I tend to think we have a major biodiversity crisis, but it would take either a fast acceleration of current extinction rates or a couple of centuries at current extinction rates, for the current process to become a sixth mass extinction.” 
 
 The team behind the new analysis said “rapid, greatly intensified efforts” would be needed to stop or slow the extinctions currently underway. Even under our assumptions, which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 100 times higher than the background rate. Study reveals rate of extinction for species in the 20th century has been up to 100 times higher than would have been normal without human impact 
 
 The modern world is experiencing a “sixth great extinction” of animal species even when the lowest estimates of extinction rates are considered, scientists have warned. Related: Pope Francis Urges Revolution to Save Earth 
 
 A tally by the International Union for Conservation of Nature shows trends in the extinction of various groups of animal species. For example, amphibians, comprising of ~7300 species, show an accelerating rate of extinction: only 34 extinctions have been documented with a high level of certainty since 1500, yet >100 species have likely disappeared since 1980 (17, 23). "Avoiding a true sixth mass extinction will require rapid, greatly intensified efforts to conserve already threatened species, and to alleviate pressures on their populations - notably habitat loss, over-exploitation for economic gain and climate change," the study's authors write.
– Feeling upbeat? Enough of that: Planet Earth is undergoing a sixth mass extinction that will likely annihilate the human race unless we can curb the trend, scientists say. According to a new paper, the current rate of species extinction outpaces the natural rate far more than anyone knew, NBC News reports. The analysis "employed better knowledge" of Earth's natural extinction rate, the Guardian reports, upping the number from one extinction per million species annually to two extinctions. It then compared that to a current extinction rate that study authors consider conservative. Presto, they got a rate since 1900 that's eight to 100 times worse than the natural one. "We were very surprised to see how bad it is," says study leader Gerardo Ceballos. "This is very depressing." "If it is allowed to continue, life would take millions of years to recover, and our species itself would disappear early on," says Ceballos. But nations can reverse the crisis—which has been linked to deforestation, industrialization, and other human factors—by conserving threatened species and lowering pressures on their populations, the paper says. So far critics seem to buy the paper's basic math but doubt that species extinction will continue at this high rate for centuries. "It is likely the problem will decline rapidly because most countries will be rich and care much for the natural world," writes one environmentalist. Earth has seen five other mass extinctions, including one 443 million years ago that killed off 83% of sea life, and the most recent, which wiped out the dinosaurs 66 million years ago, the Telegraph notes.