Chattanooga Times Free Press

Scientists vote down starting new epoch in Earth’s history

- BY RAYMOND ZHONG

The Triassic was the dawn of the dinosaurs. The Paleogene saw the rise of mammals. The Pleistocen­e included the last ice ages.

Is it time to mark humankind’s transforma­tion of the planet with its own chapter in Earth history, the “Anthropoce­ne,” or the human age?

Not yet, scientists have decided, after a debate that has spanned nearly 15 years. Or the blink of an eye, depending on how you look at it.

A committee of roughly two dozen scholars has, by a large majority, voted down a proposal to declare the start of the Anthropoce­ne, a newly created epoch of geologic time, according to an internal announceme­nt of the voting results seen by The New York Times.

By geologists’ current timeline of Earth’s 4.6-billion-year history, our world right now is in the Holocene, which began 11,700 years ago with the most recent retreat of the great glaciers. Amending the chronology to say we had moved on to the Anthropoce­ne would represent an acknowledg­ment that recent, humaninduc­ed changes to geological conditions had been profound enough to bring the Holocene to a close.

The declaratio­n would shape terminolog­y in textbooks, research articles and museums worldwide. It would guide scientists in their understand­ing of our still-unfolding present for generation­s, perhaps even millennium­s, to come.

In the end, though, the members of the committee that voted on the Anthropoce­ne over the past month were not only weighing how consequent­ial this period had been for the planet. They also had to consider when, precisely, it began.

By the definition that an earlier panel of experts spent nearly a decade and a half debating and crafting, the Anthropoce­ne started in the mid-20th century, when nuclear bomb tests scattered radioactiv­e fallout across our world. To several members of the scientific committee that considered the panel’s proposal in recent weeks, this definition was too limited, too awkwardly recent, to be a fitting signpost of Homo sapiens’ reshaping of planet Earth.

“It constrains, it confines, it narrows down the whole importance of the Anthropoce­ne,” said Jan A. Piotrowski, a committee member and geologist at Aarhus University in Denmark. “What was going on during the onset of agricultur­e? How about the Industrial Revolution? How about the colonizing of the Americas, of Australia?”

“Human impact goes much deeper into geological time,” said another committee member, Mike Walker, an earth scientist and professor emeritus at the University of Wales Trinity Saint David. “If we ignore that, we are ignoring the true impact, the real impact, that humans have on our planet.”

Hours after the voting results were circulated within the committee early Tuesday, some members said they were surprised at the margin of votes against the Anthropoce­ne proposal compared with those in favor: 12-4, with two abstention­s. (Another three committee members neither voted nor formally abstained.)

 ?? GORDON WELTERS/THE NEW YORK TIMES ?? Draglines operate in 2015 at the Welzow-Süd coal mine near Welzow, Germany.
GORDON WELTERS/THE NEW YORK TIMES Draglines operate in 2015 at the Welzow-Süd coal mine near Welzow, Germany.

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