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This is Scientific American — 60-Second Science. I'm Christopher Intagliata.

这里是科学美国人——60秒科学。我是克里斯托弗·因塔利亚塔。

Abandoned pueblos² are scattered³ throughout the southwestern U.S. And at many, archaeologists have uncovered a curious artifact: the skeletons of scarlet⁴ macaws. The birds' bright red feathers are known to have been an important status symbol, a signifier of prestige, for people throughout the American tropics and the southwest... both in the ancient world and today.

被遗弃的印第安人村庄散布在美国西南部地区。考古学家在许多村庄都发现了一种奇怪的人工制品：五彩金刚鹦鹉的骨架。我们知道，这种鸟的鲜红色羽毛一直是重要的身份象征和威望象征，无论是古代还是如今，对整个美国热带地区和西北部地区来说都是如此。

But macaws are a tropical bird, whose range never extended north of today's U.S.-Mexico border. So how did the pueblo¹ people obtain the birds?

但金刚鹦鹉是热带鸟类，其活动范围从未扩大至今天的美国-墨西哥边境以北。那印第安人是如何得到这些鹦鹉的？

To examine the birds' origin, scientists sequenced mitochondrial DNA⁵ found within macaw bones from two sites in New Mexico: Chaco Canyon⁶ and the Mimbres region. Turns out, nearly three quarters of the birds had identical mitochondrial genome sequences—meaning the ancient birds came from the same maternal⁷ line. That suggests they were all the products of a breeding operation, perhaps in modern-day northern Mexico, rather than a random⁸ collection of wild-caught birds.

为了调查这种鹦鹉的来历，科学家对金刚鹦鹉骨骼中发现的线粒体DNA进行了测序，实验所用鹦鹉骨骼来自新墨西哥州查科峡谷和明布雷斯地区的两处遗址。结果表明，近四分之三的鹦鹉拥有相同的线粒体基因组序列，这意味着这些古代鹦鹉来自同一母系。这表明，它们都是人工饲养的后代，繁育地点可能位于今天的墨西哥北部地区，而不是在野外随机捕获的鹦鹉。

"If it was just more random, you know, forgive the word, 'plucking,' random macaws from the environment, we would have expected to see a type of diversity that you'd see in the wild."

“如果说是更为随机地从环境中‘抓'鹦鹉，原谅我用‘抓'这个词，那我们会发现像野生环境一样复杂的测序多样性。”

Richard George, a PhD candidate in anthropology⁹ at Penn State.

宾夕法尼亚州立大学在读人类学博士理查德·乔治说到。

"And so when we took our results and compared them to macaws distributed throughout the historic and modern ranges, the results were more analogous¹⁰ to other species of animals that were being bred, like turkeys or dogs or pigs."

“当我们将研究结果与金刚鹦鹉古今分布范围进行对比时，发现结果与火鸡、狗或猪等其它饲养动物更为相似。”

The details are in the Proceedings¹¹ of the National Academy of Sciences.

这项研究的详细内容刊登在《美国国家科学院院刊》上。

The discovery adds an additional layer of complexity¹² to our understanding of Southwestern and Mesoamerican cultures: they had the sophistication to breed and manage the distribution of these exotic birds. And it's an example, too, of how modern sequencing technology can unlock historical and cultural secrets, that sat waiting in these bones for more than 800 years.

这一发现使我们对西南部和美索美洲文化的理解又增加了一层难度：他们繁育这些外来鹦鹉并管理其分布的能力相当成熟。这也是一个例证，证明了现代测序技术可以揭开在这些鹦鹉骨骼中隐藏了800多年的历史和文化谜团。

Thanks for listening for Scientific American — 60-Second Science. I'm Christopher Intagliata.

谢谢大家收听科学美国人——60秒科学。我是克里斯托弗·因塔利亚塔。