俄羅斯著名的狐貍馴化研究可能有幾個關鍵的缺陷

俄羅斯著名的狐貍馴化研究可能有幾個關鍵的缺陷

In 1959, the Soviet zoologist Dmitry Belyaev began selectively breeding silver foxes. Those least afraid of people were chosen to reproduce. His goal was to simulate the process that turned fierce ancient wolves into the dogs now known as our best friends.

1959年，蘇聯(lián)動物學家德米特里·別列耶夫開始有選擇地培育銀狐。那些最不怕人的人被選擇去繁衍后代。他的目標是模擬把兇猛的古代狼變成現(xiàn)在我們最好的朋友的狗的過程。

The experiment worked, famously well. In 10 generations, Belyaev's lineage of foxes became tame, seeking attention from people and wagging their tails when scientists approached.

這個實驗非常成功。經(jīng)過10代之后，Belyaev的狐貍家族變得溫順了，他們尋求人們的注意，當科學家靠近時，他們會搖尾巴。

But this wasn't the only way the foxes changed. In 1979, Belyaev noted that some of the foxes had begun to look different, developing curly tails, spotting on their coats and floppy, puppy-like ears.

但這并不是狐貍改變的唯一方式。1979年，Belyaev注意到一些狐貍開始看起來不同了，它們長出了卷曲的尾巴，皮毛上有斑點，耳朵耷拉著，像小狗一樣。

Later, other scientists began noticing some of these same traits in other domesticated species - pigs and goats, birds and fish - which seemed to point to a common genetic path that animals take as they change from wild to tame to domesticated.

后來，其他科學家開始注意到其他家養(yǎng)物種——豬、山羊、鳥和魚——也有一些相同的特征，這些特征似乎指向了動物從野生到馴養(yǎng)再到馴化的共同遺傳路徑。

This tantalizing notion, now known as domestication syndrome, was first put forward by Charles Darwin, and it has become integral to our understanding of how animal domestication works. But in a new paper, some scientists have challenged its accuracy - and, along the way, common beliefs about what domestication means.

這個誘人的概念，現(xiàn)在被稱為馴養(yǎng)綜合癥，是由查爾斯·達爾文首先提出的，它已經(jīng)成為我們理解動物馴養(yǎng)是如何運作的不可或缺的一部分。但在一篇新發(fā)表的論文中，一些科學家對其準確性提出了質(zhì)疑，同時也對馴化的普遍意義提出了質(zhì)疑。

The authors of the paper do not doubt that Belyaev was able to breed tamer foxes. But the Russian experiment fell short of proving the existence of domestication syndrome, they argue, because Belyaev's first foxes were far from wild, and there's no proof certain physical features are common to domesticated species.

這篇論文的作者并不懷疑Belyaev能夠培育出溫順的狐貍。但他們認為，俄羅斯的實驗未能證明馴化綜合癥的存在，因為Belyaev的第一批狐貍遠離野生環(huán)境，也沒有證據(jù)表明某些物理特征是馴化物種所共有的。

The common story line is that when you select on tameness in an animal species, a whole suite of other traits change in a predictable way, said Elinor Karlsson, a genomic scientist at the University of Massachusetts Medical School and senior author on the study. "And we just couldn't find convincing evidence for that."

“通常的情況是，當你選擇一個動物物種的馴養(yǎng)性時，一整套其他特征會以一種可預見的方式改變，”馬薩諸塞大學醫(yī)學院(University of Massachusetts Medical School)的基因組科學家、該研究的資深作者埃莉諾·卡爾森(Elinor Karlsson)說。“我們只是找不到令人信服的證據(jù)。”

A major problem is that Belyaev started with foxes that weren't wild, said Kathryn Lord, an evolutionary biologist at the University of Massachusetts Medical School and lead author of the paper, published Tuesday in the journal Trends in Ecology and Evolution. Genetic testing indicated they originated in eastern Canada, probably at a fur farm on Prince Edward Island, which means the animals were already on the path toward domestication.

馬薩諸塞大學醫(yī)學院(University of Massachusetts Medical School)進化生物學家洛德(Kathryn Lord)說，一個主要的問題是，Belyaev一開始用的狐貍不是野生的。洛德是這篇論文的第一作者，論文周二發(fā)表在《生態(tài)與進化趨勢》(Trends in Ecology and Evolution)雜志上?；驕y試表明，它們起源于加拿大東部，可能在愛德華王子島的一個毛皮農(nóng)場，這意味著這些動物已經(jīng)走上了馴化的道路。

There's also evidence that Canadian fur farmers were seeking to produce unusual pelt colors, including with white spotting, which might fetch higher prices. So some of the traits held up by Belyaev as evidence of the domestication syndrome may already have been present in his first batch of foxes.

也有證據(jù)表明，加拿大的毛皮養(yǎng)殖者正在尋求生產(chǎn)不尋常的毛皮顏色，包括白色斑點，這可能會賣到更高的價格。因此，Belyaev提出的一些作為馴化綜合癥證據(jù)的特征可能已經(jīng)在他的第一批狐貍中出現(xiàn)了。

And those foxes' tendency to produce white spots likely would have become greater when they arrived in Russia, because Belyaev started his experiment with a rather small population of 130 animals, Karlsson said.

Karlsson說，這些狐貍到達俄羅斯后，可能會產(chǎn)生更多的白斑，因為Belyaev的實驗開始時只有130只動物。

You can get very rapid changes in the frequency or the prevalence of a trait without having done a whole lot of work, just by making the population really, really small, she said.

她說:“你不需要做大量的工作，就可以讓一個特征的頻率或流行度發(fā)生非常迅速的變化，只需要讓這個群體變得非常非常小。”

The other wrinkle is that evidence for the suite of physical traits long said to be shared by dogs, goats, rabbits and other domesticated species is thin, the authors say.

作者說，另一個問題是，長期以來被認為是狗、山羊、兔子和其他家養(yǎng)物種共有的一系列生理特征的證據(jù)很少。

For instance, it's commonly said that domesticated animals have curlier, more upright tails - the difference between a Siberian husky's and a gray wolf's. But Lord and her colleagues found no conclusive evidence that domesticated dogs hold their tails differently from wolves, foxes or other wild canids. They also found little documentation of these traits for other animals.

例如，人們常說家養(yǎng)動物的尾巴更卷曲、更直立——這就是西伯利亞哈士奇和灰狼的區(qū)別。但是洛德和她的同事們沒有找到確鑿的證據(jù)證明家犬的尾巴與狼、狐貍或其他野狗不同。他們還發(fā)現(xiàn)，關于其他動物這些特征的記錄也很少。

None of this matters much to how most of us relate to our dogs and cats (or pigs and goats). But the challenge to common wisdom about how those animals came to be has caused waves in the community of domestication scholars - and gotten a mixed reception.

這些都與我們大多數(shù)人如何與我們的狗和貓(或豬和山羊)相處無關。但是，對于這些動物是如何進化而來的常識的挑戰(zhàn)，已經(jīng)在馴養(yǎng)學者的圈子里引起了波瀾，并得到了褒貶不一的評價。

The fox experiment is the most celebrated one in studies of domestication, yet details of it have never been fully published or explained, much less critically assessed, said Marcelo Sánchez-Villagra, a paleobiologist at the University of Zurich who has studied domestication syndrome. "This paper to me shows that new, better designed experiments on domestication - of several kinds of animals - are needed to advance the field forward."

“狐貍實驗是馴養(yǎng)研究中最著名的一個，但它的細節(jié)從未被完全公布或解釋，更沒有經(jīng)過嚴格的評估，”研究馴養(yǎng)綜合癥的蘇黎世大學(University of Zurich)古生物學家馬塞洛桑切斯-維拉格拉(Marcelo Sanchez-Villagra)說。“對我來說，這篇論文表明，要推動這一領域向前發(fā)展，需要對幾種動物的馴化進行新的、設計更好的實驗。”