Earth’s nature is being ravaged by population growth

By Malte Andersson and Frank Götmark | 16 January 2024
The Overpopulation Project


Humanity’s rapid expansion leads to environmental destruction, starvation and ravaged biodiversity. Population growth needs to be ended as soon as possible for sustainability.

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 billion and are now growing by about 80 million a year. At the same time species and ecosystems are declining and disappearing through our overexploitation: more than one in four of 150,000 reviewed species are threatened, half of which are vascular plants. Among 71,000 animal species studied, almost half are decreasing, only 3 percent are increasing. And it goes fast. Since 1970, populations of mammals, birds, amphibians, reptiles and fish have declined on average about 70 percent. The reasons are many. Overexploitation in forestry, hunting and fishing. Agriculture and livestock farming over expanding areas. Infrastructure and buildings such as housing, industries, roads and mines. Our spread of invasive organisms.

Species usually decline because we take over and wipe out their habitats – natural ecosystems and environments to which they have long adapted through evolution. These days habitat destruction happens mainly in the tropics, but also in Europe. There, plants and animals are decreasing in parallel with increasing population density and consumption, as the ecologist Trevor Beebee shows in his current book “Impacts of Human Population on Wildlife” (2023).

Another threat to biological diversity is climate change, its two main driving forces being increasing population and consumption, according to the IPCC’s major report of 2022. The rich world’s high consumption of course needs to be reduced, which is often highlighted in the environmental debate (see for example, Sustainable consumption). On the other hand, the extremely destructive consequences of population growth for biological diversity and sustainability are rarely or never discussed, whether by media such as SR or SVT, by politicians, the UN or the environmental movement (for example WWF and the Nature Conservation Association). Has the topic become taboo?

In 2017, thousands of international researchers pointed out in a “Scientists’ Warning to Humanity” the need to stabilize our population. And in his substantial overview, Beebee (2023) shows that “overpopulation is at least as much a rich as a poor country problem”. Efforts are required from all countries. A new report shows that we have wiped out most of the Earth’s large land mammals, reducing them to a tiny fraction of the richness before our increased accelerated (through fossil energy, medical advances, better food and longer life). In biomass we now completely dominate among the Earth’s remaining land mammals (see figure). Is our massive expansion, to the detriment of other species, ethically justified?

We make up 390 million tons and our domesticated mammals – cows, pigs, sheep and companion animals such as horses, dogs and more – 630 million tons. A total of just over a billion tons, fifty times more than all the world’s remaining wild land mammals, which we have reduced to a mere 20 million tons. See graph below!

The current biomass of mammals on Earth: people 390 million tons, our domesticated mammals 630 million tons, and remaining wild terrestrial mammals, 20 million tons. Source: Greenspoon et al., “The global biomass of wild mammals” (2023), data from 2019. Graphics from Svenska Dagbladet: Thomas Molén

A few thousand years ago, before we became farmers, the proportions were more than reversed. We were only a few million people, less than a thousandth of today’s population, and had no livestock.

In parts of Western Asia and especially in Africa, where the population is expected to grow by 2.5 billion by 2088 according to the UN, birth rates remain high. The number of malnourished in Africa is now close to 300 million and increases every year according to the FAO. Population growth is about to lead to disaster for both Africa’s people and its biodiversity. Hundreds of millions of women lack contraception, and social norms influenced by patriarchy, religion and ethnic competition favor many children.

Despite the negative consequences of the huge population increases, there is no population target among the UN’s 17 sustainable development goals of 2030. But independent researchers point out that an ecologically sustainable population is rather around 2-3 billion rather than the 10.4 we are heading towards according to the UN. If everyone is to reach European standards of living, a sustainable human world population probably cannot exceed about 3 billion. Even less if the conditions of other species are to be improved. The UN Conference on Biodiversity, COP15, proposed last year the protection of 30 percent of the planet for biodiversity, and the recent UN Conference in Nairobi proposed concrete measures to address the needs identified at COP15.

As we explained in SvD 23/10 2022, countries with high birth rates need to lower them significantly to contribute to a sustainable world population. On a positive note, voluntary programs for family planning in, for example, Bangladesh, Thailand and South Korea have worked well and rapidly lowered birth rates. Unfortunately, many programs for family planning disappeared after 1995, when SRHR (Sexual and Reproductive Health and Rights) replaced fertility reduction as the focus for family planning programs, also in Swedish aid programs. But research shows that longer education for sub-Saharan girls substantially increases contraceptive use only if it is combined with family planning programs.

Overall, there is strong evidence for the importance of aid to both family planning and SRHR and women’s empowerment and education. The right to education in family planning was emphasized by the UN as early as 1968. When the government now reconsiders Swedish aid, it can learn from previous mistakes and provide much-needed support for both SRHR and family planning programs. Especially new programs that also take the environment and nature into account and increase the possibility of preserving the Earth’s biological diversity.

Malte Andersson
ecologist, professor emeritus, University of Gothenburg, Sweden

Frank Götmark
professor of ecology and nature conservation, University of Gothenburg, Sweden

Reprinted with permission from Frank Götmark – Project leader of The Overpopulation Project (TORP); Professor, Animal ecology and Conservation Biology, University of Gothenburg.

An Integrated Climate Change Response: The Role of Population

Earth currently experiencing a sixth mass extinction, according to scientists | 60 Minutes

Why Overpopulation is Actually a Problem

Sir David Attenborough on overpopulation

Be sure to ‘like’ us on Facebook


Please enter your comment!
Please enter your name here