第六次“生物大灭绝”真的来临?

Earth’s sixth mass extinction is already underway – and humans are the driving force behind it, according to a new study.

地球的第六次物种大灭绝正在上演。一项新的研究发现，人类是其背后的推动力。

“Recent extinction rates are unprecedented in human history and highly unusual in Earth’s history,” according to a study published on June 19 in the journal Science Advances. “Our global society has started to destroy species of other organisms at an accelerating rate, initiating a mass extinction episodeunparalleled for 65 million years.”

6月19日Science Advances杂志上发表的一项研究表明，“最近的物种灭绝速度是人类历史上前所未有的，在地球发展史上也极其不寻常。我们人类社会已经开始在加速毁灭其他生物物种，并由此开启了一个6500万年以来最大规模的物种灭绝。”

Researchers used “extremely conservative assumptions” to determine extinction rates that prevailed in the past five periods of mass extinction. Still, they found the average rate of vertebrate species loss over the past century was up to 114 times higher than normal.

研究人员使用“非常保守的假设”来确定过去五大物种灭绝时期的物种灭绝速度,但他们仍然发现，在过去的一个世纪，脊椎动物物种的平均灭绝速度高出正常值的114倍。

For example, about 477 vertebrate species have gone extinct since 1900, according to the study.

例如，研究表明，自1900年以来大约有477种脊椎动物物种灭绝。

Based on previous extinctions, only nine species would have been expected to die off in the same time frame had it not been for mankind’s involvement.

根据以往的物种灭绝情况，如果没有人类的参与，在同样的时间内只会有九种物种灭绝。

Declining biodiversity

生物多样性的减少

“The number of species that have gone extinct in the last century would have taken... between 800 and 10,000 years to disappear,” the study reported.

研究表明：“上个世纪灭绝的物种数量本应该用800年到10,000年的时间才会消失的。”

“These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already underway.”

“这些估算说明，在过去几个世纪里生物多样性异常快速地在减少，这表明了第六次的大规模灭绝正在上演。”

The previous five mass extinctions happened well before mankind existed and are believed to have been mainly caused by natural disasters, such as asteroid impacts and volcanic eruptions.

之前的五次大规模物种灭绝发生在人类出现之前，而且这些灭绝被认为主要是由自然灾害引起的，如小行星撞击和火山喷发。

The last mass extinction happened some 65 million years ago, killing off the dinosaurs. Overall, each mass extinction event has rid the planet of up to 96 percent of its species each time.

上一次大规模的物种灭绝是发生在大约6,500万年前的恐龙灭绝。总的来说，每次大规模的灭绝事件都使地球减少96%的物种。

In the past few decades, several animal species have been labeled extinct, including the Chinesepaddlefish, Yangtze River dolphin, Pyrenean ibex and western black rhinoceros.

在过去的几十年里，一些动物都被打上了物种灭绝的标签，包括中华鲟、白鳍豚、比利牛斯山羊和西方黑犀牛。

In as little as three generations, the current pace of extinction could dramatically and permanently alter the number of species on the planet, the study said. In previous extinction events it took hundreds of thousands to millions of years for the planet to re-diversify.

这项研究表明，在今后短短三代人的时间内，以目前的灭绝速度足够可以显著和永久地改变地球上物种的数量。在以前的大规模灭绝之后，地球要花上几十万到几百万年的时间才能重新实现物种多样化。

Researchers said it’s not too late to avoid a true sixth mass extinction, but it will “require rapid, greatly intensified efforts to conserve already threatened species and to alleviate pressures on their populations – notably habitat loss, overexploitation for economic gain and climate change.”

研究人员表示，要想避免真正的第六次物种大灭绝为时还不算晚，但这“需要迅速地加大保护濒危物种的力度，以及降低这些物种所面临的各个方面的压力——特别是栖息地的丧失、为了经济利益的过度开发和气候变化。”

“However, the window of opportunity is rapidly closing.”

“然而，避免第六次物种灭绝的机会窗口正在迅速关闭。”