Biology / Unit 14 Bio 3709 short lesson, about 20 seconds
How the IUCN Red List Classifies Extinction Risk
Captions available
The idea
The IUCN Red List orders extinction risk from least concern through critically endangered and extinct, intermediate categories included, using size, trend, and range.
In practice
A species with a small, declining population and shrinking range classifies well up the ordering.
Where people slip
Assuming every criterion must be met is the error — meeting one threshold alone suffices.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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