Accuracy
The fact that we do not currently know the total number of species, in the past nor the present, makes it very difficult to accurately calculate the non-anthropogenically influenced extinction rates. As a rate, it is essential to know not just the number of extinctions, but also the number of non-extinctions. This fact, coupled with the fact that the rates do not remain constant, significantly reduces accuracy in estimates of the normal rate of extinctions.
Read more about this topic: Background Extinction Rate
Famous quotes containing the word accuracy:
“Such is the never-failing beauty and accuracy of language, the most perfect art in the world; the chisel of a thousand years retouches it.”
—Henry David Thoreau (1817–1862)
“In everything from athletic ability to popularity to looks, brains, and clothes, children rank themselves against others. At this age [7 and 8], children can tell you with amazing accuracy who has the coolest clothes, who tells the biggest lies, who is the best reader, who runs the fastest, and who is the most popular boy in the third grade.”
—Stanley I. Greenspan (20th century)
“As for farming, I am convinced that my genius dates from an older era than the agricultural. I would at least strike my spade into the earth with such careless freedom but accuracy as the woodpecker his bill into a tree.”
—Henry David Thoreau (1817–1862)