Scientists warn today’s biodiversity crisis mirrors past mass die-offs that once reshaped life on Earth.
Earth has experienced five devastating mass extinctions that wiped out most life on the planet, but the sixth one isn’t coming from outer space or volcanic eruptions – it’s being caused by humans. Wildlife populations have plummeted by 73% since 1970, and we’re losing species at rates 1,000 to 10,000 times faster than natural background extinction rates.
Nearly one million species are currently at risk of extinction in what scientists are calling the most severe biodiversity crisis in human history.
1. We’re losing species 10,000 times faster than the natural rate
Current extinction rates are estimated to be between 1,000 and 10,000 times higher than natural extinction rates, meaning we’re experiencing unprecedented biodiversity loss in Earth’s history. During normal periods, species naturally go extinct at a rate of about 1-5 species per year globally. Today, we’re losing dozens or potentially hundreds of species every single day.
This acceleration puts the current crisis on par with the asteroid impact that killed the dinosaurs, except it’s happening over decades instead of years. The speed of loss is so fast that ecosystems can’t adapt or recover between extinctions. Unlike previous mass extinctions caused by natural disasters, this one is entirely preventable – and entirely our fault.
2. Nearly one million species are currently facing extinction
According to UN assessments, nearly one million species are currently at risk of extinction, representing about 25% of all systematically assessed plant and animal groups. This isn’t a future prediction – it’s the current reality of how many species are hanging by a thread right now. More than 40% of amphibian species, almost 33% of reef-forming corals, and more than a third of all marine mammals are threatened.
The scale of this crisis is staggering when you realize that each of these species represents millions of years of evolutionary development that will be lost forever. Every extinction eliminates unique genetic information, ecological relationships, and potential benefits to humans that we may never even discover. We’re essentially burning down the library of life before we’ve read most of the books.
3. Wildlife populations have crashed by 73% in just 50 years
The 2024 Living Planet Index reports that wildlife populations have declined by an average of 73% since 1970 – a catastrophic collapse that’s happened within a single human lifetime. This means that for every 100 animals that existed when today’s grandparents were young, only 27 remain. The rate of decline is accelerating rather than slowing down.
This collapse affects everything from tiny insects to large mammals, with some regions experiencing even steeper declines. Freshwater species have been hit hardest, with some populations declining by over 80%. The speed of this collapse mirrors the rapid die-offs seen in previous mass extinctions, but this time it’s happening in real-time and we can watch it unfold.
4. Insect populations are collapsing faster than we can count them
Scientists estimate that about 10% of insect species are threatened with extinction, but this may be a conservative estimate since most insect species haven’t been studied or even discovered yet. Insect biomass is declining by 2.5% per year globally, which means insect populations are halving every generation. Some regions have lost over 75% of their flying insects in just 25 years.
This insect apocalypse threatens to collapse entire food webs since insects pollinate most plants and serve as food for countless birds, mammals, and other animals. Without insects, agricultural systems would fail, ecosystems would unravel, and human food security would be severely threatened. The loss of insects represents a foundational collapse that could trigger cascading extinctions throughout entire ecosystems.
5. Ocean acidification is dissolving marine life like the ancient extinctions
Rising carbon dioxide levels are making oceans more acidic, dissolving the shells and skeletons of marine creatures just like during the Permian extinction 252 million years ago. Coral reefs are experiencing unprecedented bleaching events that kill entire reef systems, while shellfish struggle to build and maintain their protective shells in increasingly acidic water.
Ocean acidification is happening 10 times faster today than during the worst extinction event in Earth’s history. Marine ecosystems that took millions of years to evolve are being chemically altered within decades. This represents a fundamental change to ocean chemistry that threatens the base of marine food webs and could trigger widespread ocean ecosystem collapse.
6. Climate change is creating the same killing conditions as past mass extinctions
Rapid climate change has been the common factor in most of Earth’s mass extinctions, and we’re currently experiencing climate change at a rate comparable to or faster than these ancient disasters. Global temperatures are rising at rates that most species cannot adapt to, while changing precipitation patterns are creating droughts and floods that devastate ecosystems.
A recent study found that close to one-third of species globally would be at risk of extinction by the end of the century if greenhouse gas emissions continue at current levels. The temperature changes we’re creating mirror the conditions that killed off most life during previous mass extinctions, but compressed into a much shorter timeframe.
7. Habitat destruction is eliminating entire ecosystems before we can study them
Human activities have significantly altered 75% of terrestrial environments and 66% of marine environments, destroying habitats faster than species can adapt or migrate to new areas. Primary forests, wetlands, and grasslands are being converted to agriculture and development at unprecedented rates. We’re essentially erasing entire ecosystems along with all the species they contain.
The Amazon rainforest alone contains an estimated 10% of known species, but deforestation is eliminating vast areas before scientists can even catalog what lives there. Every acre of habitat destroyed represents potential extinctions of species we’ve never discovered, studied, or understood. We’re conducting a massive experiment in ecosystem destruction with no way to undo the results.
8. Pollution is creating dead zones like ancient toxic extinction events
Chemical pollution, plastic waste, and agricultural runoff are creating ocean dead zones and contaminated landscapes that mirror the toxic conditions during Earth’s worst mass extinctions. Pesticides are killing off pollinators and other beneficial insects, while plastic pollution is found in organisms from the deepest ocean trenches to the highest mountains.
These pollution impacts compound with climate change and habitat loss to create multiple simultaneous stresses that overwhelm species’ ability to adapt. The combination of chemical contamination, physical waste, and altered ecosystems creates conditions that no species evolved to handle, leading to widespread population crashes and extinctions.
9. Co-extinctions are creating cascading species loss throughout ecosystems
When one species goes extinct, it often triggers the extinction of other species that depended on it, creating chain reactions of biodiversity loss called co-extinctions. These domino effects mean that losing a single keystone species can collapse entire ecological networks. Pollinators, seed dispersers, and predators play critical roles that, when eliminated, cause multiple other species to disappear.
The UN warns that these co-extinctions are accelerating as ecosystems lose their stability and resilience. Unlike single-species extinctions, these cascading losses can happen very rapidly once tipping points are reached. We’re seeing early signs of these ecosystem collapses in coral reefs, forests, and grasslands worldwide, suggesting that mass co-extinction events may already be underway.