来源：《新科学家》
原文刊登日期：2022年6月6日
The earliest domestic chickens we have ever found lived no earlier than 3670 years ago, suggesting the world’s most common domestic animal has a far shorter history than previously thought. What is more, these birds don’t appear to have been raised for their meat, making it unclear what drove the domestication process.
我们发现，最早的家鸡出现的时间不会早于3670年前，这表明世界上最常见的家禽的历史比我们之前认为的要短得多。更重要的是，这些鸟类似乎不是为了吃肉而被饲养的，这使得人们不清楚是什么推动了驯化过程。
The chickens alive today descend from a wild bird native to South-East Asia called the red junglefowl, but exactly when domestication occurred was unclear. Some researchers have estimated that the first domestic chicken lived more than 6000 years ago, while others claim to have found chicken bones at 10,000-year-old archaeological sites.
现存的鸡是一种原产于东南亚的野生鸟类红原鸡的后代，但究竟是什么时候被驯化的还不清楚。一些研究人员估计，最早的家鸡生活在6000多年前，而另一些研究者声称在1万年前的考古遗址发现了鸡骨头。
Ophélie Lebrasseur at the Centre for Anthropobiology and Genomics of Toulouse in France has co-authored a comprehensive analysis of the evidence. It concludes that domestic chickens make their first clear appearance in the archaeological record much later – between 1650 BC and 1250 BC at a site called Ban Non Wat in central Thailand.
法国图卢兹人类生物学和基因组学中心的奥菲莉·勒布拉瑟尔与他人合作，对证据进行了全面分析。其结论是，家鸡在考古记录中首次出现的时间要晚得多——在公元前1650年至1250年之间，在泰国中部一个名为班诺洼的遗址。
“It’s the earliest irrefutable evidence,” says Lebrasseur. Not only are chicken bones superabundant at Ban Non Wat, there is also evidence that people were buried with the birds, which she says makes a domestic relationship clear.
“这是最早的无可辩驳的证据，”勒布拉瑟尔说。在班诺洼，不仅有大量的鸡骨头，还有证据表明人们与鸡葬在一起，她说，这说明了一种驯养关系。
One reason why researchers had previously suggested domestication occurred much earlier is that chicken bones are easily confused with those of other birds. Another reason is that burrowing animals can displace small chicken bones underground so that they end up in older, deeper layers of dirt, which can lead archaeologists to assume the bones are ancient.
研究人员先前认为鸡的驯化发生得更早的一个原因是，鸡的骨头很容易与其他鸟类的骨头混淆。另一个原因是，穴居动物可以把鸡的小块骨头移到地下，这样它们就会留在更古老、更深的泥土层中，这可能会让考古学家认为这些骨头是古老的。
In a second study, Julia Best at Cardiff University, UK, and her colleagues showed how this process can confuse archaeologists. They radiocarbon-dated 23 chicken bones from several archaeological sites across Europe and north-west Africa, and found 18 of them were younger than previously thought.
在第二项研究中，英国卡迪夫大学的朱莉娅·贝斯特和她的同事们展示了这个过程是如何迷惑考古学家的。他们对来自欧洲和非洲西北部几个考古遗址的23块鸡骨头进行了放射性碳年代测定，发现其中18块比之前认为的年代要晚。
Lebrasseur’s team suspects chicken domestication might have been triggered by the appearance of cereal farming in South-East Asia. “This created a more open, less tree-covered environment, which is actually an environment where red junglefowl thrive,” she says. “And they could have fed on the waste from human societies.”
勒布拉瑟尔的研究小组怀疑，鸡的驯化可能是由东南亚谷物种植的出现引发的。她说：“这创造了一个更开放、更少树木覆盖的环境，这实际上是一个有利于红原鸡繁衍生息的环境。它们可能以人类社会的废物为食。”
This suggests the birds were attracted to human settlements, and natural selection might have played a role in turning them into domestic chickens. Dog domestication is thought to have occurred in a broadly similar way.
这表明红原鸡被人类居住地所吸引，自然选择可能在将它们变成家鸡方面发挥了作用。狗的驯化被认为是以一种大致相似的方式发生的。
Why humans would have encouraged chicken domestication is less clear. Best and her colleagues found little evidence that chickens were butchered for their meat when they were first introduced to Europe, and Lebrasseur thinks this indicates domestication wasn’t driven by a desire for meat. She says we still don’t really understand what drove the process.
人类为什么会促进鸡的驯化还不清楚。贝斯特和她的同事们发现，几乎没有证据表明，当鸡第一次被引入欧洲时，它们被用来屠宰吃肉。勒布拉瑟尔认为，这表明驯化不是由对肉的渴望驱动的。她说，我们仍然不明白是什么推动了这一过程。