May 22 is the International Day for Biodiversity. In 2018, it comes as the recognition that we are living through the Sixth Mass Extinction is growing widely. As we celebrate biodiversity, it is under greater threat than ever before. Is all lost, or can we turn things around?
Human impact on biodiversity
A recently published study has revealed that humans constitute less than a ten-thousandth of the weight of all living things on Earth. Bacteria account for 13%, plants 82% and all animal life just 5%, with humans a fraction of that. Despite the insiginificance of our physical presence, it also calculates that humanity is responsible for eradicating 83% of wild mammals, and half of all plants.
Climate change remains one of the gravest threats to biodiversity. This month, another study was published, predicting that half of insect habitats could be lost unless further carbon emissions cuts are pledged by nations.
Last year, a group of scientists, including Population Matters patron Paul Ehrlich, described the level of species extinction that is currently taking place as “biological annihilation“.
Hope for biodiversity?
In April, a scientific paper was published, offering some hope. From bottleneck to breakthrough argues that the pressures that have driven our decline in biodiversity will soon ease, and a smaller, wealthier, more urbanised population will put less pressure on wild habitats, be free to consume more responsibly and be in a position to foster the recovery of species and biodiversity.
The paper’s optimism derives from a bold prediction that “100 years from now, the Earth could be inhabited by between 6 and 8 billion people”. That conjecture is based on a deep allegiance to the theory of demographic transition, which assumes increasing prosperity leads to lowered fertility (ie family size), operating in a virtuous cycle bringing birth rates down and reducing population. The authors identify urbanisation as another factor contributing to increased decline in fertility rates.
Demographic transition is not happening everywhere, however, and without effective family planning and education will simply not take place. Indeed, the authors’ population figures are significantly lower than the lowest UN’s projected “95% certainty” range for the end of this century. They are possible to achieve, but not without concerted effort. The authors do not call for such effort, relying instead on the belief that such changes are inevitable.
No hope without action
The paper offers a vision of a future in which population pressure is so reduced as to offer hope for recovery in our living systems .However, threats to biodiversity are extreme and time is running out. As the authors themselves put it, “the profound danger is that by the time the foundations of recovery are in place, little of wildlife and wild places will be left.” Their theory is speculative, and very unlikely to come about under present policies. But action can be taken.