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Overpopulation, climate crisis could overwhelm us
Author: Mark Tomlinson
Published: 09/07/2020

On Saturday 11 July, we'll observe World Population Day. In an opinion piece for Daily Maverick (6 July), Prof Mark Tomlinson (Institute for Life Course Health Research) writes that we need to act now to avoid being overwhelmed by overpopulation and the climate crisis.

  • Read the article below or click here for the piece as published.

What does COVID-19 have to do with World Population Day?

Mark Tomlinson

In 1989, the United Nations established World Population Day which is observed on 11 July every year. The choice of 11 July was prompted by a milestone  ̶  the world population reaching five billion on 11 July 1987.

Each year, World Population Day has a theme that highlights an issue relevant to the global population. For example, in 2011 – when the world population crossed the seven billion mark – the theme was on engaging with and activating all seven billion people in the challenges related to our planet. This year, the focus is on reproductive health and gender equality, and the United Nations has called for countries to attend to the 'unfinished business' of the 1994 International Conference on Population and Development. The 'unfinished business' is the recognition that achieving gender equality is essential if we are to achieve sustainable development.

Why is population growth and the associated issues such an important issue today? The magnitude of population growth has been colossal. It took the world hundreds of thousands of years (and modern humans about 10 000 years) to reach a global population of one billion. This milestone was reached in 1800. In the subsequent 220 years, the global population has grown to an estimated 7.8 billion. Linked to this growth has been massive changes in where people live. For most of human history, people largely lived in rural areas. 

In 2007, the global urban population outnumbered their rural counterparts for the first time. The shift was considerable – in 1950 approximately three-quarters of a million people lived in urban areas, but by 2018 this had swelled to 4,2 billion.  South Africa has followed this trend with more than two-thirds of South Africans now living in urban areas.

We are currently in the midst of a global COVID-19 pandemic, and in South Africa we are in month four of a state of strict lockdown. Hundreds of thousands of people have lost their jobs, children have been out of school for months and entire industries lie dormant. In this context, one might legitimately ask how important is World Population Day, and of what relevance is it for our current situation? 

The first reason lies squarely in the climate concerns the world now faces, which in turn have their roots in population growth and increased human encroachment on animal habitats. As it is now accepted (outside of a marginal group of climate change deniers), massive industrialisation in the last 200 years has resulted in significant environmental degradation.

The environmental catastrophe we may face (referred to as a Sixth Extinction by Elizabeth Kolbert (Kolbert, E. The Sixth Extinction: An Unnatural History. 2014. Henry Holt and Company) is a direct consequence of human activity resulting in massive increases in greenhouse gases which have led to temperature increase, shrinking glaciers and more frequent extreme weather events. The impacts of climate change are numerous, but a significant one has been the increasing displacement of people. As I have argued, a big part of this has been the shift from rural to urban centres, but increasingly it is linked to climate shifts and weather events. For example, in Bangladesh it has been estimated that by 2050 one in every seven people will have been displaced by climate changes.

'Climate migrants' are only one of the examples of how population movement is putting further pressure on already vulnerable cities, forcing an ever-increasing expansion into previously remote animal habitats and 'wild areas'.  Rapidly expanding cities are devastating wildlife to the point where we are losing our biodiversity at a rate of 1 000 times of what it was in pre-human times. The total mass of wild animals has been reduced by over 80%, while plant mass has been reduced by 50%.

One consequence of this is that the wildlife that remains, has had to adapt to living in a new proximity to human beings. These new 'intimate' configurations, and the increased contact between humans and wild animals, has massively increased outbreaks of infectious zoonotic diseases. Zoonotic diseases are caused by pathogens such as viruses, bacteria, and fungi that are transmitted to humans by animals (David Quammen. Spillover: Animal Infections and the Next Human Pandemic. 2012. W.W. Norton & Company). COVD-19 is only the most recent example of this, and whilst we are yet to track the specific animal where COVID-19 originated, that it originated in an animal is in little dispute. 

One of the conundrums of climate breakdown is that what is happening is not immediately visible and it requires a long-term view to appreciate what is happening – something that may be difficult for many. Act now to mitigate consequences in 20 years. Take a hit economically now so that your grandchildren will be in a better economic position than they might otherwise be.

A possible (beneficial) consequence of the current pandemic is that the reality of our encroachment, and the resultant diseases that we are going to be at risk of suffering from, is going to be increasingly difficult to deny or rationalise away. Added to this, we are also now beginning to see the shifts and changes at a much more personal level. For example, there is increasing evidence that as temperatures rise, pregnant women exposed to higher temperatures and pollution are more likely to have a child that is premature, underweight or even stillborn.

Finally, as the environment degrades, breadwinners (often men in poor countries) increasingly leave agricultural areas, out-migrating in order to seek work. This leads to an increase in the workload of women as well as reducing their access to resources. And in the aftermath of extreme weather events and disasters it is women who assume the burden of care for family members. This further limits their capacity to seek and engage in paid work.   

The current pandemic has shone a terrifying spotlight on human vulnerability and has highlighted our human arrogance and our delusional sense of superiority and dominance over the natural world. The world has been shut down by a minute virus (0,000065 mm in diameter), and we are at a loss about the way forward. Our current predicament offers an opportunity to 'build back better', and to acknowledge our interdependence with each other as well as the natural world. If we fail to heed the lesson, future pandemics and climate breakdown will make our current COVID-19 pandemic seem like a walk in the park. 

*Prof Mark Tomlinson is co-director of the Institute for Life Course Health Research in the Department of Global Health at Stellenbosch University.