When Hurricane Irma blew through the Turks and Caicos, lizards with shorter hindlimbs lucked out. Jason G. Goldman reports.?颶風伊瑪吹過特克斯和凱科斯群島時,后肢較短的蜥蜴僥幸脫險。Jason G. Goldman報道。
? 撰文\播音:賈森·G·戈德曼(Jason?G.?Goldman) 翻譯:邱燕寧 審校:郭曉
? At about 7:30 P.M. on September 7, 2017, Hurricane Irma reached the Turks and Caicos Islands. By the next morning, the neighborhood called Blue Hill was gone. And on South Caicos Island, 75 percent of rooftops were obliterated. Two weeks later, Hurricane Maria followed in Irma's destructive footsteps.? 2017年9月7日下午7點30分左右,颶風伊瑪?shù)诌_特克斯和凱科斯群島。到第二天早上,附近的一個叫藍山的地區(qū)已被徹底侵襲。在凱科斯南部島上,75%的屋頂被夷為平地。兩周后,颶風瑪麗亞緊隨伊瑪的破壞性腳步而來。 And Harvard University biologist Colin Donihue happened to be there a few days before the hurricanes blew through. "The Turks and Caicos islands is home to a couple of different endemic species of lizard, that's lizards that are only found there. We were interested in one in particular, called?Anolis scriptus, the Turks and Caicos anole." 哈佛大學生物學家Colin Donihue在颶風爆發(fā)前幾天碰巧在那里。 “特克斯和凱科斯群島是當?shù)?/span>幾種不同的蜥蜴的家園,這些蜥蜴只有在那里才能找到。我們對其中一種特別感興趣,叫做Anolis scriptus,特克斯和凱科斯變色蜥”。 The mission of that first expedition, before the two hurricanes, was to assay the lizard population in anticipation of a program to eradicate the islands of invasive rats—which threaten the lizards. This work included taking detailed measurements of the bodies of lizards they trapped and released.? 在這兩次颶風之前,首次研究考察的任務是檢驗蜥蜴的數(shù)量,以期能制定出一項計劃來消滅威脅蜥蜴的入侵性老鼠。這項工作包括對被捕獲和釋放的蜥蜴的身體進行詳細的測量。 The researchers intended to return several years later, after the rats were gone, to re-assess the lizards. But that plan changed.? 研究人員打算在老鼠被消滅后的幾年之后返回,重新評估蜥蜴。但是這個計劃改變了。 “We realized after the hurricanes had come through that we had a really serendipitous opportunity to test this question of whether hurricanes can act as agents of natural selection on wild populations in their path. Now this had never really been asked before, because hurricanes are just really hard to predict…we just happened to be in the right place at the right time to have that baseline data." “在颶風來襲之后,我們意識到,我們有一個非常偶然的機會來檢驗這個問題,即颶風是否能夠作為自然選擇的媒介,影響其途徑的野生種群。這個問題在以前從未被問及過,因為颶風真的很難預測……我們只是碰巧在正確的時間,在正確的地點獲得了基底數(shù)據(jù)。” Which is why he and his team returned to the archipelago…just six weeks after his first visit. 這就是為什么他和他的團隊在第一次訪問后六周就再次回到群島的原因。 They expected that lizards with longer limbs and larger toe pads would be the ones better able to cling to trees and therefore more likely to survive the storms. And they were?almost?right. Longer front legs and larger toe pads indeed helped. But?shorter?hindlimbs were actually better. The results are in the journal?Nature. [Colin M. Donihue, et al.,?Hurricane-induced selection on the morphology of an island lizard] 他們預計,肢體較長、腳趾墊較大的蜥蜴將能更好地抓住樹木,因此更有可能在暴風雨中存活下來。他們幾乎是對的。較長的前腿和較大的腳趾墊確實有幫助,但是短的后肢實際上更好。研究結果發(fā)表在《自然》雜志上。 To figure out these counterintuitive findings, the researchers conducted an experiment in a hotel room. They rounded up some lizards, gave them a perch, and used a leaf blower to mimic the effects of high winds. They set up a net to catch any lizards that lost their grip.? 為了解釋這些反常的發(fā)現(xiàn),研究人員在旅館房間里做了一個實驗。他們收集了一些蜥蜴,給它們一個棲木,用一個吹樹葉機模擬強風的效果。他們拉起了一個網捕捉那些失去抓力被吹落的蜥蜴。 As the artificial wind blew, the lizards moved so the perch took most of the air flow. But their hind legs would stick out—and if those rear limbs stuck out too far, they acted as sails.? 隨著人工風的吹拂,蜥蜴進行移動,所以棲木承受了大部分氣流。但是它們的后腿會伸出來,如果它們的后肢伸得太遠,后腿就會像帆一樣。 "Eventually those back legs were blown off the perch, and the lizards were just holding on with their front two legs. And they could only hold on like that for so long as the wind speed increased further and further, until they were blown off the perch and into the nets." 最后,那些后腿從棲木上被吹走了,而蜥蜴只是用前腿支撐。他們只能這樣堅持下去,風速越來越大,直到他們被吹離了棲木并落入網中。” So?shorter?back legs gave a survival advantage. A trait that might be passed on to the next lizard generation.? 因此,短的后腿具有生存優(yōu)勢。這個特征可能會傳給下一代蜥蜴。