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The basic process seems straightforward, but its details are extraordinary. [qh]
这一基本的过程似乎很简单，但其细节却非同寻常。[qh]
High-pitched sounds quickly lose energy in air, so bats must scream to make calls that are strong enough to return audible echoes. [qh]
高音调声音在空气中会很快失去能量，所以蝙蝠必须尖叫才能发出足够强的叫声，以传回可听到的回声。[qh]
To avoid deafening themselves, bats contract the muscles in their ears in time with their calls, desensitizing their hearing with every shout and restoring it in time for the echo. [qh]
为了避免耳聋，蝙蝠会在发出叫声时及时收缩耳朵肌肉，每当发出声音时就减弱听觉，接收回声时就恢复听觉。[qh]
Each echo provides a snapshot in time, so bats must update their calls quickly to track fast-moving insects; fortunately, their vocal muscles are the fastest known muscles in any mammal, releasing up to 200 pulses a second. [qh]
每次回声都提供了一个及时的快照，所以蝙蝠必须快速更新它们的叫声来跟踪快速移动的昆虫; 幸运的是，蝙蝠的声带肌肉是已知哺乳动物中变化速度最快的肌肉，每秒可以释放200次脉冲。[qh]
A bat’s nervous system is so sensitive that it can detect differences in echo delay of just one- or two-millionths of a second, which translates to a physical distance of less than a millimeter.[qh]
蝙蝠的神经系统非常灵敏，它可以探测到只有百万分之一秒或百万分之二秒的回声延迟差异，换算成物理距离不到一毫米。[qh]
A bat thus gauges the distance to an insect with far more precision than humans can.[qh]
因此，蝙蝠对昆虫距离的测量比人类精确得多。[qh]
Echolocation’s main weakness is its short range: Some bats can detect small moths from about six to nine yards away. [qh]
回声定位的主要弱点是距离较短:一些蝙蝠可以探测到大约6到9码外的小飞蛾。[qh]
But they can do so in darkness so total that vision simply doesn’t work.[qh]
但蝙蝠在黑暗中也能这样做，以至于视觉根本不起作用。[qh]
Even in pitch-blackness, bats can skirt around branches and pluck minuscule insects from the sky. [qh]
即使在漆黑的环境中，蝙蝠也能绕过树枝，从空中捕捉微小的昆虫。[qh]
Of course, bats are not the only animals that hunt nocturnally. [qh]
当然，蝙蝠并不是唯一一种夜间捕食的动物。[qh]
In the Tetons, as I watch Barber tagging bats, mosquitoes bite me through my shirt, attracted by the smell of the carbon dioxide on my breath. [qh]
在提顿山脉，当我看着巴伯给蝙蝠带追踪器时，蚊子被我呼出的二氧化碳气味吸引，隔着我的衬衣咬了我。[qh]
While I itch, an owl flies overhead, tracking its prey using a radar dish of stiff facial feathers that funnel sound toward its ears. [qh]
当我发痒的时候，一只猫头鹰从我头顶飞过，用一种雷达天线般的硬挺面部羽毛来追踪猎物，而面部羽毛可以把声音汇集到它的耳朵里。[qh]
These creatures have all evolved senses that allow them to thrive in the dark. [qh]
这些生物都进化出了能在黑暗中发挥很好作用的感官。[qh]
But the dark is disappearing.[qh]
但黑暗正在消失。[qh]
Barber is one of a growing number of sensory biologists who fear that humans are polluting the world with too much light, to the detriment of other species. [qh]
越来越多的感官生物学家担心人类使用太多的光污染世界，从而损害其他物种，巴伯就是这些科学家中的一员。[qh]
Even here, in the middle of a national park, light from human technology intrudes upon the darkness. [qh]
即使在这里，在国家公园的中央，人类科技的光线也侵入了黑暗。[qh]
It spews forth from the headlights of passing vehicles, from the fluorescent bulbs of the visitor center, and from the lampposts encircling the parked cars. [qh]
从过往车辆的车灯、游客中心的日光灯到围绕停放汽车的灯柱都发射着光线。[qh]
“The parking lot is lit up like a Walmart because no one thought about the implications for wildlife,” Barber says.[qh]
巴伯说:“这个停车场像沃尔玛一样亮着灯，因为没有人考虑过这对野生动物的影响。”[qh]
Many flying insects are fatally attracted to streetlights, mistaking them for celestial lights and hovering below them until they succumb to exhaustion. [qh]
许多飞虫被路灯深深吸引，误以为是天上的光，在路灯下盘旋，直到精疲力竭死去。[qh]
Some bats exploit their confusion, feasting on the disoriented swarms. [qh]
一些蝙蝠混淆了猎物，以迷失方向的蜂群为食。[qh]
Other, slower-moving species, including the little brown bats that Barber tagged, stay clear of the light, perhaps because it makes them easier prey for owls.[qh]
其他移动速度较慢的物种，包括巴伯放追踪器的棕色小蝙蝠，都远离光线，可能是因为这让它们更容易成为猫头鹰的猎物。[qh]
Lights reshape animal communities, drawing some in and pushing others away, with consequences that are hard to predict.[qh]
灯光重塑了动物群落，吸引了一些动物进来，又赶走了一些动物，其后果难以预测。[qh]
