Practice question · Numerical answer
The background extinction rate is about 1 species per million species per year. If current rates are 500 times higher, how many extinctions per million species per year does that represent?
Hints
- Multiply the background rate by the stated factor.
- Compute 1 x 500.
Show the answer
500
Why
500 per million per year. Even the low end of current estimates puts the rate two orders of magnitude above background, which is the quantitative basis for calling this a mass extinction.
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