《那些古怪又讓人憂心的問題》第6期:紐約式時間機器(1)
NEW YORK–STYLE TIME MACHINE
NEW YORK-STYLE TIME MACHINE Q. I assume when you travel back in time you end up at the same spot on the Earth's surface. At least, that's how it worked in the Back to the Future movies. If so, what would it be like if you traveled back in time, starting in Times Square, New York, 1000 years? 10,000 years? 100,000 years? 1,000,000 years? 1,000,000,000 years? What about forward in time 1,000,000 years?
Q．我總認爲當你回到過去時，你會到達和穿越前同一位置的地方，至少在電影《回到未來》中是這樣的。如果真是如此，那麼站在紐約的時代廣場向前穿越1千年會怎樣？1萬年呢？10萬年呢？100萬年呢？10億年呢？如果是向未來穿越100萬年呢？ ——馬克.德特蘭1000 years back
1千年前
Manhattan has been continuously inhabited for the past 3000 years, and was first settled by humans perhaps 9000 years ago.
在過去3千年間，曼哈頓地區就一直有人居住。最早來此定居的人大約是在9千年前。In the 1600s, when Europeans arrived, the area was inhabited by the Lenape people.1 The Lenape were a loose confederation of tribes who lived in what is now Connecticut, New York, New Jersey, and Delaware.
歐洲人於17世紀來到這裏，那時居住在此的還是勒納佩人。1勒納佩人是一個由衆多部落組成的鬆散聯盟，住在如今的康涅狄格、紐約、新澤西以及特拉華地區。A thousand years ago, the area was probably inhabited by a similar collection of tribes, but those inhabitants lived half a millennium before European contact. They were as far removed from the Lenape of the 1600s as the Lenape of the 1600s are from the modern day.
1千年前，這個地區很有可能還居住着一羣相似的部落聯合體，但是此時距離歐洲人初次抵達還有500年。他們和17世紀勒納佩人的距離，就像勒納佩人和現代人的距離一樣遠。To see what Times Square looked like before a city was there, we turn to a remarkable project called Welikia, which grew out of a smaller project called Mannahatta. The Welikia project has produced a detailed ecological map of the landscape in New York City at the time of the arrival of Europeans.
要想知道1千年前連城市都沒有的時代廣場看上去是什麼樣，我們就要藉助一個偉大的項目：威利極亞（Welikia）2。它是由一個更小的項目——曼納哈塔（Mannahatta）發展而來的。威利極亞計劃已經繪製出了歐洲人第一次到達紐約城時那裏的詳細生態地貌圖。The interactive map, available online at , is a fantastic snapshot of a different New York. In 1609, the island of Manhattan was part of a landscape of rolling hills, marshes, woodlands, lakes, and rivers.
在上，我們可以看到互動式的地圖，一窺紐約以前的美景。1609年，曼哈頓島還是由起伏的山脈、沼澤、林地、湖泊和河流形成的地景的一部分。The Times Square of 1000 years ago may have looked ecologically similar to the Times Square described by Welikia. Superficially, it probably resembled the old-growth forests that are still found in a few locations in the northeastern US. However, there would be some notable differences.
1千年前的時代廣場的樣子應該和威利極亞中描述的差不多。表面上看，可能會覺得它有點像如今生長在美國東北部的那些古老森林，但兩者還是有一些顯著差異。There would be more large animals 1000 years ago. Today's disconnected patchwork of northeastern old-growth forests is nearly free of large predators; we have some bears, few wolves and coyotes, and virtually no mountain lions. (Our deer populations, on the other hand, have exploded, thanks in part to the removal of large predators.)
1千年前的時代廣場有更多大型動物。如今在美國東北地區零碎分佈的小片古老森林裏，已經幾乎見不到大型食肉動物了。那裏還有一些熊、少量的狼和郊狼，幾乎沒有山獅。（不過鹿羣的數量暴增，部分原因是大型食肉動物都消失了。）The forests of New York 1000 years ago would be full of chestnut trees. Before a blight passed through in the early twentieth century, the hardwood forests of eastern North America were about 25 percent chestnut. Now, only their stumps survive.
1千年前的紐約森林本應滿是慄樹。20世紀初期的枯萎病發生之前，北美東部的硬木林曾有四分之一是慄樹，但現在活下來的只有樹樁了。You can still come across these stumps in New England forests today. They periodically sprout new shoots, only to see them wither as the blight takes hold. Someday, before too long, the last of the stumps will die.
現在在新英格蘭的森林，你還能看到那些樹樁。它們會間歇性地生出新芽來，但不久就會因枯萎病而死去。用不了多久，最後的慄樹樹樁也會死去。Wolves would be common in the forests, especially as you moved inland. You might also encounter mountain lions2,3,4,5,6 and 7passenger pigeons.
在森林中狼很常見，隨着你往內陸行進還會越來越多。你可能還會在內陸地區的森林裏遇上山獅3，4，5，6，7和旅鴿。There's one thing you would not see: earthworms. There were no earthworms in New England when the European colonists arrived. To see the reason for the worms' absence, let's take our next step into the past.
但有一種生物你不會看到：蚯蚓。當歐洲殖民者第一次來到新英格蘭地區時，那裏還沒有蚯蚓。要想知道其中的原因，我們將視線移到更早的時期。10,000 years back
1萬年前The Earth of 10,000 years ago was just emerging from a deep cold period.
一萬年前的地球剛從冰河期裏走出來。The great ice sheets that covered New England had departed. As of 22,000 years ago, the southern edge of the ice was near Staten Island, but by 18,000 years ago it had retreated north past Yonkers.8 By the time of our arrival, 10,000 years ago, the ice had largely withdrawn across the present-day Canadian border.
此前覆蓋新英格蘭的大冰蓋剛剛消退。2.2萬年前，冰蓋的南端在斯塔頓島附近，但在1.8萬年前，冰蓋向北退到了楊克斯以北。9到了1萬年前，大部分冰蓋已經後退到如今的加拿大邊境以北了。The ice sheets scoured the landscape down to bedrock. Over the next 10,000 years, life crept slowly back northward. Some species moved north faster than others; when Europeans arrived in New England, earthworms had not yet returned.
冰蓋的消退抹去了基岩以上的所有東西。在之後的1萬年裏，生命開始漸漸轉移回來。一些物種向北移動的速度比其他物種快，當歐洲人到達新英格蘭時，蚯蚓還沒回到那裏呢。As the ice sheets withdrew, large chunks of ice broke off and were left behind.
隨着冰蓋的消退，一部分大冰塊從整體上脫落下來，就這樣遺留在地面上。When these chunks melted, they left behind water-filled depressions in the ground called kettlehole ponds. Oakland Lake, near the north end of Springfield Boulevard in Queens, is one of these kettlehole ponds. The ice sheets also dropped boulders they'd picked up on their journey; some of these rocks, called glacial erratics, can be found in Central Park today.
當這些冰塊融化後，產生的水填滿了地面上的低窪處，形成了所謂的鍋穴湖。位於昆士蘭的斯普林菲爾德大道北部盡頭處的奧克蘭湖就是一個鍋穴湖。撤退的冰蓋還會留下形成期間夾雜的卵石，這些石頭被稱爲冰川漂礫，如今在中央公園還能看到。Below the ice, rivers of meltwater flowed at high pressure, depositing sand and gravel as they went. These deposits, which remain as ridges called eskers, crisscross the landscape in the woods outside my home in Boston. They are responsible for a variety of odd landforms, including the world's only vertical U-shaped riverbeds.
在冰川下，融水形成的河流在高壓下流動，在所經之處堆積起大量沙石。這些沉積物形成了所謂的“冰河沙堆”（eskers）的脊，在現今我位於波士頓的家旁邊的樹林處縱橫交錯。很多奇奇怪怪的地形都是由這種現象造成的，包括世界上僅存的垂直U形谷河牀。100,000 years back
10萬年前The world of 100,000 years ago might have looked a lot like our own.9 We live in an era of rapid, pulsating glaciations, but for 10,000 years our climate has been stable10 and warm.
10萬年前的世界看起來可能和現在的世界更加相像。10a我們生活的時代裏充滿了快速交替的冰期，但在過去的1萬年裏，我們的氣候一直保持穩定11和溫暖。A hundred thousand years ago, Earth was near the end of a similar period of climate stability. It was called the Sangamon interglacial, and it probably supported a developed ecology that would look familiar to us.
10萬年前，地球正處在一個相似的氣候穩定期末端，這個時期被稱爲桑加蒙間冰期。那時可能也有一個像我們現在這樣高度發達的生態系統。The coastal geography would be totally different; Staten Island, Long Island, Nantucket, and Martha's Vineyard were all berms pushed up by the most recent bulldozer-like advance of the ice. A hundred millennia ago, different islands dotted the coast.
不過那時的海岸地質和現在完全不同，斯塔頓島、長島、楠塔基特島和馬薩葡萄園島都是被最近一次的冰川像推土機一樣推擠而成的坡臺。在10萬年前，海岸附近是另一批島嶼。Many of today's animals would be found in those woods-birds, squirrels, deer, wolves, black bears-but there would be a few dramatic additions. To learn about those, we turn to the mystery of the pronghorn.
那時的叢林裏可以找到許多現在的動物——比如鳥類、松鼠、鹿、狼、黑熊，除此以外還有一些很神奇的物種。要想了解這些生物，我們首先來看看謎一般的叉角羚。The modern pronghorn (American antelope) presents a puzzle. It's a fast runner-in fact, it's much faster than it needs to be. It can run at 55 mph, and sustain that speed over long distances. Yet its fastest predators, wolves and coyotes, barely break 35 mph in a sprint. Why did the pronghorn evolve such speed?
現代的叉角羚（美洲羚羊）仍然是一個謎。它們能跑得飛快，速度遠比生存所需的最高速度更快。它們能以每小時88千米的速度飛奔，並且能在很長一段距離內保持這個速度。而它們跑得最快的捕食者狼和郊狼在極速時也只能勉強突破每小時56千米。那麼叉角羚爲什麼會進化出這麼快的速度呢？The answer is that the world in which the pronghorn evolved was a much more dangerous place than ours. A hundred thousand years ago, North American woods were home to Canis dirus (the dire wolf), Arctodus (the short-faced bear), and Smilodon fatalis (sabre-toothed cat), each of which may have been faster and deadlier than modern predators. All died out in the Quaternary extinction event, which occured shortly after the first humans colonized the continent.
答案在於叉角羚進化時所處的環境遠比現在的環境更加危險。10萬年前，北美叢林是恐狼、短面熊和劍齒虎的家園，它們之中的任何一種都可能比現代捕食者跑得更快，也更加致命。不過它們都在第四紀滅絕事件（即冰河時期滅絕事件）中滅亡了，在此之前剛有人類來到美洲。If we go back a little further, we will meet another frightening predator.
如果我們把視線再往前移，就會看到更可怕的捕食者。
