?In the most recent podcast we discussed how baby bats learn their calls from all the other bats in their crowded colonies. And we mentioned in passing that songbirds usually get tutored directory from their dads. So, how does that avian system work?在最新發(fā)布的一期播客中,我們討論了蝙蝠寶寶們是如何在擁擠的蝙蝠群中學(xué)習(xí)發(fā)聲的。其中提到了,在通常情況下,鳴禽會直接從父親那里得到指導(dǎo)。那么,在它們之間,這種‘學(xué)習(xí)’系統(tǒng)是如何運(yùn)作的呢?
? 撰文/播音:克里斯多夫·利亞塔(Christopher Intagliata) 翻譯:曲薈龍 審校:許楠
? "At about 25 days, the father starts singing directly to the juvenile." David Mets, a geneticist at the University of California San Francisco. "That is the onset of what's called the sensory phase of learning. Where they incorporate information from their environment." “在出生后25天左右,雄鳥便開始對向幼鳥鳴叫。”加州大學(xué)舊金山分校的遺傳學(xué)家大衛(wèi)·梅茨這樣說,“這是學(xué)習(xí)過程中感知階段的開始,在這一階段中,幼鳥們從周圍環(huán)境中獲得信息。” What Mets and his team wanted to know was how much of a baby bird's future musicality is influenced by that tutoring…an environmental factor…and how much is written in their genes. So they studied Bengalese finches.. which sing like this. <> 幼鳥的樂感,有多少源于雄鳥對其的指導(dǎo),又有多少是受到環(huán)境因素的影響,還有多少是由其基因?qū)е?,這正是梅茨及其團(tuán)隊想要了解的問題。他們選取孟加拉雀作為研究對象,它們的鳴叫聲是這樣。 <雀鳴1 > The tempo of that song appears to vary, according to a finch's genetics. So they tried training baby finches, with different genetic tendencies - fast, medium or slow singing - on a synthetic finch song, made from a library of different types of song syllables. "Tonal downward sweeps,?you know. Or sort of broadband noisy ones, like sshhhh." 孟加拉雀鳴叫的節(jié)奏聽起來有所不同,這取決于它們的基因。根據(jù)幼雀的基因譜,人類可以將它們分為快節(jié)奏、中等節(jié)奏和慢節(jié)奏三個不同的種類。實驗團(tuán)隊嘗試訓(xùn)練這些基因譜不同的幼雀來演奏一場雀類大合唱——這場大合唱包含著不同的音節(jié)。這其中有像吹口哨那樣逐漸下降的音調(diào),也有像“sshhhh”那樣寬頻的雜音。 But when baby finches with different genetic backgrounds were trained on the resulting tune <?>, the training didn't stick. Instead, the greatest predictor of their singing tempo was the way their fathers sang—which they’d never heard. So their genes seemed to be in charge. 但是,這些遺傳背景不同的幼雀,經(jīng)過訓(xùn)練卻無法演唱規(guī)定的“訓(xùn)練曲目”。而是它們父親的鳴叫方式取代了遺傳因素,成為了最能夠預(yù)測它們鳴叫節(jié)奏的手段。而在(梅茨的)實驗中,這些幼雀并沒有聽過其父親是如何鳴叫的。因此,幼雀的基因似乎就是鳴叫方式的主要決定因素。 But then Mets flipped the experiment—exposing genetically similar birds to actual live birds that sang fast, medium, or slow. And that live training appears to have been compelling enough to override the influence of the birds' genetics. So that genetically identical chicks sang tunes fast <> medium <> or slow <>…depending what their tutor sang. 但隨后梅茨又進(jìn)行了一組實驗——讓基因譜相似的幼雀們分別和自然界中的雀類一同生活,這些雀的鳴叫節(jié)奏不同,有快有慢有中速。結(jié)果顯示,生活訓(xùn)練的作用可以有力地覆蓋掉基因?qū)θ给Q方式的影響。因此,這些基因譜相似的幼雀雖然鳴叫的節(jié)奏有快有慢,但都和它們的‘導(dǎo)師’相同。 The results are in the Proceedings of the National Academy of Sciences. [David G. Mets and Michael S. Brainard, Genetic variation interacts with experience to determine interindividual differences in learned song] 本結(jié)果刊于在美國國家科學(xué)院的論文集中。[David G. Mets and Michael S. Brainard, Genetic variation interacts with experience to determine interindividual differences in learned song] The study suggests that the right kind of schooling…or environmental influences… might be able to overcome 'baked in' genetic influence on certain traits. And Mets says this push-pull of nature versus nurture might hold true for humans, too. 研究表明適當(dāng)?shù)慕逃颦h(huán)境也許能夠克服“遺傳信息”對某些性狀的影響。梅茨表示這種先天因素和后天因素之間的相互作用也可能適用于人類。 "We're moving very rapidly into a period where genetic data is easier and easier to collect. And an understanding of these kinds of gene-environment push/pull interactions, and how they impact ultimate phenotypic outcomes, is going to be important in understanding things like cancer susceptibility." Because that too has both genetic and environmental factors. “現(xiàn)如今,基因數(shù)據(jù)的收集變得越來越容易。我們可以了解基因和環(huán)境之間的促進(jìn)/抑制作用,以及它們?nèi)绾斡绊懽罱K表型,這在研究癌癥易感性等方面是很重要的。”因為癌癥的發(fā)生也包括遺傳和環(huán)境因素之間的相互作用。 But no word yet on whether the genetic influences of an off-tempo human father…can be conquered with enough training. 但對于后天足夠的訓(xùn)練是否能夠彌補(bǔ)先天的不足,現(xiàn)在仍然沒有確定的說法。