Humankind’s footprint on planet Earth is now so deep that scientists argue we need to have our own epoch named after us: the Anthropocene.

Epochs are traditionally measured in terms of millions of years — longer than an age, but shorter than a period. Since humankind has been living on the planet for little more than a blink-of-an-eye in geologic time, that’s saying a lot. According to the Cosmic Calendar, an eye-opening chart that distills the 13.8 billion year history of the universe down to a single year, humankind’s early ancestors first walked upright at 10:30pm on the final day of December. Modern humans evolved at 11:52pm; the early human migrations out of Africa happened some time between 11:56pm and 11:59pm.

Everything we know and have achieved — from the early cave paintings to the beginnings of agriculture, permanent settlements and so on, to reading, writing, art, music, the Industrial Revolution and the age of the Internet, has happened in the final minute of the last day of the 12th month of the Cosmic Calendar year.

That’s a pretty sobering thought when you consider that roughly 1.2 seconds ago in geologic time, Columbus arrived in America; everything from overpopulation and human-influenced climate change to the despoiling of the rain forest, fouling of the oceans and mass extinctions has unfolded since then.

Geologists don’t just identify epochs out of thin air. An epoch has to leave a geological imprint in solid rock — in sediments buried below the ground, in ice glaciers (now melting) or on canyon walls, if you like. The Anthropocene epoch, many of these geologists now argue, is an actual thing because evidence of human activity is now being imprinted in geological formations. “We are mining the planet’s surface, acidifying our oceans, creating new rock layers laced with plastic, and exterminating many species,” science editor Robin McKie wrote this past weekend in London’s Sunday Observer. “The consequences of these actions will be detectable in rocks for millions of years.”

A new study by University College of London researchers Simon Lewis and Mark Maslin identifies colonialism — the way guns, germs and steel shaped the New World — as the prime mover behind the tectonic shift on the geologic timescale; other scientists cite the detonation of the first atomic bomb as the moment when the Anthropocene epoch dawned (their argument being that the earliest atomic bombs left a radioactive record in Earth’s rocks), while still others point to the proliferation of plastics, which are forming their own geological layers by becoming embedded in rocks.

The real question, of course — and the great unanswerable — is how the Anthropocene epoch will shape and change planet Earth, and whether our home world can survive it, or whether, as geological time has shown over the ages, epochs and periods, nothing is forever and all life changes eventually, even life itself.

“We have become a new force of nature, dictating what lives and what goes extinct,” Maslin told the Sunday Observer. “Although, in one crucial respect, we are unlike any other force of nature: Our power, unlike plate tectonics or volcanic eruptions, is reflexive. It can be used, modified or even withdrawn.”

“It would be wise,” Maslin and Lewis wrote later on the BBC’s website, “to use this immense power to give the best chance for people, and the rest of life, all to flourish.”

https://www.bbc.com/news/science-environment-44389413

https://www.theguardian.com/science/2018/jun/10/colonialism-changed-earth-geology-claim-scientists

Scientists could have been forgiven for thinking when, six years ago, paleontologists examining rocks in Greenland found what they believed to be the oldest fossils on Earth. The remnants of life dated back to a time when scientists believe Earth’s skies were orange and the seas green, when massive tectonic plates splt apart in giant seas of molten lava.

©Laure Gauthiez/Australian National University via AP

That changed earlier this week with University College London’s revelation that an international team of researchers in Quebec unearthed the fossilized remains of a creature that lived some 3,7 million years ago. The remains could even be as old as 4.3 million years, researchers say.

One link between the two finds is climate change. The 2012 fossils were found in a newly melted part of Greenland, where a team of researchers examined terrain that had been unexposed to open air for tens of thousands of years.

The new findings were made in a northern clime as well: the Nuvvuagittuq Supracrustal Belt in Quebec, on the eastern shores of Hudson Bay. There may well be more, similar finds as the polar ice caps melt and recede.

The newly discovered fossils aren’t easy to spot. These aren’t woolly mammoth tusks or the skeletal remains of one of humankind’s early ancestors, but rather microbes, microrganisms individually too small to be seen with the unaided eye. The Nuvvuagittuq fossils are tiny fialments and tubes formed by bacteria that live on iron. The researchers would have had to know what they were looking for, and some idea where to find them.

The fossils may be small, but they’re meaningful — especially in a time when global news events are most depressing than enlightening.

UCL PhD student Matthew Dodd, author of the study published in the journal Nature, said the fossils support the idea that life emerged from hot, sea-floor vents shortly after the Earth formed. The evidence fits with other evidence — the Greenland findings, for one — of microorganisms believed to have formed the foundation for early life forms.

©Matthew Dodd, University College London

The Nuvvuagittuq Belt, much like Africa’s Great Rift Valley, has proved a boon for paleontologists studying the originis of life. This part of Quebec is home to some of Earth’s oldest rock formations, dating back some 4.28 billion years. Earth is believed to have formed some 4.6 billion years ago. What are towering rock formations today once lay on the sea floor, when Earth and Mars would both have been covered by water.

Dodd said the find suggests there may have been life on Mars as well, some 4,000 million years ago.

If not, he wrote in Nature, it would suggest Earth was unique — an exception amond exceptions.

Dodd’s research for University College London was supported by NASA, Carnegie Canada and the UK Engineering and Physical Sciences Research Council. The findings have since been reported by BBC and in the Washington Post, Wired and Chicago Tribune, among others.

Why does it matter? For one, the discovery shows life may have formed more quickly than once thought. Scientists originally believed it would take life nearly a billion years to gain a toehold once the molten Earth cooled enough to sustain life.

Now it appears life may have formed virtually overnight, in geological terms.

The study is likely to be contentious. Claims about early life often are. Either way, though, it’s one more potential piece in the puzzle of life on Earth.

“This discovery answers the biggest questions mankind has asked itself,” Dodd told the BBC. “It’s very humbling to have the oldest known lifefroms and your hands and be able to look at them and analyze them.”

Journal

“Man is modifying the world so fast and so drastically that most animals cannot adapt to the new conditions. In the Himalaya as elsewhere there is a great dying, one infinitely sadder than the Pleistocene extinctions, for man now has the knowledge and the need to save the remnants of his past.”

— Peter Matthiessen

Of angels and demons: How humankind changed the planet and created the Anthropocene epoch.

Earliest yet signs of life-on-Earth found in Canada.

Journal

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