photo by Evan Spiler

Thanks to the growing human domination of natural systems on Earth, people say we are entering an Anthropocene Epoch, Grinspoon began, but what if the term “epoch” understates the consequence of what is going on? (The Holocene Epoch is only 11,700 years old.) Astrobiologists recently learned that planet formation is the norm in the universe, and now they’re trying to find out if life formation is also the norm. They won’t look for signs of mere geological epochs on other planets; they’re looking for eon-scale transitions like the three that Earth has gone through in its 4.8 billion years — all caused by life.

It has been 4 billion years since the Archean Eon began with the origin of simple life. Then 2.5 billions years ago the Proterozoic Eon unleashed “the Great Oxygenation Event” caused by cyanobacteria adopting solar energy (photosynthesis). “That’s when life took over the planet,” said Grinspoon. Everything accelerated further 542 million years ago with the Cambrian Explosion of complex life of plants and animals — the Phanerozoic Eon. Which we are still in. Or are we?

Alien astrobiologists could have noticed the Proterozoic Eon transition by detecting the dramatic destabilization of Earth’s atmosphere by the cyanobacteria. The Phanerozoic Eon transition would have been apparent from forest fires glowing on Earth’s night side, indicating combustible plant material. What would outside observers make of our current night side, blazing with dazzling cities? What would they conclude from bits of Earth firing off purposefully to orbit other planets and moons in the Solar System?

“Potentially,” Grinspoon suggested, “we’re at another eon boundary now, with an equally profound transition in the relationship between life and the planet, when cognitive processes become planetary processes. Is intelligence a planetary property, like life? Can it become a self-sustaining property, like life? Is civilization as adaptive as life is, or will it be a dead end?”

We can ask, what do humans have that similarly cataclysmic cyanobacteria did not have? We have awareness, intention, collaboration, and maybe a sense of responsibility. “The Anthropocene dilemma,” Grinspoon said, “is that we have global influence without global control. So far we’re acting like adolescent planet vandals.”

He concluded, “In order to choose a constructive role rather than a destructive role, we have to see ourselves in the very long time scale. If we can develop a mature, long-term, healthy relationship with world-changing technology, and if we proceed with a careful combination of restraint as well as innovation, our planet could become Terra Sapiens — Wise Earth.”

(Bonus point: When asked why people seem to be more worried about engineers hacking genetic code than hacking digital code, Grinspoon said, “Maybe it’s because the monsters we can imagine are scarier than the monsters we can’t imagine.” He added, “We tend to learn things through exploration, not through imagination.”)

The above is a summary of David Grinspoon’s Seminar “Earth in Human Hands”, presented as part of The Long Now Foundation’s Seminars About Long-term Thinking. Dr. David Grinspoon is an astrobiologist and Senior Scientist at the Planetary Science Institute. His research focuses on climate evolution on Earth-like planets, potential conditions for life elsewhere in the universe, and planetary-scale human influences on the Earth system. His books include Earth in Human Hands; Lonely Planets; and Venus Revealed.
To watch or listen to this Seminar, visit the David Grinspoon Seminar Page. To follow the series, you can become a Long Now Member, watch the videos, or subscribe to our podcast. Members help to support this series and can access tickets to the talks, our live stream, and HD video of our full catalogue of Seminars. Long Now started these monthly talks in 02003 to build a compelling body of ideas about long-term thinking.