There's no getting back to nature: humanity has been changing Earth's landscape for millennia

Neanderthal man thinks about what he's done. (Okay, he was probably extinct already.) Image: AFP/Getty.

What is natural? It is often assumed that natural is better than artificial. Getting back to nature is something we should aspire to, with kids in particular not spending enough time in nature.

But if you want to escape civilisation and head into the unaltered wilderness you may be in for a shock: it doesn’t exist.

New research now suggests that there are practically no areas that have escaped human impacts. But not only that, such impacts happened many thousands of years earlier than is usually appreciated. In fact, you’d have to travel back more than 10,000 years to find the last point when most of the Earth’s landscapes were unaffected by humans.


The study, published in the Proceedings of the National Academies of Sciences and led by Nicole Boivin of the University of Oxford, catalogued changes in the abundance and diversity of plants and animals at the same time as human societies and technologies spread across the globe.

There is good fossil evidence for modern humans – Homo sapiens – being present in East Africa as far back as 195,000 years ago. Some 180,000 years later, humans were found on every continent except Antarctica. Over this period there were a series of collapses in biodiversity, with particular instances of extinctions of megafauna, non-domesticated land animals weighing more than 44kg.

Between 50,000 to 10,000 years ago, at least 101 of the 150 groups of megafauna species became extinct. There is much debate as to whether the disappearance of megafauna such as mammoths or mastodons was a direct result of human hunting, or a response to other factors. Correlation does not necessarily lead to causation: so evidence that large number of species disappeared from some regions around the same time as humans appearing could be due to a common factor such as changes in climate as the glaciers of the last ice age retreated.

Boivin’s study doesn’t produce a smoking gun that proves humans were responsible for such extinctions. Rather it uses traditional and new archaeological techniques to produce flint axes, plant pollen and burnt forest remains as evidence of the impacts humans had.

Extinction grabs our attention, but the data the international team has assembled tells a story of rapid change in not just the total number of species around the time that humans appear, but also the numbers of individual plants and animals in these ecosystems. Hunting and land clearing are the two main culprits in the oldest period they study – the Late Paleolithic (ending 10,000 years ago).

The study maps the spread of crops like wheat (A, in red) and livestock (Cattle, in blue) against the spread of human civilisation. ImagE: Boivin et al/PNAS.

After that, impacts shift up a gear with the development and rapid spread of agriculture. By this time roving bands of hunter gatherers begin to settle and plant crops and herd cattle. Today, we are used to looking out of an aircraft window to see broad expanses of intensively farmed monoculture crops. This trend began with the very first farmers who replaced diverse habitats with a small number of cultivated plants that in time would spread across the Earth, replacing whatever ecosystems they encountered.

The development of agriculture also included the domestication of animals, a few of which have expanded their ranges along with humans. Domestication of chickens happened some 10,000 years ago in East Asia. Earth is now home to over 20bn chickens, making it the most abundant bird species by some margin. The vast majority of the mass of land animals is now made up of humans and their domesticated species of cattle, pigs, sheep, goats and chickens.

When you include the accidental introduction of animals such as rats and invasive plant species, human agriculture meant profound alteration or sometimes complete replacement of indigenous ecosystems. The starkest examples of such changes are to be found on islands which often have high numbers of species that are not found anywhere else. Some examples are documented in more recent human history – the 17th-century extinction of the flightless dodo from the island of Mauritius being the most famous.


As well as detailing some of the havoc that humans have wrought on the biosphere, the researchers also highlight some positive interactions humans had. For example, the long presence of prehistoric societies that flourished within the Amazon basin show that careful stewardship of ecological resources – in that instance the cultivation of rich productive soils – can enhance ecosystems and provide sustainable livelihoods.

This is perhaps the most important lesson gained from the study. If we are to feed and care for the 9bn people that will be living on Earth by the middle of this century, then we need a more subtle and complex understanding of nature and sustainability.

The industrial age we now live in has taken human impacts to a planetary scale. We are changing the global climate and some argue that we have become a geological force. We can neither get back to nature nor continue as we are.

The state of nature – the situation of humans before the formation of societies – is a well used thought experiment in philosophy. It asks us to consider how societies and governments arise. What makes a good society? What is the moral basis of taxation?

An ecological state of nature – the biosphere as it was before human interference – is sometimes used in a very limited way when managing contemporary ecosystems. The assumption can be that we should simply strive to revert them back to their natural state. But can we say what that state is?

Alternatively, it could be used to pose both philosophical and practical questions. What sort of Earth system do humans want to live on? What is the role of other species in human well-being? What is the moral status of non-human animals?

Research that probes our ancient interactions with the rest of life on Earth can help us address such questions and so understand our current predicament. It remains to be seen whether Homo sapiens – which let’s remember is Latin for wise person – have the intelligence to learn from past mistakes and forge a sustainable future on Earth.The Conversation

James Dyke is lecturer in sustainability science at the University of Southampton.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Urgently needed: Timely, more detailed standardized data on US evictions

Graffiti asking for rent forgiveness is seen on a wall on La Brea Ave amid the Covid-19 pandemic in Los Angeles, California. (Valerie Macon/AFP via Getty Images)

Last week the Eviction Lab, a team of eviction and housing policy researchers at Princeton University, released a new dashboard that provides timely, city-level US eviction data for use in monitoring eviction spikes and other trends as Covid restrictions ease. 

In 2018, Eviction Lab released the first national database of evictions in the US. The nationwide data are granular, going down to the level of a few city blocks in some places, but lagged by several years, so their use is more geared toward understanding the scope of the problem across the US, rather than making timely decisions to help city residents now. 

Eviction Lab’s new Eviction Tracking System, however, provides weekly updates on evictions by city and compares them to baseline data from past years. The researchers hope that the timeliness of this new data will allow for quicker action in the event that the US begins to see a wave of evictions once Covid eviction moratoriums are phased out.

But, due to a lack of standardization in eviction filings across the US, the Eviction Tracking System is currently available for only 11 cities, leaving many more places facing a high risk of eviction spikes out of the loop.

Each city included in the Eviction Tracking System shows rolling weekly and monthly eviction filing counts. A percent change is calculated by comparing current eviction filings to baseline eviction filings for a quick look at whether a city might be experiencing an uptick.

Timely US eviction data for a handful of cities is now available from the Eviction Lab. (Courtesy Eviction Lab)

The tracking system also provides a more detailed report on each city’s Covid eviction moratorium efforts and more granular geographic and demographic information on the city’s evictions.

Click to the above image to see a city-level eviction map, in this case for Pittsburgh. (Courtesy Eviction Lab)

As part of their Covid Resource, the Eviction Lab together with Columbia Law School professor Emily Benfer also compiled a scorecard for each US state that ranks Covid-related tenant protection measures. A total of 15 of the 50 US states plus Washington DC received a score of zero because those states provided little if any protections.

CityMetric talked with Peter Hepburn, an assistant professor at Rutgers who just finished a two-year postdoc at the Eviction Lab, and Jeff Reichman, principal at the data science research firm January Advisors, about the struggles involved in collecting and analysing eviction data across the US.

Perhaps the most notable hurdle both researchers addressed is that there’s no standardized reporting of evictions across jurisdictions. Most evictions are reported to county-level governments, however what “reporting” means differs among and even within each county. 

In Texas, evictions go through the Justice of the Peace Courts. In Virginia they’re processed by General District Courts. Judges in Milwaukee are sealing more eviction case documents that come through their courtroom. In Austin, Pittsburgh and Richmond, eviction addresses aren’t available online but ZIP codes are. In Denver you have to pay about $7 to access a single eviction filing. In Alabama*, it’s $10 per eviction filing. 

Once the filings are acquired, the next barrier is normalizing them. While some jurisdictions share reporting systems, many have different fields and formats. Some are digital, but many are images of text or handwritten documents that require optical character recognition programs and natural language processors in order to translate them into data. That, or the filings would have to be processed by hand. 

“There's not enough interns in the world to do that work,” says Hepburn.


Aggregating data from all of these sources and normalizing them requires knowledge of the nuances in each jurisdiction. “It would be nice if, for every region, we were looking for the exact same things,” says Reichman. “Instead, depending on the vendor that they use, and depending on how the data is made available, it's a puzzle for each one.”

In December of 2019, US Senators Michael Bennet of Colorado and Rob Portman of Ohio introduced a bill that would set up state and local grants aimed at reducing low-income evictions. Included in the bill is a measure to enhance data collection. Hepburn is hopeful that the bill could one day mean an easier job for those trying to analyse eviction data.

That said, Hepburn and Reichman caution against the public release of granular eviction data. 

“In a lot of cases, what this gets used for is for tenant screening services,” says Hepburn. “There are companies that go and collect these data and make them available to landlords to try to check and see if their potential tenants have been previously evicted, or even just filed against for eviction, without any sort of judgement.”

According to research by Eviction Lab principal Matthew Desmond and Tracey Shollenberger, who is now vice president of science at Harvard’s Center for Policing Equity, residents who have been evicted or even just filed against for eviction often have a much harder time finding equal-quality housing in the future. That coupled with evidence that evictions affect minority populations at disproportionate rates can lead to widening racial and economic gaps in neighborhoods.

While opening up raw data on evictions to the public would not be the best option, making timely, granular data available to researchers and government officials can improve the system’s ability to respond to potential eviction crises.

Data on current and historical evictions can help city officials spot trends in who is getting evicted and who is doing the evicting. It can help inform new housing policy and reform old housing policies that may put more vulnerable citizens at undue risk.

Hepburn says that the Eviction Lab is currently working, in part with the ACLU, on research that shows the extent to which Black renters are disproportionately affected by the eviction crisis.

More broadly, says Hepburn, better data can help provide some oversight for a system which is largely unregulated.

“It's the Wild West, right? There's no right to representation. Defendants have no right to counsel. They're on their own here,” says Hepburn. “I mean, this is people losing their homes, and they're being processed in bulk very quickly by the system that has very little oversight, and that we know very little about.”

A 2018 report by the Philadelphia Mayor’s Taskforce on Eviction Prevention and Response found that of Philadelphia’s 22,500 eviction cases in 2016, tenants had legal representation in only 9% of them.

Included in Hepburn’s eviction data wishlist is an additional ask, something that is rarely included in any of the filings that the Eviction Lab and January Advisors have been poring over for years. He wants to know the relationship between money owed and monthly rent.

“At the individual level, if you were found to owe $1,500, was that on an apartment that's $1,500 a month? Or was it an apartment that's $500 a month? Because that makes a big difference in the story you're telling about the nature of the crisis, right? If you're letting somebody get three months behind that's different than evicting them immediately once they fall behind,” Hepburn says.

Now that the Eviction Tracking System has been out for a week, Hepburn says one of the next steps is to start reaching out to state and local governments to see if they can garner interest in the project. While he’s not ready to name any names just yet, he says that they’re already involved in talks with some interested parties.

*Correction: This story initially misidentified a jurisdiction that charges $10 to access an eviction filing. It is the state of Alabama, not the city of Atlanta. Also, at the time of publication, Peter Hepburn was an assistant professor at Rutgers, not an associate professor.

Alexandra Kanik is a data reporter at CityMetric.