取物的意愿可能是狼祖先種群中存在的狼的特征

取物的意愿可能是狼祖先種群中存在的狼的特征

Some wolf puppies are unexpectedly willing to play fetch, according to scientists who saw young wolves retrieve a ball thrown by a stranger and bring it back at that person's urging.

據(jù)科學(xué)家稱，一些狼出人意料地愿意玩接球游戲，他們看到小狼群撿到一個陌生人扔的球，然后在那個人的催促下把球帶回來。

This behavior wouldn't be surprising in a dog. But wolves are thought to be less responsive to human cues because they haven't gone through thousands of years of domestication.

這種行為在狗身上并不奇怪。但是狼被認(rèn)為對人類的暗示反應(yīng)較慢，因為它們沒有經(jīng)過數(shù)千年的馴化。

Exactly how dogs emerged from a now-extinct population of ancient wolves is a mystery. Wolves are large, dangerous carnivores, and yet they were the first animals that humans tamed. More than 15.000 years ago, when humans were still hunter-gatherers, this large predator somehow began cozying up to people, eventually becoming their "best friend."

狗是如何從現(xiàn)已滅絕的古狼種群中進(jìn)化而來的，這是個謎。狼是大型、危險的食肉動物，但它們是人類最早馴化的動物。15000多年前，當(dāng)人類還是采集狩獵人的時候，這種大型食肉動物不知怎么地開始與人類親近，最終成為他們“最好的朋友”。

To try to get clues about how that happened, scientists such as Christina Hansen Wheat of Stockholm University in Sweden have been studying the differences between dogs and modern wolves. As part of her work, she raised litters of wolf puppies, feeding them and acclimating them to her presence but not playing with them or training them.

為了弄清楚這是如何發(fā)生的，瑞典斯德哥爾摩大學(xué)的克里斯蒂娜·漢森·麥特等科學(xué)家一直在研究狗和現(xiàn)代狼的區(qū)別。作為工作的一部分，她飼養(yǎng)了一窩小狼崽，喂養(yǎng)它們，讓它們適應(yīng)她的存在，但不與它們玩?；蛴?xùn)練它們。

At the age of 8 weeks, the wolf pups were put through a series of standard behavior tests that were administered by a person the wolves had never met.

在8周大的時候，狼崽們接受了一系列的標(biāo)準(zhǔn)行為測試，這些測試是由狼從沒見過的人進(jìn)行的。

This set of tests is normally used by dog breeders, says Hansen Wheat, to assess how their puppies act in social situations. "The fetching test just happened to be part of this test.

漢森·麥特說，這組測試通常被狗狗飼養(yǎng)者用來評估幼犬在社交場合的表現(xiàn)。“抓取測試只是這個測試的一部分。

It wasn't something we were targeting at all," she says. The person conducting the test threw a tennis ball and urged the wolf puppy to bring it back. Two litters of puppies utterly failed to do this, surprising the scientists not at all.

這根本不是我們的目標(biāo)，”她說。進(jìn)行測試的人扔了一個網(wǎng)球，并催促小狼把它帶回來。兩窩小狼完全沒有做到這一點，這讓科學(xué)家們一點也不驚訝。

"There's some hypotheses out there that the ability to understand human social cues is a unique dog trait, a trait that arose after domestication had been initiated," Hansen Wheat explains, so fetching on command is not a behavior expected in wolves.

“有一些假說認(rèn)為，理解人類社會暗示的能力是狗的一種獨(dú)有特征，這種特征是在馴化開始后產(chǎn)生的，”漢森·麥特解釋說，因此，在狼中，按指令取物并不是一種預(yù)期的行為。

But then a third litter went through the tests. And as she watched through a window, one of the wolf puppies went for the ball and returned it to the tester, according to a report in the journal iScience.

但是第三窩小狼通過了測試。據(jù)《科學(xué)》雜志上的一篇報道稱，當(dāng)她透過窗戶觀看時，一只小狼崽撲向球，并把球還給了測試者。

"When I saw the first puppy fetch — I still get goosebumps when I talk about this — it was such a surprise," Hansen Wheat says. "It wasn't just one puppy, it was actually three of them. That was very exciting."

漢森·麥特說:“當(dāng)我看到第一只小狼叼走的時候——說到這里我還是會起雞皮疙瘩——這真是個驚喜。”“它不只是一只小狼，實際上是三只。這非常令人興奮。”

Because three of the 13 tested wolf puppies spontaneously did this, a willingness to fetch might not be a dog trait, she says. Instead, it might be a wolf trait that existed in the ancestral wolf populations.

她說，因為13只接受測試的小狼崽中有3只是自發(fā)地這樣做的，所以取物的意愿可能不是狗的特征。相反，這可能是存在于狼祖先種群中的狼的特征。

"It might have been something that we have tried to select upon during early domestication," Hansen Wheat says. "Wolf puppies doing this during early stages of domestication might have had a selective advantage, if they managed to establish a connection to our forefathers."

“這可能是我們在早期馴化過程中試圖選擇的東西，”Hansen Wheat說。“如果它們能與我們的祖先建立聯(lián)系的話，小狼崽在馴化的早期階段這樣做可能有選擇性優(yōu)勢。”

She notes that researchers who work with wolves typically have few animals to test. That means scientists simply might not have enough wolves to detect rare traits, making it hard to see variations as they attempt to compare wolves with dogs.

她指出，研究狼的研究人員通常沒有什么動物可以測試。這意味著，科學(xué)家們可能沒有足夠的狼來發(fā)現(xiàn)罕見的特征，這使得他們在試圖比較狼和狗時很難發(fā)現(xiàn)變異。