演講簡介：人類無處不在，足跡遍布每個大陸，不管是叢林、海洋還是苔原那種最孤立的角落。 我們的影響如此深遠，大多數科學家認為人類在地球的地質記錄上留下了永久的印記。 那麼，如果人類突然全部消失了，地球又會變成什麼樣子呢？
演講題目：What would happen if every human suddenly disappeared?
視頻來源：騰訊
中英文字幕
Human beings are everywhere. With settlements on every continent, we can be found in the most isolated corners of Earth’s jungles, oceans,and tundras. Our impact is so profound, most scientists believe humanity has left a permanent mark on Earth’s geological record. So what would happen if suddenly, every human on Earth disappeared?
人類無所不在。在每塊大陸上都有人定居，人類的蹤跡甚至遍及地球上最與世隔絕的角落，包括叢林、海洋，和凍原。我們的影響非常深刻，大部分科學家相信人類在地球的地理紀錄上留下了永久性的痕跡。所以，如果地球上的每個人都突然消失了，會如何？
With no one maintaining them, some of our creations backfire immediately. Hours after we disappear, oil refineries malfunction, producing month-long blazes at plants like the ones in western India, the southern United States, and South Korea.
一些由人類創造出來的東西，在沒人維護的情況下會立刻出事。我們消失幾小時之後，煉油廠會故障，產生長達數月的火災，燒毀植物，就像發生在西印度、美國南部，及南韓的狀況一樣。
In underground rail systems like those in London, Moscow, and New York City, hundreds of drainage pumps are abandoned, flooding the tunnels in just three days. By the end of the first week, most emergency generators have shut down, and once the fires have gone out, the earth goes dark for the first time in centuries.
在地下的鐵路系統中，像是在倫敦、莫斯科，和紐約市的系統，數百個排水泵被棄之不顧，三天之內隧道就會被水淹掉。在第一周結束時，大部分緊急發電機都會停止運作，一旦大火熄滅，地球將會數世紀以來首次陷入一片黑暗。
After the first catastrophic month, changes come more gradually. Within 20 years, sidewalks have been torn apart by weeds and tree roots.Around this time, flooded tunnels erode the streets above into urban rivers. In temperate climates, the cycle of seasons freezes and thaws these waterways, cracking pavement and concrete foundations.
在災難性的第一個月之後，改變會漸漸發生。二十年內，人行道會因為雜草和樹根而四分五裂。大約在這時，淹水的隧道會侵蝕到上方的街道，將之變成城市河流。在溫帶氣候區，四季循環會讓這些水道結冰之後又融化，路面和混凝土地基會因而破裂。
Leaking pipes cause the same reaction in concrete buildings, and within 200 winters, most skyscrapers buckle and tumble down. In cities built in river deltas like Houston, these buildings eventually wash away completely -filling nearby tributaries with crushed concrete.
在混凝土建築物中，破漏的管線也會造成同樣的反應，在兩百個冬天之內，多數摩天大樓都會變形倒塌。在河流三角洲上的城市，像是休斯敦，這些建築物最終會被完全衝走——讓附近的支流滿是破碎的混擬土。
Rural and suburban areas decay more slowly, but in largely unsurprising ways. Leaks, mold, bug and rodent infestations - all the usual enemies of the homeowner- now go uncontested. Within 75 years, most houses' supporting beams have rotted and sagged, and the resulting collapsed heap is now home to local rodents and lizards.
鄉村和郊區的衰敗速度會比較慢，但衰敗方式大多不會讓人感到意外。漏水、發黴、蟲害，和囓齒目動物大量出沒——屋主最常見的所有敵人——現在都無法無天了。在七十五年內，大部分房子的支柱會腐壞和下陷，造成許多房子倒塌，成為當地囓齒目動物和蜥蜴的家。
But in this post-human world, 「local」 has a new meaning. Our cities are full of imported plants, which now run wild across their adopted homes.Water hyacinth coat the waterways of Shanghai in a thick green carpet.Poisonous giant hogweeds overgrow the banks of London’s Thames River.
但在這個「後人類」世界，「當地」這個詞有新的意義。我們的城市滿是外來的植物，這些植物如今在收養它們的家庭中放肆生長。上海水道表面滿是布袋蓮，形成厚厚的綠色地毯。有毒的巨型豬草在倫敦泰晤士河河岸過度生長。
Chinese Ailanthus trees burst through New York City streets. And as sunken skyscrapers add crumbled concrete to the new forest floor,the soil acidity plummets, potentially allowing new plant life to thrive. This post-human biodiversity extends into the animal kingdom, as well.
臭椿長滿了紐約市街道。下陷的摩天大樓，在新的森林地面上增加了破碎的混擬土，土壤pH值降低（也就是鹼性的程度減少），可能會讓新的植物生命茂盛生長。「後人類」的生物多樣性也延伸到了動物王國裡。
Animals follow the unchecked spread of native and non-native plants,venturing into new habitats with the help of our leftover bridges. In general, our infrastructure saves some animals and dooms others.
動物會追循著本土與非本土植物不受管制的散播，靠著剩下的橋梁協助，冒險進入新居住地。一般來說，我們的基礎建設拯救了一些動物，也害死了一些動物。
Cockroaches continue to thrive in their native tropical habitats, but without our heating systems, their urban cousins likely freeze and die out in just two winters. And most domesticated animals are unable to survive without us – save for a handful of resourceful pigs, dogs, and feral housecats.
蟑螂在牠們原生的熱帶居住地依然很繁盛，但沒有我們的暖氣系統，牠們的都市堂兄弟姐妹很可能會在兩個冬天之後就冷死而絕跡。最習慣家庭生活的動物，沒有我們就會無法生存——除了一些很機智的豬、狗，和變野的家貓。
Conversely, the reduced light pollution saves over a billion birds each year whose migrations were disrupted by blinking communication tower lights and high-tension wires. And mosquitos multiply endlessly in one of their favorite manmade nurseries – rubber tires, which last for almost a thousand years.
反過來說，光害的減少每年可以拯救超過十億隻鳥，過去牠們的遷移會被用閃光溝通的燈塔及高拉力鋼線給打斷。蚊子在牠們最喜歡的人造滋生地之一不斷繁殖——橡膠輪胎，它們能使用近一千年。
As fauna and flora flourish, Earth’s climate slowly recovers from millennia of human impact. Within 35,000 years, the plant cycle removes the last traces of lead left by the Industrial Revolution from Earth’s soil, and it may take up to 65,000 years beyond that for CO2 to return pre-human levels.
隨著動物群和植物群繁盛，地球的氣候會漸漸從數千年的人類影響中恢復。在三萬五千年之內，植物循環會清除掉最後僅存的鉛痕跡，工業革命留在地球土壤中的鉛，還要花六萬五千年，二氧化碳才能回到人類出現之前的狀態。
But even after several million years, humanity’s legacy lives on.Carved in unyielding granite, America’s Mt. Rushmore survives for 7.2 million years. The chemical composition of our bronze sculptures keeps them recognizable for over 10 million. And buried deep underground, the remnants of cities built on floodplains have been preserved in time as a kind of technofossil.
但即使是數百年之後，人類的遺產還是會存留著。美國拉什穆爾山上堅硬花崗巖的雕刻能夠存活七百二十萬年。我們的銅像，會因為其化學成份，在超過一千萬年之後仍然可辨視得出來。深埋在地底下，建在泛濫平原上的城市的遺蹟，未來會被保存下來成為某種技術化石。
Eventually, these traces, too, will be wiped from the planet’s surface.Humanity hasn’t always been here, and we won’t be here forever. But by investigating the world without us, perhaps we can learn more about the world we live in now.
最終，這些痕跡也還是會被從地球表面上抹除。人類並非一直存在於地球上，也不可能會永遠存在下去。但，藉由探究沒有人類的世界，也許我們能對我們現在所居住的世界了解更多。