There have been five major extinction events during earth’s existence in which a large percentage of the species that were living at the time went extinct.

The first great extinction event was the End-Ordovician extinction, which happened 443.8 million years ago and was a marine life extinction event given that life on land had not yet evolved. Global cooling was the main cause of this extinction event and “25 percent of marine families and 85 percent of marine species” were lost during this time. https://www.britannica.com/science/mass-extinction-event

The second great extinction event was the Late Devonian extinction that happened 407.6 to 358.9 million years ago. This event is thought to be caused by changes in sea level, global cooling, and volcanic activity in oceans; and like the first extinction event, it primarily affected marine life. The die off was related to ocean anoxia – a state of insufficient oxygen. The losses during the second extinction “included 15–20 percent of marine families and 70–80 percent of all animal species.” https://www.britannica.com/science/mass-extinction-event

The third great extinction was the End-Permian extinction that occurred 265.1 to 251.9 million years ago. Global warming caused by massive volcanic activity is thought to be the main reason for the third extinction event, though some scientists contend that it was caused by comets or asteroids hitting the earth. The End Permian extinction was “the most dramatic die-off, eliminating about half of all families and about 90 percent of all species, which included some 95 percent of marine species (nearly wiping out brachiopods and corals) and about 70 percent of land species (including plants, insects, and vertebrates).” https://www.britannica.com/science/mass-extinction-event

The fourth major extinction event was the Late Triassic extinction that took place 201.3 million years ago. This extinction was caused by rapid climate change that was the result of volcanic activity or an asteroid impact. The Late Triassic extinction led to “20 percent of marine families and some 76 percent of all extant species to die out.” https://www.britannica.com/science/mass-extinction-event

The fifth major extinction event was the End-Cretaceous extinction, which happened 66 million years ago. This extinction may be the most well known among the general public as it is the extinction that took out the dinosaurs and was caused by large comets or asteroids striking the earth.

It may be difficult to find a silver lining when it comes to major extinction events, but had it not been for the Late Triassic extinction, the dinosaurs would likely not have flourished as they did, and if it had not been for the End Cretaceous extinction, mammals would likely not have evolved to flourish as they have, and we as humans would likely not be here today. So perhaps we should thank our lucky stars, or in this case our lucky comet or asteroid, that the impact of a celestial object 66 million years ago made our existence today a reality.

The good news in the midst of the five major extinction events that the earth has experienced is that “life finds a way.” That may be little consolation for the species that are now gone forever, but even after the most extreme extinction events, life has found a way to recover and flourish again. But it is important to note that it has taken life about ten million years to recover after each major extinction event. That may not be a long time geologically speaking, but for you and me, it might as well be an eternity.

At this point, you may be asking yourselves why I have just taken us on a ride down extinction memory lane and why any of this matters for us today. Sadly, the answer to this query is that it matters because the evidence is overwhelming that we are now experiencing the sixth great extinction event in Earth’s existence. The current extinction rate is 1,000 to 10,000 times greater than the normal background extinction rate. In the last 50 years, we have seen a massive loss of wildlife, with a 69% drop since 1970 according to the World Wildlife Fund Living Planet Report in 2022.

Amphibians may be the canary in the coal mine of the sixth great extinction, with half of all amphibians in decline and over 40% threatened with extinction according to the Amphibian Survival Alliance. Coral reefs are dying in warming oceans, with “half of the [world’s] coral reefs at risk by 2035” according to the World Economic Forum. Fisheries around the world have been decimated by overfishing, and marine life in general is threatened by ocean acidification.

We know how we got here, and we know what the problem is. It’s us, we are the problem. Our consumption and the unsustainable systems we have created have caused massive habitat loss with “97% of earth’s land altered by human activity” according. to Frontiers in Forests and Global Change, 2021. We have caused global deforestation, cutting down 10 million hectares of forests each year according to the United Nations Food and Agriculture Organization (UN FAO), 2020.

We have been involved in overhunting and overfishing around the world, disrupting the integrity, stability, and sustainability of ecosystems. We have caused global climate change, threatening life both on land and in the ocean.

In the midst of a global climate crisis and global biodiversity crisis that are mutually reinforcing one another, we are addicted to fossil fuels for energy and we are addicted to a system of animal agriculture that uses four times the amount of land for agriculture than we would be using if we all switched to a plant-based diet.

If we continue on our current path, we may see a loss of 50% of all species on earth by 2100. This will surely lead to both ecological collapse and economic collapse as the climate becomes unlivable for us and the ecosystems become unsustainable.

Life will find a way to survive even if we continue to hurl earth down the path of the sixth great extinction; but remember, it will take 10 million years for life to recover. Perhaps some highly evolved species will thank us for the ecological niches we opened up for them to evolve and flourish in ways that would not have been possible had we survived as a species, but that will be little consolation for us and little consolation for the many species of life we are taking out with us.

So the bad news, and it really is bad news, is that we are the problem. No other major extinction event has been caused by one species. If highly intelligent life forms evolve in the future, they may look at the layer of sediment in the geological record of our time and wonder “WTF happened then?”

The good news is that we know that we are the problem, and for the most part we know what we have to do to avoid our own demise and the demise of so much of the rest of life. We know that we can restore and regenerate large areas of habitat for wildlife and mitigate against the worst of climate change if we move away from industrial animal agriculture and move towards a plant-based diet. We know that by quickly weening ourselves off of fossil fuels that we can preserve a livable climate that will help save so many species of life, including ourselves.

The bad news is that we are the problem. The good news is that we know we are the problem and that there are many actions that we can take to address the mutually reinforcing crises of climate change and biodiversity loss. We know what the bad news is – we are the problem, and we know what the good news is – we are the solution. The yet to be determined news depends on whether we can develop the moral, spiritual, and political will to do what we know we have to do to avoid the continued progression of the sixth great extinction.