Protecting the Biodiverse Fabric of Nature – A MAHB Dialogue with Ana Luz Porzecanski, Director at the AMNH

Geoffrey Holland | November 17, 2022 | Leave a Comment

Geoff Holland – What is the current status of the natural world on planet Earth?

Ana Luz Porzecanski – The natural world, or whatever you choose to call the full biodiversity of life on Earth is declining at an unprecedented rate. The evidence for this is overwhelming. It was clear 20 years ago. Back in 2005, the Millennium Ecosystem Assessment looked at the century that had just ended and did a comprehensive evaluation. This assessment showed that over the second half of the 20th Century, humans had transformed Earth’s ecosystems more rapidly and more extensively than in any comparable period in human history. For example, among plants and vertebrates, the great majority of species were declining in distribution, abundance, or both. The observed rates of species extinction were 100 to 1000 times higher than the average rates for comparable groups in the fossil record. And in the future, these losses could increase by a factor of 100. And of course, key ecosystems are being degraded in their ability to support humans. This is true especially for wetlands, including rivers, lakes, saltwater marshes, and coastal systems including coral reefs, estuaries, mangroves, urbanized coasts, islands, and tropical forests. In fact, this assessment from 20 years ago reported that forests had effectively disappeared in 25 countries, and 30 additional countries had lost more than 90% of their former forest cover, including the United States.

Recently, we’ve had several updated assessments and reports. In 2019 and 2020, reports on the status of global biodiversity and ecosystem services were published by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) and the United Nations Convention on Biological Diversity. They found that biodiversity continues to decline at an unprecedented rate and that the pressures driving those declines are intensifying. This feeds back into the integrity of ecosystems because ecosystems are a rich tapestry of interconnected lifeforms. So, when you have declines in abundance or diversity, all of this leads to a loss of benefits that we get from nature, from climate regulation to water purification, to pollination. These are not perks; they are essential to our survival, our livelihoods, our economies, our health, and our well-being.

GH – What is biodiversity and why is it so important for protecting and preserving nature’s design?

AP – I’m not sure I understand the term nature’s design. But I think you’re referring to nature’s integrity, interrelationships, and interconnectedness. Now, different peoples and cultures have different ways of relating to nature. My view as a scientist is that biodiversity is the variety of lifeforms on Earth and the ecological and evolutionary processes that sustain life. Other people with other backgrounds may have different ways of defining biodiversity. I love this take by the Indigenous ecologist and writer, Robin Wall Kimmerer. She says “Biodiversity is the imagination of the Earth; the source of innovation and adaptation and evolution that enables the ongoing flourishing of life”. I love that. Whatever you call it, the biotic communities’ ecosystems have intrinsic value and a right to exist. They depend on each other, and therefore they’re important to each other independent of us. But of course, humans also depend profoundly on the rest of biodiversity. It underpins human life and healthy economies. Consider that 75% of our food crops– including fruits and vegetables, and some of our most important cash crops like coffee, almonds, and cocoa, rely fully on animal pollination. Our food security is backed by a stable climate, water cycling, healthy soil, and natural pollination. Our health depends on these ecological dynamics because they keep pests and diseases in check. I think this makes biodiversity loss and the biodiversity crisis, not just an ecological crisis, but also an ethical crisis. You could argue it’s a moral crisis, a human crisis, a health crisis, and an economic crisis. 

GH – The late, great biologist E.O. Wilson said, at the current level of only 15% of our Earth’s habitable land left undisturbed by humans, we could lose half of our planet’s biodiversity by the end of this century. Wilson called for action to preserve half of the Earth for nature. Do you agree with his assessment and his Half-Earth remedy?

AP – Let’s talk about that first statement in your question about only 15% of habitable land being undisturbed by humans. According to the World database on protected areas, as of May 2021, 16.5% of land and inland water ecosystems are officially recognized as protected areas or under other effective area-based conservation measures. So, I would say that 16 plus percent of land is under some type of human protection or management that mitigates biodiversity loss. In fact, probably hundreds of thousands of professionals and nature stewards do this work every day. So, I wouldn’t call that 16% undisturbed, I would call it actively protected or managed. And while it may seem a technicality to point out that this land is not undisturbed but managed, it is important, especially to the people who have been in those areas since time immemorial. In some cases, conservation has been used as a reason to move people forcefully away from those areas. I think when we talk about protection, we should be talking about the kinds of disturbances that are really detrimental to ecosystems and to people’s relationship with nature in that place, or the local cultural diversity. The challenges that come to mind for me are things like deforestation for industrial agriculture and extensive cattle ranching, coastal land development, industrial mining, dams, and roads. Those are the kinds of disturbances that I think we talk about when we say we want that land undisturbed. The other important thing to consider is that we have put ourselves in a position where some form of management is now necessary everywhere given the impacts of habitat loss, invasive species, and climate change. With pervasive influences like that, it makes more sense to actively manage land and wildlife, even what we would consider highly intact land, for resilience and persistence, not necessarily complete isolation from humans. We know that some people have been managing landscapes that we consider “intact” for millennia. There’s evidence that people have managed portions of tropical forests to enhance soil richness and plant diversity, or large landscapes for fire resilience.

It is true that in the last century or two, land management has generally not employed a long-term lens, but a near-sighted one. We have used an exploitative approach as if we could sustain infinite economic growth, and we’ve had ever-growing consumption despite rising inequality. So I wholeheartedly agree with E.O. Wilson on this point: Unless we change our approach, we will see unimaginable losses by the end of this century, and also massive human suffering. The Half-Earth initiative inspires us to think about bold action and ambitious goals. We do need to think big and be bold, and aim to change the status quo, but I find that incomplete as an agenda for action because it raises a lot of questions about implementation. For example, focusing on extensive coverage may lead to prioritizing quantity over quality. So, we may see expedient, “low-hanging fruit” strategies to reach a national goal or a global goal, but those strategies may not be the most effective in terms of what’s really needed for protection. And of course, perhaps most importantly, there are questions around sovereignty and inclusion that need to be carefully considered. Given what we know about what makes protection effective, the most effective conservation is led locally. So, if we are focusing on protection, I think we should be focusing more on how we’re protecting, how protection happens, and by whom, rather than how much. And we absolutely need to address the underlying drivers or root causes of the planet’s biodiversity loss– such as the view that we are separate from nature, the pursuit of ever-growing economic growth and consumption, and ineffective institutions– which is why protection became necessary in the first place. If we don’t address these issues, I don’t think we have a chance of mitigating biodiversity loss. We can’t protect everything everywhere, right? Yes, more protection is better, but the real question for me is not how much of the Earth we need to protect, but how we need to protect the whole Earth. More importantly, how do we change the way we live on this planet. The whole planet. That transformation is one that we need every sector of society involved in. It’s not just about conservation.

GH – There are now 8 billion humans on Earth with the number expected to reach 10-12 billion by the end of this century. What’s wrong with that picture?

AP – When I think about population, two things really concern me. First is that the 8 billion people living on the planet lead extremely unequal lives. Too many people are living in desperate, unacceptable poverty. There’s an unimaginable concentration of wealth and resources in the hands of very few people. The second thing is that our production and consumption have increased even faster than the population, and they show no sign of slowing down. And they are linked to highly inefficient and unsustainable practices. In the past 50 years, the growth of the human population has doubled, but the global economy has grown nearly fourfold, and global trade has grown tenfold. So yes, we have a growing population, but I would say the real problem is that a substantial part of that population is directly reliant on natural resources for daily needs but those people are unable to make decisions beyond the short term or plan for the future, including family planning. At the same time, another share of the population is demanding more and more from ecosystems in very nearsighted ways to grow their material well-being and accumulate wealth. This is a recipe for disaster because in neither of these scenarios are we using our natural resources rationally or sustainably. I think our attention should be placed on changing those two trends, extreme inequality, and increasing unsustainable production and consumption. If they change, we may be able to manage a growing population much more effectively, and the population is going to grow. I don’t see focusing on population numbers, alone, as a way to address the biodiversity and climate crisis effectively. We have to deal with some difficult moral questions, like who should reduce their birth rates. The good news is we can shape demographic change, for example, through the empowerment of people, and get multiple benefits. So, investing in the education of children, and particularly, empowerment of girls and women everywhere, including in developed countries like ours, is not only the best way to slow population growth but it’s also a climate solution and a human rights solution. Project Drawdown has quantified this as a climate solution, specifically in terms of gigatons of carbon that would be reduced. Fortunately, population growth is already slowing in the countries that demand the most from the planet, those that consume and emit the most. We need to place a lot of attention on transforming how we operate and grow our food systems, how we get our energy, how we move around, how we build our cities, and how we relate to and manage nature. We have few precious years to act, very little time. If our main focus is on reducing population growth, which is a complex problem, we’re not likely to see much change on that timescale. I think we should focus on some of the other challenges that I’ve mentioned. They directly reflect the impact human population numbers have on the planet.

GH – For thousands of years, human culture has been shaped by the assumption that we are above and superior to nature. How important is it for all of humanity to recognize we are part of nature and as such, we have a primary obligation to care for the natural world we all depend on? 

AP – This is a wonderful question and a very important question. First of all, I would argue that there is no such thing as human culture. So, when you say human culture has been shaped by this assumption that we’re superior, well, we are all part of humanity, we all share a human condition. But I don’t think we all share the same culture; there are myriad human cultures and different cultures have different ways of relating to nature. And it’s a really timely question. I don’t know if you saw the recent IPBES report or assessment that was just published after four years of work. It was from over 80 scientists from all over the world. They just released this massive assessment on exactly this question, which comes down to ‘What are the different ways in which humans value nature?’ Also, what role have these cultural differences played in the crisis that we face? And how can we harness these worthy cultural forces to move forward? 

The report identifies four broad categories or perspectives on nature. I’ll describe them. The first one is those cultures where people see themselves as living from nature. This perspective emphasizes that nature provides what we need such as food and material goods. The cultures where people take this perspective primarily see nature as separate, and often inferior to humans, something to dominate, to exploit. A second perspective is to see ourselves as living with nature. Those who adopt this perspective may see nature as separate but may seek coexistence or have a sense of stewardship for nature, a sense of responsibility. A third perspective is to see ourselves not as living from or with, but as living in nature. So, here nature is like the setting for your sense of place. It may be integral to your identity, and you have a sense of belonging to it.

And then finally, there’s living as nature, which captures the perspective of those cultures, typically Indigenous cultures, that see the natural world as part of a person’s very self, like part of their mental, physical, and spiritual being. They see themselves in total oneness with nature. For Indigenous cultures, non-human beings may be considered relatives or kin, or equals and sometimes equals in rights, as with rivers that may have rights just like we do. These different ways of relating to nature are important, as the authors of the report argue because too often decisions are made based on only a narrow set of those values, particularly market-based values of nature, such as when soil and ecosystems are seen primarily as places for intensive production of food. They don’t reflect fully how converting nature in this way can affect people’s quality of life in other ways. So, accounting is really important. In a place like the USA, you have a mix of all these cultural perspectives on nature. How do we move forward in this kind of pluralistic landscape? In the report, they compile more than 50 methods and approaches that can be used to establish values of nature that can be used in decision-making. I think this is all easier said than done. The big takeaway is that the way nature is valued in political and economic decisions is a key driver of the global biodiversity crisis. It’s also a vital opportunity; if we use more diverse values, we may change how decisions are made. So it’s very, very important.

GH – How much of the problem with shrinking biodiversity boils down to what we eat?

AP – I want to start by saying that this is not my area of expertise. I really learned a lot working closely with some colleagues here. I’d like to directly credit Erin Betley, and Eleanor Sterling, because they’ve done extensive work in this area. They curated an exhibition called ‘Our Global Kitchen’ that is all about this issue. I’ve learned from them that what we chose to eat is a big part of the problem. Our food is the most direct and visible contact we have with biodiversity; we’re putting biodiversity on our plates every day. Even for people who buy packaged food all the time, it’s still biodiversity on your plate. Our whole global food system has a massive impact. Decades of evidence have made clear that our agricultural systems degrade land, degrade water, degrade biodiversity, and drive climate change in ways that are interlinked and feed back into each other. Almost 40% of the planet’s ice-free or habitable terrestrial surface is devoted to agriculture today. This requires constant inputs like irrigation, synthetic fertilizers, and pesticides. Only about 60% of the food we produce feeds humans directly. Much of it is used for livestock or biofuels. Of all the food that is produced for humans, 40% is wasted along the supply chain. So, all those inputs, the water, the soil, the fertilizers, and the labor that went into producing that food is wasted as well. Our food system, as my colleagues like to point out, is designed for profit and calories, not health, or equity. And this is how on a planet of 8 billion people, no fewer than 1 billion are chronically undernourished. At the same time, millions have premature mortality due to diet-related diseases. Clearly, we’re producing enough calories to feed everyone, but we’re really failing, falling short, in terms of the equitable distribution of food. And of course, we’ve seen how vulnerable our food system is to disruption, and how globalized it is. With the pandemic, so many vulnerabilities were exposed. So, the flip side is that if you look at this as a system, and you look at all the inputs that go into the system, it really is a tremendous opportunity to address not only biodiversity and climate but also how we can become a more equitable and just society in general. There are many examples around the world of how to develop better food systems that respect the land, water, and biodiversity. There’s tremendous forward thinking being applied in this arena.

GH – If humanity fails to adequately address climate change, how will the natural world be impacted?

AP – This is a very troubling question. I went back to review the IPCC report that was published in 2018 – the one that explains what we can expect under two degrees of global warming above pre-industrial levels. It’s a very disturbing picture, but I think the clearest picture of what we can expect. We’re looking at regional changes in climate, including warming to extreme temperatures in many regions of our planet. The number of hot days will increase in most land regions, especially in the tropics. We’ll see increases in the frequency and amount of heavy precipitation, many more flooding events; increases in the frequency also of droughts in some regions, an increased risk of extreme weather events, as we’ve already seen, and significant sea level rise. Sea level rise will cause saltwater intrusion (which will compromise water supply systems in many places), flooding, and damaged infrastructure. This will continue well beyond the end of this century. The magnitude of it, the speed at which happens, depends on our emissions pathway. If we are responsible and take significant action, the rise in sea levels may be slow enough that we can adapt. If not, it could have disastrous consequences, particularly for small islands, low-lying coastal areas, and cities (where most of us live). We may see an ice-free Arctic Ocean in the summers, irreversible losses of marine ecosystems, species extinctions, and other biodiversity-related impacts like forest fires and the spread of invasive species, and because of all this, there will be massive risks to health, livelihoods, to food security, to water supply, to geopolitical security, and economic growth. This will especially affect disadvantaged and marginalized populations.

Now, I have described these consequences very calmly, and when you read these reports, the language is very precise and scientific, you don’t see any emotional statements. But really, let’s call it what it is: this is terrifying. This vision of the future is of an unprecedented catastrophe that none of us can really quite imagine, and it is happening in slow motion and affecting us all. A few years ago, we hosted a public lecture on climate change at the Museum, and someone from the audience came to me quietly afterward. He looked me in the eye and asked, ‘How many people are going to die?’ I had to admit to him there is likely to be massive suffering and death. But I don’t think it is likely that humans are going to disappear. It’s not going to be the end of humanity. What I hope is that we don’t lose our humanity and our capacity for empathy in the process. We must not ignore it. We can’t let it paralyze us because there’s much to save, and there’s much innovation now going on as well. So, to echo the language of the activists on the street, this is not a drill; our house is on fire. There is no planet B. We have to act now, while we have the opportunity to prevent the worst impacts.

GH – Cosmic visionaries tell us because we’re in the digital age, we are essentially connected together like a collective conscience. Is that a good thing for your message about planetary stewardship?

AP – This is a little bit out of my area of expertise. I am not sure if our greater connectivity is producing a collective consciousness. Not everybody is part of this connectivity, right? I believe that maybe 60% of the global population is connected to the Internet.

In addition, this digital ecosystem that we’re all connected to is much like any other ecosystem. It’s full of microhabitats, different communities having their own private conversations and interactions. Sometimes they act like echo chambers and not like collective unifiers. This greater connectivity has introduced both dangers and benefits. Some of my friends who work in that world say what people call web 2.0, the web that put social media in the hands of our children is a bit of a failure. We have to hope the next version will be better. I’m hoping for new kinds of connectivity that are hard to imagine now, completely new ways of doing business and regulating ourselves, new ways of governance, new, more inclusive political institutions, new ways of spreading ideas, new ways of learning and engaging in collective action. As connectivity continues to evolve, I hope the benefits outweigh the dangers. In our work, we’re trying to seize every opportunity to encourage the sustainability transformation that we need. 

GH – Let’s assume humanity chooses to make responsible planetary stewardship a cultural commitment. What are the big steps we must take to restore healthy biodiversity to our planet?

AP – If we can’t visualize it, we can’t move in that direction. So, this is a very important question. Given what we know about human history and human power dynamics, there’s probably zero chance for all of humanity to reach some sort of consensus or make a concerted choice around anything. But maybe this is my 20th Century mind talking. However, I do have hope. I think there is a possibility that really influential actors– powerful governments, powerful companies, powerful popular movements, or perhaps new kinds of actors we can’t even imagine today – may sway us rapidly and lead to change at scale. That gives me hope. You mentioned cultural commitment. I think speaking of cultural change is a great way to put it. It needs to be a cultural change, a change that all people find acceptable. We do need to take our dependence on biodiversity seriously and act as if our lives depend on it. That’s a human cultural challenge. What steps do we have to take to restore biodiversity? We can start by accelerating our transition to cleaner renewable energy technologies. We have to rethink our cultural power dynamics, to recalibrate our measures of prosperity and our financial flows to accelerate this transition. Our decision-makers need to fully acknowledge and take into account the contribution that nature makes in helping us avoid these worst-case climate scenarios, both in terms of mitigation and adaptation. We have to protect and restore ecosystems everywhere as part and parcel of how we grow our food, get our energy, move around, and how we build our cities. We must learn to be wise and regenerative in all our human activities.

GH – Given what you know about the human cultural trends at play, where do you see us in our relationship with nature ten, fifty, a hundred years from now?

AP – I always say scientists are not trained to imagine. That’s why we need to work with artists and the humanities. The 10-year mark is the hardest for me to predict and think about because of climate impacts, and also the really complex political dynamics at play right now, all around the world. The one thing I can predict about 10 years from now is that because of climate change, we will have found a whole new level of fear or respect, and hopefully reverence for nature. What we’re going to see in the next 10 years is really going to scare us. But I am a bit of an optimist at heart. You have to be to work in this field. I’m a humanist at heart as well. I have faith in people. So, I’m actually hopeful that we will evolve, and that our relationship with nature 50 to 100 years from now will be better. For example, this idea of herd immunity; we’ve all heard about it now because of the COVID-19 pandemic. Well, we can build more permanent herd immunity, make ourselves more resilient and immune to future pandemics, and also more resilient in the face of the worst climate disasters, if we invest in our environment, in social issues, and in fostering economic equality. I hope in 50 to 100 years, we’ll understand that all of these things are connected. We can choose to become smarter about how we use resources and land and energy. And hopefully, we’ll have adopted more holistic and inclusive economic paradigms that recognize the limits of our planet’s ability to provide. We need to encourage policy decisions based on the true costs for nature and people, and based on the impacts on future generations. I think our ways of doing things today will seem so backward to those who are here 50 to 100 years from now. They’re going to look at the way we relied on gas-powered cars and planes, at how we covered our cities in concrete, and how we wasted 40% of our food, and wonder what humans in our era were thinking.

Dr. Ana Luz Porzecanski grew up in Latin America in a family of European immigrants that nurtured a love of nature and culture, a deep curiosity about the workings of society, and a strong commitment to social justice. She studied evolutionary biology first in Uruguay and later at Columbia University in New York City, where she lives with her husband and daughters. Ana’s work has focused on understanding biodiversity and sustaining it for the future through research, evidence-based management, and education and capacity development. Building on collaborative and systems approaches, she has worked alongside local partners in over ten countries ranging from Cuba to Madagascar. She currently directs the Center for Biodiversity and Conservation at the American Museum of Natural History, which aims to bring strong evidence from multiple sources and perspectives to bear on complex conservation problems and foster collaboration on robust and equitable solutions.

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