The Earth did quite alright before we came along, thank you very much. It developed in its own unique way, undertaking a four-and-a-half-billion-year journey all by itself. However, not too long ago, humans showed up and began making their mark. These human changes affected the Earth so much that geologists now want to declare a new geological epoch: the Anthropocene. Researchers have found unmistakable markers of this new chapter in Earth history in sediments around the world, for example in Crawford Lake in Canada. This has led them to the conclusion that it is time to declare the geological epoch of the Holocene officially over. For geobiologist and paleontologist Reinhold Leinfelder, these developments were reason enough to let time tell its own story; to let it be the star of its own “science graphic novel.”

Why Declare a New Geological Epoch?

In formalizing the Anthropocene as a new geological epoch, Leinfelder hopes to raise awareness for framing human experience within a more geological time frame as well in terms of the “Great Acceleration” in which we currently live. “You often hear phrases such as: ‘It’s not as bad as it seems; this kind of thing has happened before’ when people try to play down phenomena such as the global loss of coral reefs due to climate change. What these people fail to mention is that these ecosystems sometimes took five million years or so to recover – and in one case even 140 million years,” says Leinfelder, who is a member of the International Anthropocene Working Group (AWG) and professor emeritus of Freie Universität Berlin.

The working group advises the International Commission on Stratigraphy, or the “Parliament of Time,” as it is referred to in the graphic novel. The AWG was tasked with finding out whether it made sense to declare a new anthropological epoch, and, should all signs point to the Anthropocene being a verifiable geological epoch, how it could be defined.

The group has already published a great deal of research on the subject. “However, we also wanted to make sure that our results and the complexity of the topic were made available to the wider public in a more accessible format as well,” says Leinfelder. It is not the first time that Leinfelder has used graphic novels as a medium to present his research. “Slow media like these are puzzles consisting of pictures, stories, and informative texts. You have to give the reader space to work out information for themselves, as well as the freedom to skip sections or go back to something they have already read. It’s like a well-designed exhibition where visitors can still discover something new on their second or even third visit.”

It was with these criteria in mind that Leinfelder created the graphic novel Taming Time – A Golden Spike for the Anthropocene, together with Alexandra Hamann, responsible for the design and storyboard; illustrator Maki Shimizu; graphic designer Ines Gomes Ferreira; all in cooperation with members of the AWG.

The Laws of Time

At the beginning of the graphic novel, time is a mischievous, fluid being that winds its way through the history of the Earth. Initially depicted as black in color, time then takes on different hues in accordance with the global standards determined for different geological time periods. The roots of geology can be traced back to the sixteenth century, when Nicolaus Steno noted that in an undisturbed sequence of layers of sedimentary rock, each layer is younger than the one below it. Today, this is known as the law of superposition.

“In the eighteenth century, William Smith created the first geological maps and determined that different fossils were found in higher sediments than were found in deeper sediments,” explains Leinfelder. This is known as the law of faunal succession. These two principles – the law of superposition and the law of faunal succession – were key to relativizing time and dividing it into manageable chapters. However, it was only in the twentieth century that the absolute age of rocks could be determined using the radiometric dating method.

The graphic novel’s journey through time begins four billion years ago, in the Archean. This eon marks the beginning of life on our planet, when the unsung heroes of Earth’s history first came into being. The methane bacterium can be considered a true Earth system changer. These bacteria were key players in enabling the Earth to sustain life. “They make it clear that we are by no means the first beings to make our mark on the Earth,” says Leinfelder.

The detailed images of the graphic novel depict methane-producing bacteria consuming the hydrogen and carbon dioxide produced by the volcanoes that populated the surface of a very inhospitable Planet Earth. By producing methane as a byproduct, these bacteria created a greenhouse effect that ultimately built up an atmosphere around the planet.

These methane bacteria were followed by cyanobacteria, which developed photosynthesis and produced oxygen as well as iron bacteria that draw their energy from oxidizing iron and sulfur. “While this process did make use of the oxygen produced by the cyanobacteria, there was enough left over for life to continue to develop,” explains Leinfelder.

Keeping up with the Cnidarians

Now it was time for corals to enter the fray: sessile organisms that drew calcium from the oceans and secreted it in the form of organic limestone, which soon developed into large coral reefs. These would become underwater biodiversity hotspots. Meanwhile, flora began to take over on land, and the photosynthesis they carried out created more and more oxygen. Trees grew and died; the carbon they had captured during their lifetimes was then compressed into what is today coal. Microorganisms called plankton populated the waters. If they weren’t eaten by larger organisms, they later died and sank to the bottom of the sea, where they eventually became crude oil.

“My favorite hero in Earth history is grass,” says Leinfelder with a grin. “Finally, a plant that could be eaten but would grow back regardless!” Grasses enabled people to leave the forests and pursue sedentary lifestyles. The climate changed, rainforests declined, and grasslands took over. Humans were able to rely on a stable climate and could stay in the same place year-round. They cultivated grain from grass and were able to store it over the winter months, meaning that they were not restricted to living in tropical and subtropical regions and could support domesticated animals.

“Earthlings,” as the graphic novel calls us, are the most recent Earth system changers. However, our role is a much more ambivalent one: Unlike the other Earth system changers depicted in the graphic novel that changed the planet over a period of many millions of years, Earthlings have been around for a minute fraction of this time and have had just as great an impact. Within only a geological blink of an eye, we have added a “technosphere” to the Earth system. The natural biosphere, the part of the Earth inhabited by living organisms, is heavily outweighed by this technosphere, the totality of human-produced technological infrastructure. As geologists have now determined, the fossil legacy of humans includes glass, plastic, aluminum, and concrete.

A Golden Spike for the Anthropocene

Recently, the AWG suggested using the year 1950 to mark the beginning of the Anthropocene. This is because the plutonium isotopes from the hydrogen bomb tests that were being carried out during this time are key markers of human influence on the environment. In order to formalize the Anthropocene as a geological period in the Earth’s history, a geological reference site containing these markers must first be identified, described, and internationally agreed upon. The graphic novel depicts how researchers searched for the perfect site, narrowing down the selection from twelve candidates until they found a winner – Crawford Lake in Canada. Geologists hope that the lake can be used as a geological reference site (Global boundary Stratotype Section and Point, GSSP) that marks the beginning of the Anthropocene.

If the working group’s proposal is approved, this is the place where the golden spike – the traditional marker of a GSSP – will be placed. It is for this reason that the graphic novel’s subheading is “A Golden Spike for the Anthropocene.” How will the story continue for the biosphere, the technosphere, and the Earthlings? The epilogue jumps forward to the year 2100 and depicts three possible futures. But which path will we take? Only time will tell.

The Fun-damentals of Geology

The team behind the graphic novel have managed to create an entertaining resource that takes readers on a journey through the history of our planet. Taming Time is packed with humorous figures and explains scientific information in an easy to understand manner. It is an informative and entertaining read for researchers and geology or climate enthusiasts alike. It is currently available to download from Freie Universität’s Refubium server, with plans already in place to publish the graphic novel as a print version in multiple languages.

Students may recognize some parts of the graphic novel that deal with the Earth’s history, coral reefs, and the Anthropocene – topics that were frequently addressed by Leinfelder in his lectures. In this way, the graphic novel can be seen as a parting gift from Leinfelder, who has since retired from Freie Universität. The graphic novel is also a homage to Nobel prize winner Paul Crutzen (1933–2021), who coined the term “Anthropocene” at a conference in 2000 when he claimed: “We no longer live in the Holocene! We live in the Anthropocene!” and, in doing so, marked the beginning of a new chapter in Earth’s history.

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This article originally appeared in German in the Tagesspiegel newspaper supplement published by Freie Universität Berlin.