiencing today is influenced by the human activity.

The study coordinator, Rodolfo Dirzo, professor of biology at Stanford, made a reference to the “Defaunation in the Anthropocene”. Since 1500, we lost over 320 terrestrial vertebrates, and the remaining population is declining by 25%. The situation is similar for the invertebrates, since it is estimated that between 16% and 33% of the species are threatened or endangered around the globe. Large animals (with a lower growth rate and fewer offsprings) including elephants, rhinos, polar bears and many other species, are facing the highest rate of decline, a trend that has accompanied the previous five extinctions.

Although these large species represent a relatively low proportion of animals, their extinction will trigger effects that might adversely affect the stability of other species and, in some cases, even humans.



Just like the case of large animals, extinction is determined primarily by habitat loss through the accelerated process of urbanization. The last mass extinction occurred during the Cretaceous 144-65 million years ago, when Earth’s collision with an asteroid led to the extinction of the dinosaurs.

article source: news.com.au