The rate at which species were once thought to be speeding towards extinction is grossly overrated, a new study shows.
Extinction rates could be at least two times slower than previously thought. Co-author of the study, Stephen Hubbell, notes that the accelerated rates of species extinction can still be attributed to humans. However, initial studies on species extinction done by the Intergovernmental Panel on Climate Change and the 2005 UN Millennium Ecosystem Assessment are based on “fundamentally flawed methods” that may highly overstate the rate of extinction, new researchers report.
Hubbell points out, “This is welcome news in that we have bought a little time for saving species. But it is unwelcome news because we have to redo a whole lot of research that was done incorrectly.”
For nearly three decades, scientists have been measuring the rate of extinction using incorrect concepts. When forecasts proved extremely far off the mark, scientists added on a new theory of “extinction debt” to explain the discrepancy. Extinction debt is the idea that species already in decline are fated to become extinct even if it takes many, many years for the last individuals of the species to die out. However, new researchers refute the existence of extinction debt.
Although the perceived rate of extinction now appears to be slower than previously thought, human activity remains the dominant driver of species extinction. Only one-fifth of the earth’s forests are still considered wild, and agriculture now takes up nearly 40 percent of ice-free land.
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