The New Global Biodiversity Framework and the Sixth Mass Extinction: What is at Stake

The successful negotiation of the Kunming-Montréal Global Biodiversity Framework (GBF) at the United Nations Biodiversity Conference (known as COP15), chaired by China and hosted by Canada, is a milestone in the multilateral effort to halt the assault mainly by humans on the world’s plant and animal life. It aims to conserve at least 30 percent of global lands, fresh water and ocean by 2030, with parties adopting ambitious targets for ecosystem restoration, sustainable use of biodiversity, reduction in harmful pollutants and inclusion of indigenous peoples and local communities in conservation efforts. It will also seek to reduce US$500 billion in annual harmful government subsidies and cut food waste in half.

“We have a pact with nature that will deliver ambition and financing, a pact that will deliver innovative resource streams to the poorer countries in the developing world and, most important, will also work to ensure benefit sharing from the genetic resources in developed countries and ensure that those benefits can go to the people where these resources are,” Inger Andersen, executive director of the UN Environment Programme, explained at the conclusion of the conference. This accord came on the heels of the COP27 United Nations Climate Change Conference in Egypt, where participants set a landmark agreement on a new “loss and damage” fund for vulnerable countries hit hardest by global warming. It also followed a major agreement at the Parties to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) conference in Panama where over 160 governments adopted proposals to regulate international trade in more than 500 new species, a record number. 

“Now the real work begins,” Andersen declared after the passing of the GBF. “While we have a framework, resources and pathways, we now have to roll up our sleeves and get the work done.”

What is at stake in the global battle for biodiversity?

Species are going extinct at an unusually high rate. Our efforts now will prevent a future too ghastly to contemplate. Mounting evidence is pointing to the world having entered a sixth mass extinction. If the current rate of extinction continues, we could lose most species by 2200. The implication for human health and wellbeing is dire but not inevitable.

In the timeline of fossil evidence going right back to the first inkling of any life on Earth – over 3.5 billion years ago – almost 99 percent of all species that have ever existed are now extinct. That means that as species evolve over time – a process known as “speciation” – they replace other species that go extinct. Extinctions and speciations do not happen at uniform rates through time. Instead, they tend to occur in large pulses interspersed by long periods of relative stability. These extinction pulses are what scientists refer to as mass extinction events. 

The Cambrian explosion was a burst of speciation some 540 million years ago. Since then, at least five mass extinction events have been identified in the fossil record (and probably scores of smaller ones). Arguably the most infamous of these was when a giant asteroid smashed into Earth about 66 million years ago in what is now the Gulf of Mexico. The collision vaporized species immediately within the blast zone. Later, species were killed off by climate change arising from pulverized particulates suspended in the atmosphere, as well as intense volcano activity stimulated by the buckling of the Earth’s crust from the asteroid’s impact. Together, about 76 percent of all species around at the time went extinct, of which the disappearance of the dinosaurs is most well-known. But dinosaurs did not disappear altogether; the survivors just evolved into birds.

To be classified as a mass extinction, at least 75 percent of all the species on Earth must go extinct within a “short” geological period of less than 2.8 million years. That timeframe seems long to us because modern humans have only existed for about 200,000 years so far. As a species, humans have been implicated in smaller extinction events going back to the late Pleistocene (around 50,000 years ago) to the early Holocene (around 12,000 years ago) when most of the “megafauna” such as woolly mammoths, giant sloths, diprotodons and cave bears disappeared from nearly every continent over a few thousand years. 

But it is not the total number of extinctions we should focus on; rather, it is the extinction rate. If past mass extinctions took nearly three million years to ensue, then we should instead examine how many species go extinct per unit of time relative to the “background” extinction rate that occurs between mass-extinction events.

According to the fossil record, the average “lifespan” of a species is around one million years, which equates to a background rate of about 0.1–2.0 extinctions per million “species-years”. This makes the number of observed extinctions in the modern era 10 to 10,000 times higher than the background rate. Even the most conservative estimates that ignore undetected extinctions firmly place the modern era well within the expected range to qualify as a mass extinction.

An optimist might contend that surely the rate of loss will decline with time such that we would be unlikely to meet the 75 percent threshold. The outlook, however, is not at all rosy. The devastation wrought to date means the extinction rate is only likely to accelerate.

Most of the damage to the Earth’s life-support system has happened over the last century. The global human population has tripled since 1950, and there are now approximately one million species threatened with imminent extinction due to massive population declines, representing about 10–15 percent of all complex life on Earth. Since the start of agriculture around 11,000 years ago, the total amount of vegetation on Earth has halved. Less than 15 percent of all wetlands recorded 300 years ago are still present today, and more than two-thirds of the world’s oceans are compromised to some extent by human activity. 

This is not to mention climate change. Recent evidence suggests global warming causes up to ten times more extinctions than we might expect by looking only at an upper temperature limit for species. In fact, when we take the relationships between species into account – such as predators depending on their prey, parasites depending on their hosts, or flowering plants depending on their pollinators – near-future extinctions are expected to skyrocket. 

The grim outlook, however, does not justify inaction. On the contrary, we could potentially limit the damage if societies around the globe embraced certain fundamental, yet achievable, changes. We could abolish the goal of perpetual economic growth and force companies to restore the environment using established mechanisms such as carbon pricing. We could limit undue corporate influence on political decision-making, and end corporate lobbying of politicians. Educating and empowering women, including providing greater self-determination in family planning, would help stem environmental destruction.

With real effort and longer-term planning, as set out in the GBF, we could make our future just that little bit less ghastly.