background extinction rate

biology

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July 16, 2026

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The background extinction rate refers to the natural, ongoing loss of species due to environmental and ecological forces. This rate is estimated to be around one to five species per year when considering the entire fossil record. This is a slow, continuous process, unlike mass extinction events, which involve the rapid loss of a significant portion of Earth's species across a wide area.12

Human activities, however, have dramatically accelerated extinction rates, potentially 1,000 times the background rate. This is primarily due to deforestation, habitat loss, hunting, pollution, and climate change. Scientists estimate that current extinction rates are significantly higher than the natural background rate, and future rates are predicted to be even higher.324

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conservation
Calculating background extinction rates
To discern the effect of modern human activity on the loss of species requires determining how fast species disappeared in the absence of that activity. Studies of marine fossils show that species last about 1–10 million years. Assume that all these extinctions…
Read More
To discern the effect of modern human activity on the loss of species requires determining how fast species disappeared in the absence of that activity. Studies of marine fossils show that species last about 1–10 million years. Assume that all these extinctions…
Read More