The Technosphere and Human Population in the Anthropocene

Human population growth in the Anthropocene is striking: from 2.5 billion in 1950 to more than 8.3 billion now, a more than threefold increase in just 75 years. It had taken 150 years to reach 2.5 billion from the 1-billion mark, which had previously taken 300,000 years for Homo sapiens to reach. Population is clearly a key factor in the far-reaching Earth system changes that are making the Anthropocene Earth different from that of the Holocene. But population is intimately tied to other factors. The relationship between population and planetary transformation is complex, whether considered through scientific or social lenses. Here, we frame population growth in relation to the growth of the technosphere, the combined output of all human creations, since the mid-twentieth century. As the enhanced power of the technosphere brought advances in agriculture, health, communications, education, and much else, the human population grew not because people were having more babies, but because many more babies lived and life expectancy lengthened. There has been a “great escape” from grinding poverty and early death, but one that has also resulted in unprecedented levels of inequality and environmental degradation (Deaton 2014). 

One can compare population growth with other parameters, such as energy (Syvitski et al. 2020). Global human energy use rose from about 100 exajoules per year (1 exajoule being equal to 1 quintillion joules) in 1950 to about 630 exajoules per year now, a rate of increase almost double that of population growth overall. On the Anthropocene Earth, there are many more humans, and they are overall more energy-demanding. More than 80 percent of that energy came from burning fossil fuels, an unwanted consequence being the sharp rise in atmospheric carbon dioxide levels and the resulting global heating. 

The rapid rise in human population was also enabled by a supercharge in agricultural production, as new, high-yield crop varieties were developed in tandem with a massive increase in fertilizer use. Fixation of atmospheric nitrogen to form ammonia grew from about 2 million tons/year in 1950 to about 175 million tons/year today, a more than eighty-five fold increase, while phosphate rock production grew from about 9 million tons/year in 1950 to about 240 million tons/year today, a more than twenty-five-fold rise. These huge increases, orders of magnitude greater than the threefold rise in human population, more than doubled levels of phosphorus and reactive nitrogen at the Earth’s surface. They reflect the effort necessary to keep human population levels high above anything that might be considered our planet’s “normal” carrying capacity. Unwanted spinoffs here include the creation of widespread “dead zones” in lakes and coastal seas. 

This rise in agricultural production has been accompanied by a growing cultural preference for eating meat, which has increased crop production (due to energy losses along this longer food chain) and drastically altered terrestrial animal assemblages. Terrestrial mammal biomass is now mostly divided between humans (about 33 percent) and domesticated animals (about 65 percent); wild animals now comprise just two percent (Greenspoon et al. 2023). Similarly, two-thirds of all bird biomass is now made up of the standard supermarket (broiler) chicken, a short-lived technological construct unable to survive in the wild (Bennett et al. 2018; see also Nally, this volume). 

Population growth has acted like a ratchet on other pressures on the planet. As agriculture became more intensive and mechanized, the growing human population congregated in cities. The number of megacities (those with more than 10 million inhabitants) has grown from two in 1950 to over forty today, about a twentyfold increase. As cities have grown, there has been a surge in demand for the materials used to build them. In the Anthropocene, the dominant construction material is concrete, its use growing from about a billion tons a year in 1950 to about 30 billion tons a year today (Syvitski et al. 2020), again, proportionately far outpacing the growth in human numbers.

Population and Technofossil Diversity

Increasingly, more humans concentrated in cities as mechanized agriculture required less human labor. People could therefore be employed to devise and manufacture new materials and goods, turning the quantitative acceleration of the Anthropocene into a qualitative one to grow a new kind of diversity. A fundamental diversification—from a planet’s perspective, at least—is that of mineral composition. For about 2.5 billion years, Earth has possessed a little over 5,000 different minerals (Hazen et al. 2008). Then, over the Holocene, human ingenuity slowly, fitfully, created new mineral combinations, most obviously through metal smelting. This process acceleratedin the factories of the Industrial Revolution. By the mid-twentieth century, a couple of thousand more had been added (Behrens and Luksch 2006). Then came an explosion of diversification in these synthetic “minerals” in post-World War II materials science laboratories, which has increased their number to more than 300,000 (Hazen et al. 2017, updated). Some, such as steel and aluminum, are now common on a planetary scale. 

Novel synthetic organic compounds are also proliferating. The synthetic plastics industry has grown enormously since the mid-twentieth century, producing cheap, tough, decay-proof, malleable materials that are ubiquitous and almost infinitely protean in their range of applications. Plastics support longer, healthier human lives through myriad applications to food, medicine, water systems, communication/transport, and much else. But “as plastics degrade, they release hazardous compounds such as bisphenol A (BPA), dioxins, phthalates, furans, and heavy metals—substances linked to respiratory illnesses, endocrine disruption, and cancer. And the buildup of microplastics in agricultural soils and in our own bodies is quickly developing into a major public health threat” (Landrigan et al. 2025).

The mid-twentieth-century acceleration of the human population coincided with a greater capacity of that increased population to leave a long-term geological legacy. Clothes, for instance, throughout all previous human history, were time-consuming and expensive to make out of natural materials such as wool, cotton, and leather. These degraded quickly after use, so that archaeological finds of garments are rare. Now, mass-manufactured clothes (mostly made from synthetic plastics such as polyester) are cheap enough to be widely available to people of all incomes and—as a sudden planetary novelty— highly resistant to decay and so able to persist, when discarded, over geological timescales (Gabbott and Zalasiewicz 2025). The real significance for us is that these growing mountains of discarded plastic-based clothes (and all the other plastic items that we use) will persist on the shorter timescales that are significant to us. They represent forms of pollution that—in soils, river and marine sediments, and countless landfill sites—will make the lives of many future human generations more problematic, dangerous, and unpleasant. 

Plastics are but one example. A plethora of novel materials and objects has been produced through the combination of many industrious, inventive people released from the need to tend crops and animals, growing energy/material supplies, rapidly evolving technological possibilities, economic levers such as widely available credit, and a nearly universal commitment to growth as the measure of success. These served immediate purposes, but often quickly led to troubling consequences and geologically long-lasting repercussions. Pesticides, a boon that banished disease-carrying, crop-eating insects, also built up to harmful levels more widely in the biosphere. Fluorocarbon compounds, seemingly inert and wonderfully useful as fire retardants and in many other applications, turned out to have toxic effects and to be environmentally persistent. The silicon-based technologies that have come to underpin our world in just a few decades are resource- and energy-intensive. The uniquely large human population of the first decades of the Anthropocene is, in many cases, uniquely healthy and long-lived because of antibiotics, which quickly led to new microbial assemblages with antibiotic resistance, not only within medical settings, but widely across the global environment (Harper 2021). 

Population and the Technosphere

These inventions, with their manifest uses (identified early) and problems (discovered only later), are not discrete phenomena that somehow sprang up individually in modern times. Rather, they are expressions of a singular new development of the Earth system that, if not absolutely dependent on a billions-strong human population, has been greatly amplified and sped up by it. This is the technosphere, as conceptualized by Peter Haff (2014, 2019 and 2023). The technosphere is not simply the sum of all our technological creations (which now have a functional mass of over a trillion tons, overtaking the mass of the biosphere a few years ago [Elhacham et al. 2020]). Rather, it is a system made up of all that and of the human components (international bodies, governments, schools, companies, agricultural, industrial and white-collar workers, consumers, etc.) bound up within it. These human components are both the motor of the technosphere and utterly dependent upon it to exist in anything like our current numbers. In other words, we cannot think of today’s human population as separate from the technosphere. Our numbers rose with the technosphere’s rising power.

People do not consciously direct this overall system in any planned, meaningful way, because it is emergent, meaning that it was created by no one and develops without any entity’s governing powers, and also because our survival depends on it, so that just supporting our lives every day contributes to it. Unlike earlier extractive operations in the Holocene, the technosphere operates beyond our institutions’ control, regardless of our will. Its autonomy is partly due to the human enterprise being too fractured into competing, often warring, parts to enable such control (though certain human components, such as leaders of multinational companies, have greater influence on the nature, direction, and scale of its evolution). The technosphere’s independence is also due to its integrated complexity and magnitude. It is too enormous to manage, and we are so dependent upon it that altering any component is difficult and may put vital systems at risk. The current rapid, little-regulated development of AI exemplifies the technosphere’s considerable autonomy, which in turn speaks to our altered and limited political capacities. 

That technosphere’s future will determine the future of the human population. It, and the previously impossibly large human population that grew with it, are highly immature features of the Earth system. It operates in stark contrast to the biosphere, which is highly mature, honed by billions of years of coadaptation and coevolution, characterized by long-term stability and diversity and subsisting almost entirely upon solar energy. The biosphere recycles almost all of its materials. This maturity has made it resilient; it has endured at least five major extinction events and still survived. On the other hand, the technosphere, along with its human dependents, is precarious. Caught up in its own dynamics, it “races ahead like a forest fire” (Haff 2019), drawing down on nonrenewable fossil energy sources and other forms of nonrenewable natural capital such as a rich biosphere, soil, water, and minerals while recycling only a small fraction of the material it uses. Its functional mass is now outweighed, by an order of magnitude, by its own waste materials. The consequences are climate change, toxic pollution, biosphere degradation, and resource exhaustion that we see today. Both people and the technosphere we rely on are vulnerable. 

Framing the human population and the technosphere together clarifies the challenge of human survival in the Anthropocene. In the late Holocene, the question of population was often framed as an issue of numbers in relation to largely renewable resources. More people would need more resources; fewer people, fewer. Resources provided by the biosphere, hydrosphere, and soil would eventually replenish themselves if fewer human demands were made. Thomas Malthus (1766–1834) worried that the population was growing exponentially, outstripping agriculture’s abilities to keep up, and that famine would result. His insistence that human population size was constrained (as it still is within wild populations) by resource availability was seen as an attack on progressive Enlightenment thinkers such as William Godwin and Mary Wollstonecraft in London and Tom Paine in America. As Malthus expanded his thesis in the second edition of An Essay on the Principle of Population (1803), he considered the fate of Indigenous agrarian peoples in America and Australia, foreseeing the dangers of a planet inhabited and cultivated everywhere by human beings (Bashford and Chaplin 2016). His counsel was restraint. Decreasing the population would allow the lands’ resources—including nitrogen-depleted soils—to regenerate and support not vast numbers of impoverished, hungry toilers, but fewer inhabitants secure from precarity. For the Holocene Earth system, it made sense to think of a seesaw between regenerative natural resources and human demands. 

Discussion of population is still often framed in terms of numbers in relation to resources, but Malthus’s arithmetic applied to the planetary system of his time. In the Anthropocene, human numbers must be considered in relation to human dependence on the technosphere and a destabilized Earth system, one no longer capable of easy regeneration. Numbers still matter ethically: people must be provided for, and suffering must be avoided, especially among the most vulnerable. However, the seesaw between nature and human numbers no longer pertains. 

On the Anthropocene Earth, the addition of about 2 billion more people by century’s end (UNDESA 2022) will continue to draw down nonregenerative resources, while the technosphere’s relentless pursuit of materials and energy will produce ever more unrecycled waste. But the converse is no longer true. Fertility decline, already underway around the world, will not return us to the Holocene bounty. In some cases, it may even undermine the biodiversity that developed within formerly human-dominated ecosystems. For instance, the depopulated countryside of Japan has lost ecosystems known as satoyama at the edges of fields, which created a mosaic of ecosystems supporting diverse species; reforestation eliminates these areas and the species they supported. After the human population peaks globally sometime toward the end of the century, there is no reason to hope that biodiversity, water cycles, and soil health will return to Holocene conditions, for “the reality is that globally, the Holocene biosphere is gone, and the Anthropocene biosphere has arrived” (Barnosky and Hadly 2026). 

A declining population, too, may erode the technosphere’s capacity to supply human needs. Modern political, economic, and social systems are predicated on population growth, where younger generations support ageing generations, and on economic systems that return on investment; population decline thus creates financial challenges. Debt has reached new heights to cover the costs of public health care, retirement schemes, and other social amenities created when populations and economies were growing (e.g., in Japan and Italy). With fewer younger workers, maintaining this infrastructure and these services will be difficult. 

Meanwhile, labor and multifactor productivity (MFP) growth rates have been declining for several decades in advanced economies, and since 2007, MFP growth has flatlined in both advanced and emerging economies. The reason, posits Canadian economist Christina Caron, is that natural capital, defined as the organic and inorganic systems that underpin the global economy, is failing and has become a “limiting factor in the global economy” (Caron 2025). 

Because natural capital is not factored into standard economic equations, its loss is largely invisible. The clean air, rich soil, biodiversity, and a predictable climate necessary to the technosphere are dwindling already, even as much of the global population is still in want. In other words, both population growth and population decline present novel, intricate challenges in the Anthropocene. 

There is a tendency to avoid mentioning population. For instance, a recent essay titled the “Green Doughnut” argues that we should stay within planetary boundaries while ending social deprivation, an indisputably worthy goal (Fanning and Raworth 2025). However, these authors measure social shortfall and planetary overshoot without reference to population growth. They show, for instance, that at least 2 billion people still fall short according to most indicators without considering that from 2000 to 2022, the human population grew by almost 2 billion. Including population figures changes the calculation. 

Recognizing that the global challenge can be understood only in relation to population size, other degrowth economists include population in their analysis of the difficulty of attaining a decent life for all. For instance, currently, “no country meets basic needs for its citizens at a globally sustainable level of resource use,” and as the population rises to “11.2 billion by 2100,” as it was projected to do in 2018, “the challenge will be even greater.” The Green Doughnut, in which social needs are met and planetary boundaries are not overrun, they suggest, “could be a vanishing thin ring” (O’Neill et al. 2018). This thin ring, if it exists at all, is where we might hope to dwell in the future, but getting there will require a firm grasp on the essential factors involved, including population size and our reliance on the technosphere. 

So far, we have described the current human population and the technosphere as codependent, growing explosively since the mid-twentieth century. The dangers and precarity of this added Earth sphere are also clear. The essential political conundrum is that this sphere has a degree of autonomy beyond the powers of our governments and societies to control. However, it is possible to influence it and perhaps, ultimately, to stabilize it as part of a habitable Anthropocene Earth system. 

Perhaps the most overlooked means of working toward a mature and stabilized technosphere is promoting greater economic and social equality. Evidence shows that even the affluent enjoy a better quality of life in more equal countries—and that natural resource demand drops once excess, status-related consumption is no longer a priority. Creating greater equality among nations, too, would help limit social deprivation and resource demands, but will also be exceedingly difficult to negotiate, because “as poorer countries raise their material standards, the rich will have to lower theirs” (Wilkinson and Pickett 2024). As Duncan Kelly (2019) suggests, it is unlikely that we can achieve this aim through the “thin democracies,” defined simply by the right to vote. Only more equal societies with richer forms of democracy can address the value-laden issue of global well-being in the Anthropocene as we seek a tentative foothold on the narrow green ring of decency and resilience. Efforts to limit consumer demand for status products such as meat and private jets can be effective only if framed through an understanding of our dependence on the technosphere and its destabilization of the Earth system. 

Meeting the needs this century of both growing and declining populations in relation to the ravenous technosphere without further undermining Earth’shabitability is an unprecedented challenge. Trying to resolve our predicament while avoiding a planet-scale system failure will need a better appreciation of its dynamics from an Earth system perspective—a very new perspective for humans—and a stronger understanding of the indivisible links among population, the extractive technosphere, and planet-ary transformation. These three factors are best framed together as we come to terms with the Anthropocene. It’s a tall order, but it is literally a vital one.