
TOP – Research and Outreach
Too many people consuming too much
Distinguishing ecologically sustainable from excessive human populations is necessary to understand humanity’s environmental challenges and pursue our best options for addressing them. A new publication from TOP presents a definition of human overpopulation based on plausible scientific and ethical criteria, rather than wishful thinking. by Philip Cafaro Last year, TOP published a working paper presenting…
With a population nearing 70 million, the UK is feeling the pressure on the housing and job markets. Stabilising the population would ease this pressure, giving more people access to affordable housing and strengthening wages, utlimately raising the quality of life for UK citizens. by R. M. Smilie Introduction The United Kingdom (UK) has rarely…
Immigration will be the key factor determining whether populations in the developed world increase or decrease over the coming century. Newly published policy-based population projections illustrate this for the United States. by Philip Cafaro Population size helps determine human societies’ environmental impacts. Given that immigration is a key factor influencing the size of human populations,…
In the 1970’s the leading intellectuals in the United States were concerned about overpopulation. Fifty years later, the best and brightest minds in America now think we are running out of people. What the hell is going on? by Brad Meiklejohn “Growth for the sake of growth is the ideology of the cancer cell.” –…
Daniel Lee Carrigan, founder of the GAIA Earth-Balance Foundation, died on 4 March 2024 after a long struggle with heart disease. We gratefully commemorate his contribution to population and sustainability efforts. by Jane O’Sullivan Like a shooting star, Dan Carrigan’s dynamic energy lit up the population-sustainability world for a brief few years. In its wake,…
Humanity’s rapid expansion leads to environmental destruction, starvation and ravaged biodiversity. Population growth needs to be ended as soon as possible for sustainability. By Malte Andersson and Frank Götmark Published 2024-01-02 in Svenska Dagbladet, morning newspaper in Sweden (translated by TOP) In 1800, the world’s population was 1 billion, but in 2022 we exceeded 8…
With humanity currently in overshoot, societal changes must be enacted to return to sustainable levels. While either a country’s ecological footprint or population size could be altered to achieve the necessary level, combined efforts on both fronts would be most effective. By Denis Garnier, president of Démographie Responsable A sustainable population corresponds to the total…
To avoid disastrous deterioration of Earth’s climate and biosphere, humanity has to reduce its demands on nature. Fewer births and a falling population is no quick fix, but compared with voluntary austerity, it has many more up-sides than down-sides. by Jon Austen Scientists are reporting that there is an existential threat to life on Earth.…
People in rich countries must rein in their consumption, but the hypocrisy of high-profile environment advocates makes them poor role models, argues Gaia Baracetti. By Gaia Baracetti This is an overpopulation blog, but its authors have made it clear that overconsumption is a problem too, and that the two are, as it is often said,…
On 2 August, humanity will have used up its quota of renewable resources for 2023, according to Ecological Footprint analyses. But this barely scratches the surface of understanding the overshoot predicament we now face. By Jane O’Sullivan Earth Overshoot Day falls on 2 August this year. This is the day on which, according to the…
Low birth rates are often regarded as problematic by major media, which overlook the perils of population increase. Here we show that unsustainable long-term population growth prevails in developing countries, despite historical family planning and gradually sinking birth rates. One lesson is that further reduced rates are urgently needed in high-fertility countries, in Africa and…
Another UN World Population Day passed with the UN focussing on anything but population growth. Australia’s population is growing faster than most, with sustainability not on the government’s radar, as Stephen Williams laments. By Stephen Williams I don’t pay much attention to awareness days, but I make an exception for World Population Day, first observed…
In 2020 and 2021, I recorded two seasons of the TV show The Population Factor. Each episode features in-depth conversations focused on a particular aspect of the population/environment connection. Check out seasons one (hour-long episodes) and two (half-hour episodes), all available for free streaming at the links below. by Phil Cafaro Season 1 Episode 1.…
These islands were more-or-less isolated, microcosms that perhaps tell us what is going to happen with the global population. Anthropological accounts also describe remarkable forms of birth control. Do they tell us anything about how to achieve sustainable populations today? By Frank Götmark Easter Island, and historical background One of the most debated questions…
At the end of 2022, the Wittgenstein Centre for Demography and Human Capital held a conference titled Population and Climate Change: The Defining Relationship of the 21st Century. Yet as one participant noted, in this presentation from the conference, the desire to downplay population’s importance is hard to avoid, even among those who should know…
Anthropocentrism is preventing humanity from dealing with the world’s cascading environmental crises. Stephen Williams reviews the work of Catholic historian Paul Collins who argues depopulation is an urgent moral imperative. By Stephen Williams A new discussion paper on population ethics written by Catholic historian Paul Collins is as radical as it is worthy. The paper…
On 15 November 2022, Earth’s human population will pass 8 Billion, according to estimates by the United Nations. This sobering milestone should galvanise us to redouble our efforts to minimise further growth. By Valorie M. Allen I have found myself checking out the population counter on my website more and more often as it approaches…
For those times when we feel worn down by the thanklessness of campaigning for population sustainability, it can be uplifting to hear the voices of veteran campaigners whose courage has never wavered. Michael Bayliss introduces us to a conversation to inspire. by Michael Bayliss In the most recent episode of Post-Growth Australia Podcast (PGAP) I…
Here at TOP, we are often asked how we define overpopulation and whether it’s a helpful concept. Good questions! Below I propose a definition of overpopulation, after first considering the suggestion that it’s not necessary or helpful to deploy the term, even —or especially! — if we want to convince our societies to accept good…
The concept of optimum population size is nothing new, but in recent decades the methodology used to calculate it has seen little development. In a recently published book, We Zijn Met Te Veel (Dutch for We Are Too Many), a new approach is proposed for calculating optimum population size. by Fons Jena In the available literature…
One of the biggest obstacles to addressing overpopulation is the ignorance and timidity of most environmental funders regarding population issues. So we were happy to recently come across the following text on the website of the Colcom Foundation, a major environmental foundation out of Pittsburgh, Pennsylvania, USA. Particularly welcome are the direct links they draw…
A recent book introduces a new approach to the science of overpopulation. We Zijn Met Te Veel (Dutch for We Are Too Many) explores a new theoretical foundation for the concept of overpopulation and explains why a smaller human population is a necessary – but not sufficient – condition for a more hospitable world. by…
Graphic media coverage of the current hunger in southern Madagascar is not wasting the opportunity to advocate climate justice. But nobody mentions there are now seven Madagascan mouths to feed for each one present in 1950. This denialism is not in the interests of the hungry, nor Madagascar’s disappearing wildlife, argues Madeline Weld. By Madeline…
After three decades of neglect, more environmentalists are waking back up to the need to limit human numbers. But like Rip Van Winkle, we find that the world changed while we were asleep. There are now billions more people, consuming more than ever, while our world has grown warmer, tamer, and more polluted. A new…
A recent TEDx talk delves into our species’ reverence for economic and population growth, which is pushing us – and the natural world – outside our safe operating space. In ‘Limits to Sustainability’, João Abegão attempts to communicate the expanding footprint of our species by comparing it with transformations suffered by past complex societies. By…
Human population grows, Earth doesn’t. A certain environmental impact is needed to satisfy basic human needs. When multiplied by a huge population, even a small average individual impact can become high, overshooting planetary boundaries. Achieving both environmental sustainability and high human development is hence a challenge. Can we win this challenge without considering the population…
Demographic changes are not immediate, but rather take a long time to happen. In an article originally posted in The Ecological Citizen, Joe Bish argues that the population discussion needs to be reframed as an imperative to achieving a long-term sustainable civilisation, rather than an overriding priority for near term goals. By Joe Bish The…
The mainstream media rarely report about the role of population growth in environmental and climate disruptions, but the Op-Ed below was actually published in the high-circulating Swedish Social Democratic newspaper Aftonbladet a week ago. The original Swedish text is available here. The article gives a broad overview, ending with an unusual suggestion. There were 250…
A group of distinguished scientists have called for rapid action to reverse unsustainable population growth as threats to global ecological boundaries become more apparent. The evidence was set out at an online conference organised by Scientists Warning Europe to mark this year’s World Population Day. by Brian McGavin With the human ecological footprint already 170…
A frequent assumption in population policy debates is that stabilizing populations will be sufficient to achieve ecological sustainability. But as Karin Kuhlemann observes, “that a population’s size is stable in no way entails sustainability. It may be sustainable, or it may be far too large.” A recent book from philosopher Trevor Hedberg convincingly argues the…
A new initiative aims to draw attention to stories about population and consumption from women around the world to mark World Population Day. The focus lies on personal experiences and encourages a greater discussion about the links between population, consumption, and protecting nature. By Pernilla Hansson World Population Day is held every year on the…
In its recent report State of World Population 2021 the United Nations Population Fund (UNFPA) highlights bodily autonomy as a universal right. Of course, nobody in a civilised society would object against this position. However, by limiting the notion to the domain of gender-based violence and harmful practices such as child marriage, female genital mutilation,…
A recently published article asked European demographers about their attitudes towards climate change and population growth. It shows that while most demographers are in agreement on the need to act on climate change, the effect of population growth is largely not understood. By The Overpopulation Project An article published in March this year in the…
After decades of silence, the International Union for the Conservation of Nature has passed a motion reaffirming the importance of addressing population matters to achieving conservation success. This continues a welcome recent trend among conservation scientists to speak up about the potential benefits of reining in population growth. by Pernilla Hansson The International Union for…
Efforts to specify the optimal human population on Earth are as complex as they are controversial. A recent book from Cambridge University economist Sir Partha Dasgupta develops a theoretically rigorous approach to this perennial question, finding that an optimal human population might range from 500 million to 5 billion. by Philip Cafaro It is gratifying…
After months in the works, a new television program devoted to exploring all aspects of the population / environment connection is now streaming free on demand. Dallas-based EarthX TV hosts The Population Factor, whose first episode features an interview with environmental legend Paul Ehrlich. Two other episodes follow: one about the challenges of limiting climate…
A robust account of human responsibility, applied to humanity’s economic and demographic decisions, is the missing link in environmentalists’ endeavors to save our planet. Contemporary humanity has been misled by promises of rights without responsibilities, win/win solutions, and individual success without discipline or concern for the common good. “Back to basics” should be our battle…
Imagine there’s no countries. It isn’t hard to do. Serving our corporate masters. And pasting smiles on our faces, too … Or better yet, imagine a world where citizens control their own destinies, within a peaceful and environmentally sustainable international order. That’s the real way forward. by the Honorable Kelvin Thomson I am a big…
































