A few years ago, during a visit to northern Italy, I had my first glimpse of the Permian-Triassic boundary: the rock record of the most severe mass extinction in Earth’s history, 250 million years ago. In contrast to the famous Cretaceous-ending meteorite impact that vanquished the dinosaurs, the Permian extinction played out over millennia, during a nightmarish period of biogeochemical mayhem triggered by rogue volcanoes and then amplified by a complex set of feedbacks in the ocean-atmosphere system. Seeing the raw chronicle of that event was more moving than I had anticipated.

The fossil-rich Permian rocks, bearing abundant mollusk and brachiopod shells and a profusion of tiny arthropods, convey the bustling activity of a healthy marine ecosystem11Enzo Farabegoli, M. Cristina Perri, and Renato Posenato, “Environmental and biotic changes across the Permian-Triassic boundary in western Tethys: the Bulla parastratotype, Italy,” Global and Planetary Change, vol. 55 (2007): pp. 109-135. .  But these forms are abruptly overlain by a dark, sulfurous layer that has the sinister character of a shroud. Those rocks are barren and mute, heart-rending testimony to a devastated world. The pathos of this stratigraphic contact—the contrasting worlds represented in just a few centimeters of rock—was almost unbearable. But then, I glanced north toward the sublime, fairy-tale beauty of the Dolomites, whose vertiginous cliffs represent middle-Triassic reefs that thrived in oceans that did eventually recover.22Baba Senowbari-Daryan, Rainer Zühlke, Thilo Bechstädt, and Erik Flügel, “Anisian (middle Triassic) buildups of the Northern Dolomites (Italy): The recovery of reef communities after the Permian/Triassic crisis,” Facies, vol. 28 (1993): pp. 181-256. I comforted myself by making that the happily-ever-after ending to the story of the Permian debacle, opting, for the moment, not to dwell on the fact that the world of those reefs was in turn destroyed in another mass extinction at the end of the Triassic.

As a geoscientist who is also a professor and writer, I think often about how to tell Earth’s story. Among the undergraduate classes I teach every year is “History of Earth and Life”—the entire 4.5-billion-year saga of the planet and the biosphere, condensed into a ten-week academic term.  This is an admittedly absurd undertaking—it’s clearly impossible to include all the details—so one must identify the most essential plot points in the narrative and tell a very condensed version of the story. But we spend a full week studying the end-Permian extinction, because it was such an inflection point for life on Earth; here in the Quaternary we still live in a global ecosystem shaped by the Permian cataclysm.

I struggle, though, to identify the genre of that event—and more broadly, how to characterize the entire arc of Earth’s biography. There are so many intersecting plotlines and characters. Is it a gothic horror story? A Shakespearian tragedy? A comedy of errors? A tale of grit and resilience?  The march of progress? Or just one damn thing after another? The sprawling annals of the geologic past are an amalgam of all of these: a young planet parts ways with its solar system siblings; it invents a biosphere that remakes the atmosphere; supercontinents form and break up as oceans close and open; ecosystems rise and fall as intervals of evolutionary innovation alternate with mass extinctions.

When we reach the Anthropocene, however, the nature of the narrative changes abruptly. In my reading of it, a new literary element becomes dominant: the unmistakable tone of irony.

Within the past decade or so, study of the Anthropocene has emerged as a new subdiscipline, with its own conferences, journals, and even post-graduate programs. In the geosciences, the focus has naturally been stratigraphic: how exactly do we define the moment in geologic time when we crossed the threshold and left the Holocene?

I admire the work of colleagues who have risen to this challenge and have proposed all manner of potential sedimentary markers, including radionuclides from nuclear testing; altered isotope values of carbon, nitrogen, and boron; spikes in metal and phosphorous concentrations; the appearance of microplastics and other novel materials; and various biostratigraphic signatures. The Anthropocene Working Group of the International Commission on Stratigraphy is also close to identifying a formal “golden spike” (Global Stratigraphic Section and Point, or GSSP) location as the type section for the new epoch. Candidates include Antarctic ice, speleothems in an Italian cave, peat from a bog in Poland, coral reefs from the Gulf of Mexico and the Coral Sea off the northeast coast of Australia, and muds from San Francisco Bay, the Baltic Sea, Japan’s Beppu estuary, a lake in eastern China and a reservoir in California. All of these proposals are meritorious, with careful rationales that meet the rigorous standards the ICS has required for all the other Golden Spike sites.

But as a geoscientist not directly involved in this process, I sense the impossibility of capturing the real meaning of the Anthropocene using the tools of the geosciences. This is the first of a nimbus of ironies that clouds my view of the Anthropocene. There will be no sharp stratigraphic markers of its cultural effects: the loss of hunting rituals and food traditions in arctic communities owing to vanishing ice; the rupture in collective memory for people evacuated from island nations in the face of sea level rise; the sorrow felt by those who live in landscapes irrevocably changed by drought and wildfire, industrial agriculture, and mountain top removal.  These intangible but very real signifiers of the Anthropocene will not be evident to a far future observer who may contemplate the thin layer marking its base, 250 million years from now—the same vantage point from which I pondered the Permian-Triassic boundary.

Such an observer would be able to discern the geochemical havoc that contributed to the end-Holocene mass extinction. However, without access to the extensive digital chronicles of late Holocene humans, this observer might not be able to understand that the ultimate culprit was not an errant meteorite or anomalous volcanic event, but instead a delusional belief system: a cult in which the free market was sacred, technology was the savior, and Nature was a mere commodity.  Nor would it be evident to a future stratigrapher that the most evangelical members of this cult came from the wealthiest fraction of the human population—and that they were not, in a particularly cruel irony, those who suffered most from the eventual consequences of its false doctrines.33A number of writers have taken issue with the term “Anthropocene” because it suggests that all of humanity is equally responsible for the environmental damage that defines it. Historian Jason Moore and others have suggested “Capitalocene” as an alternative. See, for example Jason W. Moore, “The Capitalocene, Part I: On the nature and origins of our ecological crisis,” Journal of Peasant Studies, vol. 44 (2017): pp. 594-630.

If such ironies will be invisible to future investigators, perhaps unearthing them now will help us in these early years of the Anthropocene.

There are multiple ironies concerning the role of geology in defining the Anthropocene. From its earliest days, geology has had to guard vigilantly against creationists and “young Earthers” prone to interpreting all rocks and landforms as records of the biblical Flood. Beginning in the 1830s with Charles Lyell, the high priest of uniformitarianism, generations of geologists have doggedly inculcated the public with the idea that geologic change is immeasurably slow and gradual. While some religious fundamentalists continue to resist this message, it actually has been absorbed by most citizens—and in fact appropriated by climate change deniers, who have used it to argue that nothing humans have done in our short existence could make any difference to a planet that is old, unresponsive, and slow-moving. When, in the 1980s, it became clear that some geologic changes can be rapid and catastrophic, and that humans could be pushing climate to a tipping point, geologists realized that two centuries of preaching about incremental change had been too effective. The economic and political sectors are now orthodox Lyellian gradualists while most geoscientists are neo-catastrophists.

Another, more obvious, irony is that geology, a field that came of age as it learned to locate the feedstocks for industrialization—coal, oil, natural gas, metal ores—is now the primary discipline sounding the alarm about the consequences of exploiting those commodities.

There are also unintentional ironies in the term Anthropocene itself. The new epoch we are naming for ourselves will be a time when Earth will become radically different from the planet that shaped us anthropoids into who we are. In this “human-dominated” time, we will in fact have less agency over our destiny than we enjoyed in the stable Holocene, when we had some grasp on weather prediction, some confidence in consistent water supplies, and some basis for believing the past would be a good guide for the future.

And there is the irony that to define the Anthropocene—an unnatural time division we created by assuming for decades that the natural world was dumb and inert—we are now designating dumb and inert objects to speak for us: ice, corals, stalactites, peat bogs, mud.

Although any observers from 250 million years in the future will find no remnants of these unfossilizable ironies, they will of course have one great stratigraphic advantage over those of us now struggling to define the dawn of the Anthropocene: the rock record of what happens next.

The evolutionary trends that will be the most obvious to future observers cannot be known to us: not just the fact of an extinction, but how ecosystems will have been altered by climate change and other powerful new selective pressures in a world with a different set of geochemical constraints. Already we have glimpses of how some lineages are being redirected. On the Turks and Caicos Islands in the Caribbean, a series of hurricanes has skewed the anole lizard population toward those with the strongest toepads for grasping trees in gale-force winds.44Colin M. Donihue, Alex M. Kowaleski, Jonathan B. Losos, et. al., “Hurricane effect on neotropical lizards span geographic and phylogenetic scales,” Proceedings of the National Academy of Sciences, vol. 117 (2020): pp. 10429-10434. We can anticipate that there will be equivalents to these “hurricane lizards” in other branches of the animal kingdom—species shaped more by catastrophe than by the everyday business of living. Perhaps in a few hundred million years, one of those lineages will give rise to an observer with an eye for stratigraphy.

Unlike the other geologic intervals whose beginnings—and endings—are well defined, we don’t know how the narrative of the Anthropocene will turn out. Perhaps the layer will simply be a notable anomaly—a useful tool for future global stratigraphic correlation, akin to the late Ordovician ash beds that record supervolcano eruptions in an Appalachian island arc.55Achim D. Herrmann, John T. Haynes, Richard M. Robinet, Jürgen Konzett, Norlene R. Emerson, “Insights into the tectonostratigraphic setting of the Southern Appalachians during the Blountian tectophase from an integrated geochemical analysis of magmatic phenocrysts in the Ordovician Deicke K-bentonite,” Lithos, vol. 398-399 (2021): p. 10631.  Or perhaps the base of the Anthropocene will mark a planetary inflection point like the Permian-Triassic boundary. We still have time to choose which story we wish to tell.

Not all ironies need be cruel or tragic. So let us decide to steer the plot toward a happy irony—and make the GSSP for the Anthropocene, the time named for human hubris, mark the start of a new epoch when humans finally learned to be ordinary Earthlings.

Marcia Bjornerud is Professor of Geosciences at Lawrence University in Wisconsin. Her research focuses on the physics of earthquakes and mountain building, and combines field-based studies of bedrock geology with quantitative models of rock mechanics.

Please cite as: Bjornerud, M (2022) Ironies of the Anthropocene. In: Rosol C and Rispoli G (eds) Anthropogenic Markers: Stratigraphy and Context, Anthropocene Curriculum. Berlin: Max Planck Institute for the History of Science. DOI: 10.58049/an7c-9w79