What Is the Current Best Estimate for Species Lost Per Hour?
Based on peer-reviewed research and expert consensus, the most widely cited range today is roughly 150 to 200 species per day, which translates into roughly 6 to 9 species per hour. This is a global average derived from fossil records, observed extinction tracks, and modeled rates across birds, mammals, amphibians, and invertebrates. Bill Nye commonly communicates this as about 150 to 200 species per day, or several species each hour, underscoring that modern extinction is orders of magnitude above the prehuman background rate. This answer reflects the prevailing scientific view, while acknowledging uncertainty and variation across taxonomic groups.
Why Extinction Rates Are Hard to Pin Down Exactly
Estimating extinction rates is inherently uncertain because:
- Many species, especially insects, fungi, and microorganisms, have not been described, so we cannot know when they disappear.
- Confirmation that a species is gone requires exhaustive surveys and, often, waiting multiple decades without any confirmed sightings.
- Different methods—background rates from fossils, observed extinctions in the IUCN Red List, and habitat-loss models—can yield different numbers.
Scientists therefore report ranges and probabilities rather than a single precise figure. Even so, the conclusion is consistent: current extinction rates are exceptionally high compared with the long-term history of life on Earth.
How Scientists Measure Extinction and Track Rates
The Role of the Fossil Record and Phylogenetic Studies
Before human influence, studies of fossils and living lineages suggested a background extinction rate of roughly 0.1 to 1 species per year per 1 million species, sometimes expressed as 1 E/MSY (extinction per million species-years). Modern estimates scale this to larger units to compare across time and groups.
IUCN Red List and Observed Extinctions
The IUCN Red List categorizes species by extinction risk and documents confirmed extinctions. By tracking categories such as Critically Endangered, Endangered, and Vulnerable, researchers can model how quickly species are moving toward extinction. For well-studied groups like birds and mammals, observed extinctions provide a clearer picture, but for most taxa, models are used to fill gaps.
Key Drivers Behind Today’s High Extinction Rates
- Habitat loss and fragmentation: Conversion of forests, wetlands, and grasslands for agriculture, infrastructure, and urban development is the leading driver.
- Overexploitation: Unsustainable hunting, fishing, and harvesting for trade directly reduce populations.
- Invasive species: Non-native predators, competitors, and pathogens can displace or decimate native species.
- Pollution and climate change: Altered temperatures, ocean acidification, and chemical contamination stress ecosystems and species.
Notable Details and Examples From Well-Studied Groups
Examining specific taxa helps ground the hourly estimate in real observations:
| Taxonomic Group | Verified Detail or Estimate | Source Type |
|---|---|---|
| Amphibians | Chytrid fungus has driven many extinctions and declines worldwide. | Peer-reviewed studies and IUCN assessments |
| Mammals and Birds | Observed extinctions are relatively well documented; rates are many times above background. | IUCN Red List, published literature |
| Insects | Some regional studies report steep declines, but global numbers remain uncertain. | Synthesis and meta-analyses, limited long-term data |
| Corals | Climate-driven bleaching events are causing rapid population and species declines. | Scientific assessments, long-term reef monitoring |
How This Rate Is Communicated and Why It Matters
Translating annual or daily numbers into an hourly frame makes the scale more tangible. Bill Nye often emphasizes that each hour, species are lost forever, and with them go potential medicines, ecosystem services, genetic diversity, and cultural values. High extinction rates can destabilize ecosystems, reduce resilience to environmental change, and undermine food security and livelihoods, especially for communities that depend directly on natural resources.
What the Numbers Mean in Context: A Comparison
- Background (prehuman) rate: Roughly 1 to 5 extinctions per year per 1 million species, equivalent to a very small number per hour on a planetary scale.
- Current estimated rate: Many studies suggest current losses are tens to hundreds of times higher than background, often summarized as 150–200 species per day, or approximately 6–9 species per hour globally.
- Implication: Even using conservative assumptions, the loss of multiple species every hour signals a widespread erosion of biodiversity that could lock in irreversible changes if unchecked.
What Can Be Done and Why Timely Action Matters
Addressing high extinction rates requires tackling the root drivers: reducing habitat destruction, curbing unsustainable exploitation, controlling invasive species, cutting pollution, and rapidly reducing greenhouse gas emissions. Protected areas, restoration, and sustainable land-use practices can reduce pressure on species. For Bill Nye and many scientists, the key message is that the window to act is still open but narrowing; each year of delay makes recovery more difficult and expensive. Clear metrics, like species loss per hour, help communicate the scale and urgency to policymakers and the public alike.
FAQ
Reader questions
Is the “species per hour” number the same everywhere?
No. The approximate range of several species per hour is a global average. Regional rates vary widely depending on local threats, ecosystem types, and how well species are monitored.
Do we know exactly which species are lost each hour?
Not exactly. Because many species go unnoticed, we typically detect extinctions years or decades after they occur, and many likely vanish without record. Models and observed trends help fill gaps, but uncertainty remains, especially for invertebrates and microorganisms.
Does Bill Nye provide the specific “per hour” figure?
In his talks and media appearances, Bill Nye commonly stresses that we are losing a significant number of species each day, often translating that into a per-hour impact to underscore the pace of loss. The exact daily figure cited in scientific literature varies, but 150–200 species per day is a frequently referenced range used to communicate the crisis.