Mammals will still recover from human destruction long after we leave

According to a new study released on Monday, humans have helped propel more than 300 species of mammals to extinction – equivalent to an incredible loss of 2.5 billion years of unique evolutionary history.

Researchers have estimated that it could go on for many millions of years before mammals develop enough new species to recover from the destruction caused by humans. The human species, however, will probably not survive to see the light of day.

"We are doing something that will last millions of years beyond us," said Matt Davis palaeontologist Aarhus University of Denmark, leading the new study, the devastating impact of being on biodiversity.

The new study, published in the Proceedings of the National Academy of Sciences, estimates that it could flow between 5 and 7 million years ago for mammalian diversity to return to its level. Before the arrival of the modern man – and this in the event that people would stop poaching, pollution and destruction of habitat over the next 50 years.

Like many scientists, Davis believes that the world is currently experiencing a sixth mass extinction, also known as Anthropocene extinction or caused by human activity. Davis told The Atlantic this week that "what we are experiencing now could have as big an impact as the asteroid" that killed most dinosaurs.

It's a "pretty scary" situation we've created, Davis said. "We are starting to shoot down the whole tree [of life], including the branch [humans] are sitting right now, "he told the Guardian.

For the study, Davis and his colleagues focused not only on the number of species that disappeared, but also on their evolutionary history (or the time that each species had spent evolving before disappearing).

As The Atlantic explained, this metric, called phylogenetic diversity, offers a useful perspective because some species are particularly unique and irreplaceable:

Pygmy sloth, for example, may be one of the most endangered mammal species, but it is also one of the youngest, having diverged from its closest relative 9,000 years ago. The aardvark, on the other hand, is the last survivor of a formerly very important group of mammals that separated from the others. million years ago. Losing pygmy laziness would be like tearing oneself away from a small branch of the mammalian family tree; losing the aardvark would be like sawing a whole branch.

The study revealed that since the advent of modern humanity until the sixteenth century, two billion years of the unique evolutionary history of mammals have been eliminated. Since then, humans have helped erase an additional 500 million years – and an additional 1.8 billion years could be lost over the next five decades if the high rate of mammalian extinctions persisted.

Davis said he hoped the new research would help guide conservation work, including helping to identify – and prioritize – endangered species with a long history of evolution. The study, for example, highlighted the black rhinoceros, the red panda and the indri, a large lemur endemic to Madagascar, as endangered animals with particularly long lineages. and unique.

"It's a lot easier to save biodiversity now than to change it later," Davis said in a press release.

However, in the end, one-time conservation efforts will not be enough to stem the tide of extinction and avoid "worst case scenarios," Davis said.

"In all honesty, the situation is likely to worsen," he told The Atlantic. "[We need] a massive and ambitious project on a global scale to which everyone will have to participate.

"It depends on the political will of politicians to make this happen," he added.