關于古猿露西的有趣事實

關于古猿露西的有趣事實

One day during the Pliocene Epoch, a young adult ape died in the Awash Valley of East Africa. She was soon forgotten, and wouldn't be seen again for 3.2 million years. During that time, her species went extinct, new apes appeared across Africa and some evolved huge brains, helping them basically conquer the planet.

上新世的一天，東非的阿瓦什山谷里，一只年輕的成年猿死了。她很快就被遺忘了，320萬年后再也沒有出現(xiàn)過。在那段時間里，她的物種滅絕了，非洲各地出現(xiàn)了新的類人猿，一些類人猿進化出了巨大的大腦，幫助它們基本上征服了地球。

Lucy belonged to the extinct species Australopithecus afarensis, portrayed here in a sculptor's rendering. (Photo: Dave Einsel/Getty Images)

Then, 3.2 million years after that fateful day, two of these brainy apes finally stumbled across her skeleton in what's now Ethiopia. Realizing they'd found something historic, they began to carefully dig her out of the desert.

然后，在那個災難性的日子過去320萬年后，這兩只聰明的猿類終于在現(xiàn)在的埃塞俄比亞偶然發(fā)現(xiàn)了她的骨架。意識到他們發(fā)現(xiàn)了一些具有歷史意義的東西，他們開始小心翼翼地把她從沙漠中挖出來。

First, however, they gave their long-lost relative a name: "Lucy."

然而，他們首先給他們失散多年的親戚起了個名字:“露西”。

Here are a few interesting facts you may not know about Lucy, from groundbreaking revelations about her life to random trivia about her name(s):

以下是一些你可能不知道的關于露西的有趣事實，從對她生活的突破性發(fā)現(xiàn)到關于她名字的隨機瑣事:

1. She walked on two feet, but also hung out in trees.

她用兩只腳走路，但也在樹上閑逛。

New research supports the idea that Lucy walked upright similar to modern humans, but also spent a lot of time in trees — as implied by this exhibit from the Smithsonian Museum of Natural History. (Photo: Tim Evanson [CC BY-SA 2.0]/Flickr)

Lucy lived at a pivotal time for human-like apes known as hominins. Her species was transitional, with key traits of earlier apes as well as later humans. (It's worth noting, though, the "missing link" concept is a fallacy. It's based on an outdated belief that evolution is linear, and on a misinterpretation of inevitable gaps in the fossil record.)

露西生活在人類類人猿的關鍵時期。她的物種是過渡性的，具有早期猿類和晚期人類的關鍵特征。(不過值得注意的是，“缺失環(huán)節(jié)”的概念是一種謬論。它基于一種過時的信念，即進化是線性的，以及對化石記錄中不可避免的空白的誤解。

Lucy's skeleton offers several signs of bipedalism, or walking on two feet. (Photo: Juan Aunion/Shutterstock)

Lucy walked on two feet, a major step in human evolution. We know this from several clues in her bones, such as the angle of her femur in relation to knee-joint surfaces — an adaptation that helps bipedal animals balance while walking. Her knee joints also show signs of carrying her full body weight, rather than sharing the burden with her front limbs, and various other indications have been found in her pelvis, ankles and vertebrae. Still, her skeleton couldn't have moved quite like ours does, and her big, chimp-like arms suggest she hadn't yet abandoned the trees.

露西用兩只腳走路，這是人類進化的重要一步。我們從她骨頭上的一些線索知道這一點，比如她股骨與膝關節(jié)表面的角度——一種幫助兩足動物在行走時保持平衡的適應性。她的膝關節(jié)也顯示出承載全身重量的跡象，而不是與前肢共同承擔這個負擔，她的骨盆、腳踝和脊椎也有各種其他跡象。盡管如此，她的骨架不可能像我們的骨架那樣移動得那么快，而她那巨大的黑猩猩般的手臂表明，她還沒有拋棄樹木。

2. She made us rethink the rise of big human brains.

她讓我們重新思考人類大腦的崛起。

The brains of Lucy's species, Australopithecus afarensis, were about one-third the size of a modern human brain. Pictured above is an endocast, a brain model based on the space in an animal's cranial vault. (Photo: Tim Evanson [CC BY-SA 2.0]/Flickr)

Before Lucy, it was widely believed that hominins evolved big brains first, and then became bipedal later. Lucy, however, was clearly built for bipedal walking — an extremely rare adaptation for mammals — and yet her skull only had space for a brain about the size of a chimpanzee's. Her cranial capacity was less than 500 cubic centimeters, or roughly one-third as big as that of a modern human.

在露西之前，人們普遍認為人類首先進化出大腦，然后才進化成兩足動物。然而，露西顯然是為兩足行走而生的——這是哺乳動物極其罕見的適應能力——然而，她的頭骨卻只有黑猩猩大腦大小的空間。她的腦容量不足500立方厘米，大約是現(xiàn)代人的三分之一。

3. She was an adult, but only stood as tall as a modern 5-year-old.

她是個成年人，但身高只有現(xiàn)代5歲孩子的水平。

A human child poses next to the skeleton of an adult Australopithecus afarensis. (Photo: James St. John [CC BY 2.0]/Flickr)

Lucy's brain may have been smaller than ours, but to be fair, so was her whole body. She was a fully grown young adult when she died, yet stood just 1.1 meters (3.6 feet) tall and weighed about 29 kilograms (64 pounds).

露西的大腦可能比我們的小，但平心而論，她的整個身體也是如此。她去世時已經(jīng)是一個完全成年的年輕人，但身高只有1.1米(3.6英尺)，體重約29公斤(64磅)。

4. She may have died by falling out of a tree.

她可能是從樹上掉下來而死的。

This illustration shows a leading — but not universally accepted — theory about Lucy's death. It's from a 2016 study that concludes she suffered fatal injuries from a fall, 'probably out of a tree.' (Image: John Kappelman/UT-Austin)

For all we've learned about Lucy's life over four decades, her death has remained mysterious. Her skeleton doesn't show signs of gnawing by carnivores or scavengers (aside from a single tooth mark on one of her bones), so scientists doubt she was killed by a predator. Otherwise, though, they've been stumped.

40多年來，我們對露西的生活了解甚多，但她的死仍然是個謎。她的骨骼沒有被食肉動物或食腐動物咬傷的跡象(除了骨頭上有一顆牙印)，所以科學家懷疑她是被食肉動物咬死的。然而，在其他方面，他們卻被難倒了。

Then, in August 2016, a team of U.S. and Ethiopian researchers announced a break in Lucy's cold case. Their study, published in the journal Nature, concluded her death "can be attributed to injuries resulting from a fall, probably out of a tall tree." They used high-resolution CT scans to make 35,000 virtual "slices" of her skeleton, one of which showed something odd. Lucy's right humerus had a type of fracture uncommon in fossils: a series of sharp, clean breaks with bone fragments and slivers still in place. Along with other, less severe fractures at the left shoulder and elsewhere, this is consistent with a long fall in which the victim tries to break the impact by extending an arm before landing.

然后，2016年8月，一個由美國和埃塞俄比亞研究人員組成的團隊宣布，露西的死亡之謎出現(xiàn)了轉(zhuǎn)機。他們的研究發(fā)表在《自然》雜志上，結(jié)論是她的死亡“可能是由于從一棵大樹上摔下來而受傷。”他們使用高分辨率CT掃描技術(shù)對她的骨骼進行了35000次虛擬“切片”，其中一次顯示出了一些奇怪的現(xiàn)象。露西的右肱骨有一種在化石中罕見的骨折類型:一系列鋒利的、干凈的骨折，骨頭碎片和碎片仍在原地。與其他左肩和其他地方不太嚴重的骨折一樣，這與長時間的墜落相一致，受害者試圖在著陸前伸出手臂來打破撞擊。