The number of animals that surround us in just over a century, from 1900 to 2015, has halved. It happens everywhere on the Planet: south as north, east as west. Branches of giraffes, elephants, rhinos and oranges that gradually taper, sometimes even disappearing from some geographic areas. A depopulation of unimaginable proportions that has affected the entire ecosystem.
They are the first, theoretical, estimates of the “sixth global extinction”, as defined by three Stanford University biologists in a study just published in the Pnas scientific journal.
A phenomenon that goes beyond the individual specimens considered to have disappeared from the world, on average two every year. It is, for example, the case of Ciprinodonte Catarina (Megupsilon aporus), a species of freshwater fish, or the bats of Christmas Island, Australia. The latest news reveals that even the Emperor Penguin, in Antarctica, is not going very well. He will have to migrate to find other places to reproduce and hunt, otherwise he may not be over the end of the century.
The researchers analysed the geographical distribution of 27,600 species of vertebrates: birds, amphibians, mammals and reptiles. They have added detailed data from a sample of 177 well-trained mammalian specimens from 1900 to 2015.
In particular, the results show that more than 30% of vertebrates are declining both in terms of size and geographical distribution. Not only that, of the 177 mammals considered, everyone has lost at least 30% of their resident airliners. While over 40% have abandoned it more than 80%.
The most tangible are the tropical areas of the globe, where the wildlife left wide open spaces. With Africa becoming a leader, followed by Australia, Asia and Europe.
The consequences? “Destruction of the vital support system from which our civilization is totally dependent on food, many industrial products, and a liveable environment”.
However, there is a positive note, the scientist warns: “Since we are pulling this process into human activities, we can do a lot to minimize our impact and thus the proportions of the phenomenon.” Reducing pollution and exploiting resources, limiting trafficking in endangered species, helping poor populations to preserve biodiversity, are just some of the actions to be taken. “An international commitment is needed” – Ceballos points out – Also because “climate change is aggravating the situation”. And to act, “there remains a small window of time, which is closing fast.” The risk is to stay alone on Earth.