小譯說
新型冠狀病毒引起的肺炎鬧得人心惶惶，全國上下不得安寧，根據研究表明，病毒的源頭可能是蝙蝠。可真的怪蝙蝠嗎？蝙蝠憑一己之力將病毒封印，晝伏夜出，可還是有人為了貪圖口欲，滿足自己變態的心理，抓住蝙蝠，大吃特吃。我們先來了解一下這些夜晚的小精靈吧。
Bats can be a little scary-looking, but the diverse flying mammals are broadly beneficial to the ecosystems where they — and we — live. Below are 6 facts about these underappreciated creatures.
蝙蝠看起來可能有點嚇人，但這些種類繁多的飛行哺乳動物卻給它們和人類共同生活的生態系統帶來了不少好處。看完下面六個真相，也許你會對這些被低估的小可愛有更多的了解。
Bats account for about 20% of all mammal species.
蝙蝠物種數約佔哺乳動物總物種數的20%。
With more than 1,200 species included in the order Chiroptera, bats represent one of the largest orders of mammals. They are surpassed only by the order Rodentia, which boasts a whopping 2,277 species — 40% of all mammalian species.
翼手目擁有多達1200多個物種，這也讓蝙蝠成為哺乳動物中最大的目之一。唯一超過它們的物種是齧齒動物目，其擁有的物種多達2277種，佔所有哺乳動物物種的40%。
Chiroptera is separated into two suborders: megabats and microbats. Megabats, commonly known as fruit bats or flying foxes, have excellent vision and feast on fruit and nectar. Microbats, like the painted bat of Southest Asia (pictured), are characterized by their use of echolocation and an appetite for insects or blood.
翼手目分為兩個亞目，分別是大蝙蝠亞目和小蝙蝠亞目。大蝙蝠，俗稱果蝠或狐蝠，視力極佳，以水果和花蜜為食。小蝙蝠，包括亞洲最南端的彩蝠（如圖），其特點是可以回聲定位和以昆蟲或血液為食。
Bats are found across the planet.
蝙蝠遍布全球。
As with birds, flight has allowed bats to travel and settle in all corners of the Earth, with the exception of the Arctic and Antarctic. Bats generally roost in caves, crevices, foliage and man-made structures like attics or under bridges.
與鳥類一樣，雙翼使蝙蝠可以在地球上除南北極外的各個角落飛行和安家。蝙蝠通常棲息在洞穴、裂縫、葉叢和人造建築中，比如閣樓或橋下。
At least 45 species of bats are present in the United States alone, with the most common species being the little brown bat, the big brown bat and the Mexican free-tailed bat.
僅在美國棲居的蝙蝠就至少有45種，其中最常見的是小棕蝠、大棕蝠和墨西哥無尾蝙蝠。
Microbats use echolocation to hunt prey.
小蝙蝠利用回聲定位來捕食獵物。
Although microbats are not blind, their true perceptive strength lies in their ability to use echolocation, also known as biosonar.
雖然小蝙蝠不是盲「蝠」，但它們真正感知物體的能力要依賴於回聲定位（也稱為生物聲波）。
Bats aren't the only animals that can use biosonar. Shrews, dolphins and some cave-dwelling birds also use echolocation to navigate their surroundings and hunt for prey.
蝙蝠不是唯一可以使用生物聲波的動物。鼩鼱、海豚和一些穴居鳥類也會利用回聲定位，來辨別方向並尋找獵物。
As bats forage for food, they emit a continuous stream of high-pitched sounds audible only to other bats. When the sound waves collide with a nearby insect or object, the interrupted waves echo back, generating an acute sonic representation of the bat's surroundings. This ability is so sensitive that it can detect objects as thin as a single human hair.
蝙蝠覓食時，會發出連續的高音，但這些聲音只有蝙蝠才能聽到。聲波撞到附近的昆蟲或物體時，會產生回聲，隨即把周圍環境的波形傳回蝙蝠。蝙蝠的回聲定位極其敏感，甚至可以探測到細如髮絲的物體。
Some species are equipped with specific characteristics that allow for more fine-tuned biosonar readings. For example, the Mediterranean horseshoe bat (pictured) is named for its peculiar, horseshoe-shaped nose leaf — a fleshy, complex structure surrounding the nostrils that helps focus sound waves.
有些蝙蝠品種有著特殊的外形，可以接收到更精細的聲波。比如地中海菊頭蝠（如上圖），因其奇特的馬蹄形鼻葉，所以英文名為「馬蹄蝠」。這種馬蹄形鼻葉是一種環繞鼻孔的複雜肉質結構，有助於聚焦聲波。
Likewise, long-eared bats possess prominent ears with geometric inner ridges that sharpen echolocation signals and allow for passive listening of sound produced by prey, such as the fluttering of moth wings.
同樣，長耳蝠有著突出的耳朵，耳朵內脊呈幾何形，可以銳化回聲定位信號，以及針對獵物發出的聲音產生被動聽覺，比如飛蛾翅膀的拍打聲。
Another type of bat, the common big-eared bat, makes use of a natural tool to catch difficult prey — specifically by angling sound waves off a leaf to fine tune the location of motionless prey.
另一種蝙蝠，即普通的大耳蝠，會利用一種自然工具來捕捉不易捕獲的獵物，它們會用樹葉調節聲波角度，從而對獵物的位置進行精準定位。
As Smithsonian aptly describes it, the bats use leaves as "acoustic mirrors," a habit discovered by Inga Geipel, a scientist at the Smithsonian Tropical Research Institute (STRI) in Panama, and a team of scientists there.
史密森學會（Smithsonian）的描述很恰當：蝙蝠把樹葉當成了「聲反射鏡」，巴拿馬史密森熱帶研究所（Smithsonian Tropical Research Institute）科學家英加·蓋佩爾（Inga Geipel）和那裡的一個科學團隊發現了蝙蝠的這種習性。
Besides just being interesting, this knowledge also rules out a common belief: that the one way to defy echolocation is to remain motionless and silent. For the dragonflies in this experiment, that turned out not to be the case.
這一發現不僅十分有趣，同時也澄清了此前一個普遍觀點：躲避回聲定位的唯一方法就是保持不動和保持安靜。對於試驗中的蜻蜓來說，事實並非如此。
Bats 'waggle' their heads to hear better.
蝙蝠「搖頭晃腦」，是為了聽得更清楚。
You know how a dog cocks its head as if to better understand what a human is saying? Well, bats do the same thing, only they do it while flying. Their motion is similar to what dogs, cats and even humans do, but bats do it for a different reason: to fine tune the location of prey as they're echolocating.
大家都知道狗狗們有時會抬起頭，好像是為了更好地理解主人在說什麼。事實上，蝙蝠也會做同樣的事情，只不過它們只有在飛行時才會如此。蝙蝠的這個動作與狗、貓甚至人類的動作都很相似，但不同的是，它們這樣做的目的，是在回聲定位時對獵物的位置進行微調。
The Christian Science Monitor — which artfully compares the motion to a tiny flying puppy — explains the research of Melville Wohlgemuth of Johns Hopkins University. Wohlgemuth, a neuroscientist whose specialty is echolocation, sums it up relatively simply. The bat has to sort out the clutter, and turning its head allows it to do that.
《基督教科學箴言報》（Christian Science Monitor）巧妙地將這一運動比作一隻會飛的小狗，這個比喻出自約翰斯霍普金斯大學（Johns Hopkins University）的梅爾維爾沃爾格茅斯（Melville Wohlgemuth）的研究。沃爾格茅斯是一位神經科學家，對回聲定位有著專門研究。根據他相對簡單的總結，蝙蝠必須「理清頭緒」，而轉動頭部就可以做到這一點。
Female bats can control when they get pregnant and give birth.
雌蝙蝠可以控制懷孕和分娩的時間。
To ensure external conditions are optimal for a newborn bat, mother bats are equipped with a variety of biological tactics that allow them to put off fertilization, implantation or development of the fetus.
為了給蝙蝠寶寶創造最佳的外部條件，蝙蝠媽媽掌握著多種生理策略，可以推遲受精、胚胎著床以及胎兒發育。
In some species, mating will occur in the fall, but females will store sperm in their reproductive tract before finally fertilizing their eggs when spring arrives. In other species, the egg is fertilized immediately after mating, but instead of implanting to the wall of the uterus, it floats around until favorable conditions arrive.
有些蝙蝠的交配時間在秋季，但雌性蝙蝠會在春天到來、卵子完成最終的受精之前，先把精子儲存在生殖道中。而對於其他一些物種，交配過後卵子會立即受精，但受精卵並不會在子宮壁著床，而是漂浮在周圍，直到外部環境變得對生育有利。
Yet another adaptation exhibited in some bats is delayed fetus development, in which fertilization and implantation occurs as usual, but the fetus remains in a dormant state for a long period of time.
此外，某些蝙蝠還可以延遲胚胎發育，在這種情況下，受精和著床照常，但胚胎長期處於休眠狀態，這也是蝙蝠適應外界環境的一種表現。
These tactics, which contribute to the slow birth rate of bats, are timed to coincide with high production of fruit or insects in the environment.
這些生理策略會降低蝙蝠的出生率，但如此一來，幼兒蝙蝠出生之時恰好是周圍水果產量、昆蟲數量豐富的時候。
Bats hang upside-down to conserve energy.
蝙蝠倒掛是為了節省能量。
If humans hung upside-down from a tree for several hours, it wouldn't take long before they passed out. So how do bats manage it?
人類如果倒掛在樹上幾個小時，很快就會昏倒。那蝙蝠是怎樣做到的呢？
For starters, human and bat circulatory systems are fundamentally different. Because our blood pumps in the direction of our brain, the stress of gravity transfers even more blood to the head when upside-down. A bat's circulatory systems pumps the opposite way — away from its head.
首先，人類和蝙蝠的循環系統完全不同。因為我們的血液向大腦的方向泵送，上下顛倒後，重力會將更多的血液輸送到頭部。而蝙蝠的循環系統剛好相反，它把頭部血液輸送到全身。
Also, while all mammals have valves in their veins that prevent blood from flowing backward, bats possess these valves in their arteries, as well. All of these adaptations ensure blood is evenly distributed throughout the bat's body.
此外，雖然所有哺乳動物的靜脈中都有防止血液倒流的瓣膜，而在蝙蝠的動脈中也有這種瓣膜。這些特徵可以確保血液均勻地分布在蝙蝠的全身。
It also just happens to be more energy-efficient for bats to hang by their feet. As opposed to defying gravity and standing upright, no energy has to be expended while hanging due to the lightweight structure of their leg muscles and bones that were developed for flight.
蝙蝠用腳倒掛起來時，碰巧會節約更多的能量。蝙蝠為了飛行進化出了輕巧的腿部肌肉和骨骼，所以，與對抗重力和直立站立不同，它們在懸掛時不需要消耗任何能量。
蝙蝠是地球生態鏈中不可缺失的一環，為大自然的生態平衡貢獻著不可磨滅的力量。罪魁禍首不是蝙蝠，不是蛇，不是野生動物，是醜陋變態的心理，是惡臭愚昧的嘴臉。拒絕野味，從我做起。
本文為百度翻譯原創內容
翻譯：郝澤坤 （北語）
編輯：Patricia
文章來源：Mnn