Scientific American又來了！第六次大滅絕，地球人是罪魁禍首。

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第六次大滅絕是托福生物學科經常出現的考題，跟先前五次物種大滅絕不同的是，這回(第六次)的滅絕，科學家認為是人為因素導致的。目前全球各地的專家學者都在研究物種消失對於地球的影響。最新研究指出，第六次大滅絕還在起步階段，目前尚未(記得英文的for now/yet的意涵)影響地球的生物多樣性 biodiversity。不過這並不代表問題不嚴重，因為類似的滅絕行動是不可逆的 irreversible，一旦滅絕啟動，許多傷害便難以彌補，冥頑不靈的人類又不知覺醒，地球的未來還是令人感到憂慮。

Biodiversity Survives Extinctions for Now

A meta-analysis of ecosystems finds that species losses in any given place do not yet translate to large changes in the number of different species in that place. David Biello reports

We are living during what seem to be the opening stages of the sixth mass extinction第六次大滅絕 in our planet's 4.5 billion year history. Species of birds, fish, mammals and plants are disappearing at speeds rarely experienced, thanks in large part to 因為human activities: pollution, climate change, habitat destruction and other damage. But extinction apparently does not mean less biodiversity—at least not yet.

A new look at ecosystems from the poles南北極 to the tropics熱帶地區 shows that losses in the number of species in any given place do not yet translate to large changes in the overall number of different species there. The study is in the journal Science. 

The researchers analyzed 100 surveys that followed more than 35,000 different species over various lengths of time. These long-term studies found that the number of different species in, say, a coral reef珊瑚礁 remains relatively constant. Because the loss of a species, either locally在地的/當地的 or entirely, is often balanced by被…平衡 the arrival of a new species.

The meta-analysis在…之後showed that 40 percent of places had more species present, 40 percent had less and 20 percent were unchanged. In other words, the ecosystems of the current Anthropocene era人類紀 are transformed, but just as diverse—so far anyway. We are living in a world of novel全新的 ecosystems.

—David Biello