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科学美国人60秒 SSS Ancient Mexican Metropolis Engaged in Hare-Raising Activity

时间:2017-03-03 08:40:37

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(单词翻译)

 

As humans developed civilizations in Eurasia and Northern Africa, they also domesticated1 animals for food and labor2: horses, cows, goats, pigs, sheep and a few others. But no evidence existed for the deliberate cultivation3 and breeding of animals in North or Central America—until now.

“So at this ancient city of Teotihuacan in particular, which is really one of the earliest urban cities in North America…”

Andrew Somerville of the University of California San Diego, talking about the metropolis4 that once existed some 30 miles northeast of present-day Mexico City.

“…previous excavations5 have found a lot of rabbits. But at one compound in particular they found more evidence that they were interacting with rabbits more intensively. There was a statue of a rabbit. There was evidence that maybe they were butchering them. And this compound, which is called Oztoyahualco, actually had almost twice as many rabbit bones relative to the other complexes at the city. So it did seem like something was different with this particular compound.”

Somerville and colleagues tested 134 rabbit bones at the 2,000-year-old site, as well as 13 contemporary samples. If the ancient rabbits fed on wild vegetation, the carbon isotopes6 in the bones would show evidence of what’s known as the C3 photosynthetic8 pathway. But the domesticated crops of that time, such as corn and cactus9 fruit, employ what’s called the C4 pathway—which leaves a different carbon isotope7 ratio in the bones.

“Fortunately we were able to actually show that rabbits from this compound did actually have higher carbon values, significantly higher carbon values. Which means that they did have significantly different diets from other rabbits within the city, and also significantly different diets than wild rabbits from around the region. Which is pretty strong evidence we say to show that they were actually being provisioned by humans, fed by humans, managed by humans.”

The research is in the journal PLoS ONE. [Andrew D. Somerville et al, Animal Management at the Ancient Metropolis of Teotihuacan, Mexico: Stable Isotope Analysis of Leporid (Cottontail and Jackrabbit) Bone Mineral]

It’s true that the carbon evidence could also be the result of the rabbits being trapped in corn fields, where they were scavenging. But the presence of the dedicated10 pen and the statue of a rabbit led the scientists to conclude that the animals were in fact being raised—which changes our understanding of New World cities.

“That is one of these assumptions about the new world—that they just didn't have as intensive relationships with animals. That husbandry, especially with mammals, wasn't as important of a factor in their organization and supporting these big cities. So what we're showing is that maybe they were just as intensive in some respects as these old world cities but they’re just less archaeologically11 visible. A rabbit leaves a much smaller footprint than a cow or a horse does.”

—Cynthia Graber


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1 domesticated Lu2zBm     
adj.喜欢家庭生活的;(指动物)被驯养了的v.驯化( domesticate的过去式和过去分词 )
参考例句:
  • He is thoroughly domesticated and cooks a delicious chicken casserole. 他精于家务,烹制的砂锅炖小鸡非常可口。 来自《简明英汉词典》
  • The donkey is a domesticated form of the African wild ass. 驴是非洲野驴的一种已驯化的品种。 来自《简明英汉词典》
2 labor P9Tzs     
n.劳动,努力,工作,劳工;分娩;vi.劳动,努力,苦干;vt.详细分析;麻烦
参考例句:
  • We are never late in satisfying him for his labor.我们从不延误付给他劳动报酬。
  • He was completely spent after two weeks of hard labor.艰苦劳动两周后,他已经疲惫不堪了。
3 cultivation cnfzl     
n.耕作,培养,栽培(法),养成
参考例句:
  • The cultivation in good taste is our main objective.培养高雅情趣是我们的主要目标。
  • The land is not fertile enough to repay cultivation.这块土地不够肥沃,不值得耕种。
4 metropolis BCOxY     
n.首府;大城市
参考例句:
  • Shanghai is a metropolis in China.上海是中国的大都市。
  • He was dazzled by the gaiety and splendour of the metropolis.大都市的花花世界使他感到眼花缭乱。
5 excavations 185c90d3198bc18760370b8a86c53f51     
n.挖掘( excavation的名词复数 );开凿;开凿的洞穴(或山路等);(发掘出来的)古迹
参考例句:
  • The excavations are open to the public. 发掘现场对公众开放。
  • This year's excavations may reveal ancient artifacts. 今年的挖掘可能会发现史前古器物。 来自辞典例句
6 isotopes 92848c3160703e48dc3b552ac6f54115     
n.同位素;同位素( isotope的名词复数 )
参考例句:
  • the many isotopes of carbon 碳的诸多同位素
  • Tritium is one of the mildest radioactive isotopes. 氚是最和缓的放射性同位素之一。 来自《简明英汉词典》
7 isotope isotope     
n.同位素
参考例句:
  • The isotope ratio is directly used for comparing oils or gases.同位素比率直接用于比较各种石油或天然气。
  • How to apply a radio isotope?如何运用放射性同位素?
8 photosynthetic 1f9a8b17a4e53d9a4fd0ed5147e2f5bd     
adj.光合的,促进光合作用的
参考例句:
  • In some plants photosynthetic products are stored in the form polyfructosans. 在有些植物中,光合作用产物是以多聚果糖的形式储藏。
  • Chlorotic or necrotic lesions were evidence of decreased photosynthetic tissues. 缺绿的或坏死的侵蚀斑便是减少了光合组织的证据。
9 cactus Cs1zF     
n.仙人掌
参考例句:
  • It was the first year that the cactus had produced flowers.这是这棵仙人掌第一年开花。
  • The giant cactus is the vegetable skycraper.高大的仙人掌是植物界巨人。
10 dedicated duHzy2     
adj.一心一意的;献身的;热诚的
参考例句:
  • He dedicated his life to the cause of education.他献身于教育事业。
  • His whole energies are dedicated to improve the design.他的全部精力都放在改进这项设计上了。
11 archaeologically 0f3d0d3dc95d8e0a135a1d07d1105c6d     
archaeology(考古学)的变形
参考例句:
  • An archaeologically valuable ancient tomb was unearthed in the underlying soil of this corn field. 这片玉米地下伏土层中出土了一个有考古价值的古墓。
  • The first chapter researchs archaeologically the formation and characters of English common law. 第一章对英国普通法的形成、特征和美国对英国普通法的继受进行了考古研究。

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