Humans have been altering nature for thousands of years – to shape a sustainable future, it’s important to understand that deep history

In July 2024, all eyes will turn to Paris for the Summer Olympic Games. Spectators from around the globe will converge on the City of Light to watch athletes compete and to soak in the culture, romance and history of one of the world’s most recognizable cities.

But an iconic Paris landmark, the Notre Dame cathedral, will still be under renovation^[1] after a devastating fire that ignited in the cathedral and burned for 12 hours^[2] on April 14, 2019. When the last embers were extinguished, most of Notre Dame’s wood and metal roof was destroyed, and its majestic spire had vanished, consumed by flames.

Notre Dame is nearly 1,000 years old and has been damaged and repaired many times. Its last major renovation was in the mid-1800s^[3]. The massive beams that framed the structure were fashioned from European oak trees harvested 300 to 400 years ago.

Today, these trees are common throughout north-central Europe, but few are tall enough to replace Notre Dame’s roof lattice and spire, thanks to centuries of deforestation. Planners had to search nationwide^[4] for enough suitably large oaks for the restoration.

As an archaeologist, I study long-term human interactions with nature^[5]. In my new book, “Understanding Imperiled Earth: How Archaeology and Human History Inform a Sustainable Future^[6],” I describe how addressing modern environmental crises requires an understanding of deep history – not just written human records, but also ancient connections between humans and the natural world.

Many people assume that the devastating impacts humans have wrought on our planet came about with the industrial era^[7], which began in the mid-1700s. But people have been transforming conditions on Earth for millennia. Looking backward can inform our journey forward.

From deforestation to reforestation

To see how this works, let’s consider the shortage of tall trees for Notre Dame from a wider perspective. Deforestation in Europe dates back at least 10,000 years to a time when early farmers swept across the continent, felling forests and creating agricultural and pastoral lands to form the landscapes of today^[8].

Based on archaeological evidence, pollen-based modeling^[9] and written records, scientists have determined that forest cover across northern, central and western Europe reached its highest density about 10,000 to 12,000 years ago, followed by a gradual decline over the intervening millennia. By AD 1700, people were farming on 250 million acres (100 million hectares) of agricultural fields, most of which had been created by clearing native European forests.

Millions of acres of timber became fuel for domestic hearths, and then for furnaces and boilers during the Industrial Revolution. This process was so transformative that renowned British geographer H. C. Darby, writing in 1954, called it “probably the most important single factor that has changed the European landscape^[10].”

Most of these forests were lost long before scientists could study them, but historical detective work can fill in the missing information. By identifying charred plant remains from ancient fire pits and analyzing pollen from lake and soil cores, archaeologists can map where ancient forests once flourished, determine which species were represented and reconstruct what forests looked like.

Today, European nations are working to restore forests across the continent^[11] in order to slow climate change and species loss. With historical information about past forests, modern scientists can make better choices about which tree species to plant, select the best locations and project how the trees may respond to future climate change.

Understanding what’s possible

In the past 50 years, the rate and scale of human impacts on Earth have intensified. In what scholars have dubbed “the Great Acceleration^[12],” human activities such as clearing forests, converting lands for farming and development, overharvesting wildlife and fisheries, and warming the atmosphere through widespread use of fossil fuels have altered conditions for life.

For people born during this era of dizzying change, it can be hard to picture life on Earth before humans remade it. Scientists have pointed out the danger of so-called “shifting baselines^[13]” – the widespread tendency to assume that the current depleted state of nature is how things have always been. Knowing how ecosystems used to look and function, and how human actions have changed them, makes the scale of conservation tasks more clear.

History offers insights into how the world once looked, long before globalization and industrial activities reshaped the planet. Discarded animal bones, charcoal fragments, broken stone tools and other flotsam and jetsam of the ancient past provide clues about the sizes and abundances of animal species, the location and composition of native forests and landscapes, and fluctuating atmospheric conditions. They also indicate how humans, plants and animals responded to these changes.

Informing a resilient future

The past can help modern societies confront today’s environmental challenges in innumerable ways. Understanding how takes careful historical detective work and scientific creativity. Here are a few examples:

• Tracing where Indigenous fisherfolk collected black abalone for over 10,000 years can guide restoration efforts for this endangered species^[14]. Numerous examples of effective Indigenous strategies are emerging from recent archaeological and anthropological research, showcasing innovative land management, sustainable agriculture and community resilience practices that have been honed over centuries^[15].

• Understanding the history of deforestation and land conversion patterns can help health experts anticipate future pandemics^[16]. Many infectious diseases move from wildlife to humans, and human activities such as deforestation and urbanization are increasingly bringing humans and wildlife into closer contact^[17]. This heightens the risk of zoonotic disease transmission.

• Museum collections can help scientists document and understand species declines^[18] and build effective strategies to fight the loss of global biodiversity. For example, museum collections of preserved amphibians have allowed scientists to track the spread of the deadly chytrid fungus, aiding in the development of targeted conservation strategies to protect vulnerable frog species.

References

1. ^{^} will still be under renovation (www.euronews.com)
2. ^{^} ignited in the cathedral and burned for 12 hours (www.bbc.com)
3. ^{^} in the mid-1800s (www.europeana.eu)
4. ^{^} search nationwide (www.smithsonianmag.com)
5. ^{^} long-term human interactions with nature (scholar.google.com)
6. ^{^} Understanding Imperiled Earth: How Archaeology and Human History Inform a Sustainable Future (www.smithsonianbooks.com)
7. ^{^} the industrial era (www.britannica.com)
8. ^{^} to form the landscapes of today (www.wiley.com)
9. ^{^} pollen-based modeling (doi.org)
10. ^{^} has changed the European landscape (press.uchicago.edu)
11. ^{^} restore forests across the continent (efi.int)
12. ^{^} the Great Acceleration (doi.org)
13. ^{^} shifting baselines (www.amazon.com)
14. ^{^} restoration efforts for this endangered species (doi.org)
15. ^{^} honed over centuries (theconversation.com)
16. ^{^} anticipate future pandemics (doi.org)
17. ^{^} into closer contact (theconversation.com)
18. ^{^} document and understand species declines (doi.org)
19. ^{^} Tim Evanson/Flickr (flic.kr)