Editing Extinction event (section)

{{Short description|Widespread and rapid decrease in the biodiversity on Earth}}
{{About|mass extinction|other uses|Extinction Event (disambiguation)}}
{{Annotated image/Extinction |caption=The blue graph shows the apparent ''percentage'' (not the absolute number) of marine [[animal]] [[genus|genera]] becoming extinct during any given time interval. It does not represent all marine species, just those that are readily fossilized. The labels of the traditional "Big Five" extinction events and the more recently recognised [[Capitanian mass extinction event]] are clickable links. The two extinction events occurring in the Cambrian (far left) are very large in percentage magnitude, but small in absolute numbers of known taxa due to the relative scarcity of fossil-producing life at that time. ''([[:Image:Extinction intensity.svg|source and image info]])''}}
{{use dmy dates|date=January 2022}}
An '''extinction event''' (also known as a '''mass extinction''' or '''biotic crisis''') is a widespread and rapid decrease in the [[biodiversity]] on [[Earth]]. Such an event is identified by a sharp fall in the diversity and abundance of [[multicellular organism]]s. It occurs when the rate of [[extinction]] increases with respect to the [[background extinction rate]]<ref name=Sudakow2022>{{cite journal |last1=Sudakow |first1=Ivan |last2=Myers |first2=Corinne |last3=Petrovskii |first3=Sergei |last4=Sumrall |first4=Colin D. |last5=Witts |first5=James |date=July 2022 |title=Knowledge gaps and missing links in understanding mass extinctions: Can mathematical modeling help? |journal=Physics of Life Reviews |volume=41 |pages=22–57 |doi=10.1016/j.plrev.2022.04.001 |pmid=35523056 |bibcode=2022PhLRv..41...22S |s2cid=248215038 |doi-access=free }}</ref> and the rate of [[speciation]]. 

Estimates of the number of major mass extinctions in the last 540&nbsp;million years range from as few as five to more than twenty. These differences stem from disagreement as to what constitutes a "major" extinction event, and the data chosen to measure past diversity.