Biology / Unit 14 Bio 3713 short lesson, about 20 seconds
How an Extinction-Risk Assessment Is Constructed
Captions available
The idea
A risk assessment combines field-survey population estimates, per Bio 3545, trend data, and range mapping, evaluated against fixed numeric thresholds.
In practice
Comparing a species' current range against its historic extent quantifies the decline one criterion requires.
Where people slip
Assuming one data source suffices is the error — population, trend, and range combine into one assessment.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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