[ According to a paper published in Science the current rates of extinction are 1000 times the background rate. This estimate is higher than previous estimates is due to a more sophisticated analysis. ]
Pimm, S.L., et al, 30 May 2014. The biodiversity of species and their rates of extinction, distribution, and protection. Science.
Current rates of extinction are about 1000 times the background rate of extinction. These are higher than previously estimated and likely still underestimated. Future rates will depend on many factors and are poised to increase.
Recent studies clarify where the most vulnerable species live, where and how humanity changes the planet, and how this drives extinctions. We assess key statistics about species, their distribution, and their status. Those we know best have large geographical ranges and are often common within them. Most known species have small ranges. The numbers of small-ranged species are increasing quickly, even in well-known taxa. They are geographically concentrated and are disproportionately likely to be threatened or already extinct. Although there has been rapid progress in developing protected areas, such efforts are not ecologically representative, nor do they optimally protect biodiversity.
Concerns about biodiversity arise because present extinction rates are exceptionally high. Consequently, we first compare current extinction rates to those before human actions elevated them.
Other articles about biodiversity:
George Monbiot. September 15, 2016. Disposable Planet. The Guardian.
Chris Mooney. September 14, 2016. What the ‘sixth extinction’ will look like in the oceans: The largest species die off first. Washington Post.