Predictions about the level of species extinctions
on Earth have all overestimated the process.
There are many reasons why scientists are failing
with these predictions. For example, we don't
know how many species there are in the world,
we don't have a sound method for estimating
extinction rates, and we don't understand
how species respond to human and natural disturbances.
Subjectivity dominates the dialogue when facts
are hard to come by.