拥有随心所欲穿越天空的能力 The ability to move through the air in any direction you wish,
得以横跨大陆与海洋 to cross continents and oceans,
越过森林，沙漠和高山 to range over forests and deserts and mountains,
鸟类能做到这些已经有1亿5千万年了 all this birds have been able to do for 150 millions years.
但它们不是最先或最后飞上天空的生物 But they won't the first or indeed the last in the skies.
我们要出发探索自然界最令人赞叹的故事 We are setting out to explore one of the most astonishing stories in the natural world.
了解动物如何从地面跃升而起 The way in which animals manages to rise up from the surface of the Earth,
占据空中领地 and colonise the air.
从令人眼花缭乱的昆虫飞行特技 From the dazzling aerobatics of the insects...
到体形庞大的古老有翅爬虫类 to the majesty of ancient winged reptiles.
华丽与灵巧兼具的鸟类 The splendor and agility of birds...
以声纳精准导航的夜行蝙蝠 and the sonar guided precision of night flying bats.
飞行能力是某些 Flight has been the key to the success
最卓越的地球生物的成功关键 of some of our Planet most remarkable inhabitants.
为了分析它们的精湛技巧，我们将使用最新科技 To analyze theirs spectacular skills, we will use the latest technology.
并走遍全世界 And we will travel around the world.
从婆罗洲丛林到藏有丰富化石的中国岩层 From the jungles of Borneo to the fossils filled rocks of China.
以及厄瓜多尔森林的云雾林 And the Cloud Forest of Ecuador.
我们将带你登上天空 We will take you into the air...
跟着动物一起飞行前进 and travel with animals as they fly.
征服天空 ~ Conquest Of The Skies ~
飞行始祖 THE FIRST TO FLY
这个惊人故事起点的证据 Evidence for the very beginning of this astonishing story
在自家的剑桥沼泽里就能找到 could be found coast to home in The Fens of Cambridgeshire.
这里生物的祖先可回溯至数百万年前 Here live creatures that have ancestry stretching back millions of years.
没人能确认世上第一个飞行动物是怎么演化而成的 never we know exactly how the first flying animals in the world evolve,
但现在有些生物能带我们回到 but there are creatures alive today, that can take us back
那个遥远的神奇年代 to those far distance remarkable times,
让人意外的是，它们生活在水里 and they live surprisingly under water.
穿越水面看着下方的河床 Looking down through the surface to the riverbed,
就像回到三亿两千多万年前的过去 is like traveling back in time over 320 million years.
那个远早于恐龙出现的年代 It was then, in an age long before even the dinosaurs evolved,
像这样的生物首次出现在地球的水域 that creatures like this first appeared in the waters of the Earth.
这是一种昆虫 It's an insect.
这种凶恶掠食动物的下颚有如挖土机抓斗 A ferocious predator with jaws like a mechanical grab.
虽看似不可能的这种动物祖先 It seems unlikely that this animal ancestors
却是最早能飞行的生物之一 were among the first creatures ever to fly.
但这只昆虫还没成年，它是幼虫 But this one is not yet adult, it's a larva,
且它不会在水里度过一生 and it doesn't spend all his life in the water.
它在水面上有另一种生活和另一副身体 It has another life and another body above the surface.
某天清晨，它爬上一根芦苇 Early one morning it climbs up a reed.
它的表皮出现一条裂缝，一个长相完全不同的生物开始冒出来 A split appears in its skin, and a very different looking creature begins to emerge.
它的背部有四处隆起，那或许是因为 It has four lumps on its back, that might perhaps ancestry
它的祖先有鳃或是保护性硬壳 have become either gills or protective armor plates.
但现在它们演变成很不一样的东西 But now they develop into something very different.
翅膀 Wings.
它们有两对翅膀 It has two pairs of them.
它的体液沿着翅脉流入把翅膀撑开 Liquid from its body is pumped out along veins to stretch them tight.
等到被太阳晒干后，翅膀就变硬 As they dry in the sun, they harden.
这只水趸已经变成蜻蜓 The watering dragon has become the Dragonfly.
它用来飞行的四片翅膀 And the four wing depurates that he uses to get into the air,
是我们所知最古老的飞行器官 is the earliest that we know.
在古老湖泊和溪流的底部 Imprints of such wings, have been found in rocks that was lay-down
都曾找到这种翅膀的化石 on the bottom of ancient lakes and streams.
这个化石有一亿五千万年历史 This specimen is about 150 million years old.
而这个翅膀则是化石两倍，有近三亿年历史 And this wing is double age at nearly 300 million years old.
古代和现代的翅膀都有极其相似的结构 Ancient and modern wings share a structure that is strikingly similar.
所以现在的蜻蜓是惊人的活化石，让我们看见最早的飞行生物 So today's Dragonflies are amazingly living fossils that can show us
如何克服重力，在空中翱翔 how the very first flyers overcame the pull of gravity, and took to the skies.
它们的翅膀是大自然的工程奇迹 Their wings are marvels of natural engineering.
但要知道这些翅膀怎么让蜻蜓升空 But to see how they lift the Dragonfly into the air,
需用慢动作画面检视 we need to slow the action down.
基本上，这看起来很简单，将每片翅膀往下拍 In principle, it looks very simple, each wing beats-down,
挤压下方的空气，这样就能把蜻蜓往上抬 pushing on the air below, so lifting the Dragonfly up.
但每次拍翅也会制造另一道气流 But each beat also creates another air current
透过不同的方式让蜻蜓升空 that lifts the Dragonfly in a very different way.
我要用这片纸条代翅膀做示范 And I can demonstrate it, using this strip of paper to represent a wing.
如果我在上方吹气，纸条就会抬起来 瞧 If I blow across the top of it, it will rise. Watch.
那是因为空气流速越快，气压越低 That is because the faster air moves, the lower its pressure.
我在翅膀上方制造低压 So I created a lower pressure above the wing,
因此翅膀就被往上吸 and in consequence it was sucked upwards.
飞行物的问题，就是要重现这种空气流速的落差 The problem for a flying animal, is to recreate that difference in air speed.
蜻蜓以令人赞叹的方式做到这点 The way the Dragonfly does this is remarkable.
当蜻蜓在空中飞行，可以看到它把翅膀扭转成不同角度 As it moves through the air, we can see that it twists its wings at different angels.
用力拍时，它把翅膀摆成稍微往上的角度迎向气流 On the powerful down-beat, it holds them at a slight upward angle to the air flow,
这能在翅膀上方产生一种神奇的效果 and this produces an extraordinary effect above the wing.
能在翅膀前缘后方制造出气流，让空气旋转 It create a swirl behind the leading edge, which spins the air round,
加快通过翅膀上方的气流速度 increasing the speed of the air current over the top of the wing.
气流速度只要稍微加快，就能制造巨大的向上力 And with just a tiny increasing speed generates a significant upward force.
把翅膀和蜻蜓抬高 Lifting up the wing and the Dragonfly.
接着蜻蜓就能改变拍翅的方向 The Dragonfly can then change the direction of its wing beats
把自己往前和往上推进 to propel it forwards as well as upwards.
惊人的是，蜻蜓可以分别拍动四片翅膀 Remarkably, a Dragonfly can beat each of its four wings independently.
这能让它做出变化多端的飞行动作 And that enable it to perform an astonishing variety of maneuvers.
可以悬停 It can hover.
可以滑翔 It can glide.
甚至可以倒退飞行 It can even fly backwards.
使出最大力度同时拍动两对翅膀 For maximum power, it beats both pairs together,
可以急转弯 and can make really sharp turns.
蜻蜓的始祖 So the very first Dragonflies were able
因此能够把领地拓展到四面八方 to extend their territories far and wide.
在空中随着越来越多昆虫加入进来 And as more insects joined them in the skies,
蜻蜓也有成为致命空中猎人的技能 the Dragonflies had the skills to be deadly aerial hunters.
飞行能力让远古昆虫取得极大优势 The ability to fly brought great advances to those early insects.
这能帮助它们觅食和躲避掠食动物 It enable them to find food, to escape from predators,
还有重点，就是得以前往新领域寻找配偶 and particularly important, to travel to new territories in search of a mate.
豆娘跟它们的近亲蜻蜓一样 Damselflies like their close relations Dragonflies,
数百万年来几乎未曾改变 have remained virtually unchanged for millions of years.
如果配对双方都会飞，要进行交配会有点复杂 Mating can be quite complicated when both partners can fly,
豆娘就是必须解决这个问题的飞行动物始祖之一 and these were among the first kind of animals that had to deal with that problem.
这只豆娘的蓝色身体显示它是雄性 The blue color of this one shows that it's a male.
为了吸引异性，公豆娘必须奉上一份大礼---一块领地 To attract a female, a male must have something to offer her---A territory.
它选择有足够食物喂饱幼虫的水域 He chooses a stretch of water, that is likely to contain plenty of food for his offspring.
然后捍卫这片领地不让对手抢走 Then he guard this territory against any rivals.
直到有母豆娘飞过来加入它 Until a female flies in and joins him.
它现在必须抓住母豆娘以免它改变心意，必要时就在半空中进行 He must now grab her before she changes her mind, in mid air if necessary.
它用腹部尾端的交尾器抓住母豆娘颈部后方 He uses Claspers at the tip of his abdomen to grip her behind her neck.
惊人的是，这对配偶的八片翅膀竟然能同步拍动 Amazingly, the pair are able to coordinate the beats of their eight wings.
它们可能在空中交配，或是选择能避开掠食动物的僻静栖木 They may mate in the air, or choose a secluded patch where they be safe from predators.
然后它们会在领地飞行绕圈，产下授精卵 They then fly around the territory, laying their fertilized eggs.
飞行让昆虫得以进入 Flight enable insects to invade part of the Planet
先前不曾有生物居住的区域---空中 that until then had been uninhabited. The air.
它们开始兴盛繁衍 And they flourished.
在三亿两千万年前空中挤满飞行昆虫 So, 320 million years ago the skies flaunt with flying insects.
但这些最早的四片翅膀生物 But those early four wing forms were destined to produce
将会繁衍出各种高度特化的飞行后代 a all range of spectacular highly specialize flyers.
在水里产卵的需求，让蜻蜓始祖 The need to lay eggs in water, tied the first Dragonflies
只能在像这样的溪流与水池生活 to streams and ponds like these.
但它们出现之后约两千万年 But then around 20 million years after their arrival,
不需要依靠水的新形态飞行昆虫开始现身 a new kind of flying insect appeared with no such ties to water.
它们成功的证据几乎无处不在 Proof of their success can be found almost wherever you look
但证据最充足之处莫过于婆罗洲 and few places more abundantly then in Borneo.
飞行始祖有两对翅膀 The very first flyers had two pairs of wings,
现在我们要去寻找它们的继任者 now we looking for their successors.
有一群生物 One group of creatures adapted that original
继承四片翅膀的原始设计而大为成功 four wing design with such success,
进而分化成世上数量最多 that they diversified into the most numerous
分布最广的动物种群 and wide spectrum of animals on the entire Planet,
在下方的雨林可以找到其中最壮观的范例 and you can find some of the most spectacular examples down there in the rainforest.
并非所有昆虫都是掠食动物，有些跟这种一样是纯素食者 Not all insects are hunters, some are strict vegetarians like this one.
这是在水下生活的陆地版本 This it is the land living equivalent to that underwater monster,
巨大蜻蜓幼虫 the Dragonfly larva.
但这种幼虫不是抓小鱼或水蚤来吃，而是啃食木屑 But this larva instead of catching little fish and water fleas, munches wood pulp.
问题是木屑没什么营养 The trouble is that wood pulp is not very nutritious,
这种生物必须至少吃一年木屑 and this creature, has to eat it for at least a year,
才能达到这种成熟体形的大小 before is this size, which is full grown.
接着这只幼虫就会变成同样巨大的成虫 But then this larva will turn into an adult, which is equally monstrous.
从幼虫生活和进食的地底冒出来的 Emerging from beneath the ground, where it is lived and fed as a larva, is a beetle.
是世上最大的甲虫之一---南洋大鼎虫 One of the biggest in the world---The Atlas Beetle.
跟这只一样的公虫有长触角 Males like this one are armed with long horns,
这是用来跟觅偶对手竞争的强力武器 powerful weapons with which to compete with rivals for a mate.
它现在多数时间都待在地面上 It now spend most of his time above the ground,
横行穿越灌木丛，在这里吸树液和啃食掉落的水果 margined its way through the undergrowth, where it feed on tree-sap and fallen fruit.
这种体形庞大的强壮生物虽然看起来不像会飞 This hefty powerful creature may not look as if it could fly.
但它能 But it can.
在生命中的关键时刻它会飞上天空 At key moments in its life he takes to the air
寻找新的食物来源，当然还有寻觅异性伴侣 to look for new sources of food, and of course, a female.
到处钻爬翻找可能会伤害脆弱的翅膀 Alls burrowing and munching around could injure delicate flight wings,
所以甲虫的前翅 so beetles have harden the front pair
已硬化成保护性的外壳 to form this pair of protective covers,
娇弱的飞行用翅膀安全地藏放在下方 and the delicate flight pair are stored away in safety underneath.
要知道翅膀怎么折放在硬壳里，得等它飞起 To see how the wings are folded away beneath their covers, we need to wait for take-off.
它拍翅时，铰链关节会弹开，翅膀张开到完整尺寸 As it flaps, sprung hinges click-open and the wings are stretch to their full size.
它的飞行翅膀制造升力的方式跟蜻蜓一样 The working wings create lift in just the same way that the Dragonfly wings do,
已经变成硬壳的前翅，则往两边张开 and the front wings, protecting them as a covers, are held out to the side.
它们的形状也能提供一点额外的升力 And their shape does give a little extra lift.
但这只甲虫显然是蹩脚的飞行员 So it clear that this is a really are all clumsy flyer.
它的降落技术也不太好 Landings can be clumsy too.
现在那对脆弱的翅膀必须小心收回硬壳里 And now those fragile wings must be carefully packed away beneath of their covers.
这要透过腹部底部的一排细毛导引 They guided by align of tiny hairs of the base of the abdomen.
这些细毛会卡住翅膀，协助把它们推送到位 These grip the wings and help push them into position.
甲虫收翅小心谨慎的程度 The beetle does it with all the care and precision
就跟跳伞员收好降落伞一样 that a skydiver uses when packing away his parachute.
一旦抵达新领地，它就去抢占新的食物资源 Once in a new territory, it will stake out a fresh source of food,
并且努力捍卫，等候母甲虫抵达 and then defend it until a female arrives.
结果证实甲虫的生活方式极为成功 The beetle way of life proved astonishingly successful.
目前发现的甲虫种类超过37万种 There are over 370,000 different species of beetle so far discovered.
这个数据非常惊人 Unbelievable figure.
甲虫从远古开始就成功地只用一对翅膀 So early on, the beetles manage to fly as much as they need to,
飞到它们要去的地方 with just one pair of wings.
接着约在5700万年前 And then around 57 million years ago,
在飞行史上又出现另一次关键发展 came another key development in the history of flight.
一种新昆虫出现了 A new type of insect appeared
它们的两对翅膀变成了一大片广告看板 with two pairs of wings that became in effect huge billboards.
这些或许是最令人炫目神迷的翅膀 Wings that are perhaps the most dazzlingly beautiful of all.
蝴蝶 Butterflies.
为了创造这些非比寻常的翅膀，蝴蝶演化出复杂的生命周期 To create these extraorinary wings the butterflies evolved complex life cycle.
它们卵孵化时是有腿的小蠕虫---毛毛虫 They hatch some eggs, as little worms with legs---Caterpillars.
但不同于许多甲虫幼虫，毛毛虫是在易受掠食动物攻击的地面上方觅食 But unlike many beetle grubs, caterpillars find their food above ground where they are very vulnerable to predators.
所以它们演化出几个策略 So they have evolved several strategies
用来累积变成飞行成虫所需的所有身体质量 to accumulate all the bodymass they will need to become flying adults.
首先是尽可能和尽快地大吃 First is to eat as much as they can as quicly as they can.
许多毛毛虫在短短几周内就能达到成熟体形 Many are able to reach full size in just a matter of weeks.
当然，有如小香肠般皮薄肉多的毛毛虫 Of course, little thin skin fat filled sausage
是让鸟类或爬虫类垂涎三尺的小零食 is attempting morsel for any bird or reptile.
所以毛毛虫必须找到方法自卫 So caterpillas have to have a ways to defending themselves.
这只是凤蝶的毛毛虫 This one, which is the caterpillar of lovliest swallowtail butterfly
它把自己伪装成鸟粪 has disguise itself as a bird dropping.
如果这样还骗不过真有鸟想来吃它 If that does not deceive of bird and bird goes for it,
它还有另一种自卫武器 it has another form of defense
它也会散发出难闻的臭味 It's emited rather unpleasant smell as well.
为了努力求生，直到变成有翅膀的成虫 In the struggle to survive long enough they become winged adults,
其他毛毛虫也发展出同样巧妙的自卫方式 other caterpillars have developed other equally ingenious forms of defense.
藏在这些蓬松体毛里的会蜇人的短刺 Consealed with in these fluffy strands are short stinging spikes.
这只毛毛虫有很长的棘毛，里面还有能刺痛人的尖刺 And this one is armed with long spines which have really painful stings
不只这样，它还有作为警告的鲜艳颜色 Not only that, it has this warning colours
告知任何可能的掠食动物，要是胆敢进攻会有麻烦 to tell any potential predator that they will be in trouble if they attack.
这只毛毛虫虽然看似危险，但其实是唬人 This caterpillar my appear to be dangerous, but it is in fact and fraud.
那些棘毛根本不会刺痛人 The spines don't sting at all.
它靠这种伪装让潜在的掠食动物出于忌惮 It's relying on its disquise to make a potential predator think twice
而不碰它 and leave it alone.
不然，干脆躲起来 Or, you can simply hide.
这一些小帐篷是弄蝶的毛毛虫盖的 These little tents have been made by the caterpillars of a skipper butterfly.
每只毛毛虫都先在树叶的边缘咬出圆形的切口 Each caterpillars started by making a circular cut in the edge of the leaf,
但它们会留下一小部分不咬断，用来当作铰链 but it's left one segment uncut. So them act as a hinge.
然后抬起整片碎叶盖住自己 Then it pulls over the whole segment
藏在下面啃食树叶组织 and hides beneath the munch way of the tissues of the leaf.
如果把碎叶拉开，毛毛虫就在里面 And if I just pull it up, there are caterpillars.
在这个危险阶段存活下来的毛毛虫 Caterpillars that survive these hazardious stages,
现在可以准备长出翅膀变成成虫 can now build their wings and turn in to adults.
它们要经历一场彻头彻尾的大转变 They undergo truly radical transformation.
不像蜻蜓是褪去最后一层表皮 Instead of shading of final larvae skin as the dragonfly does,
毛毛虫是先用保护性外壳包住自己 a caterpillar first surrounding itself with a protective shell.
这就像是更衣室 To act as a sort of changing room.
它在里面分解和全面重建自己的身体 Within which it dismantles and then completely reconstructs it's body.
经过差不多10天，它变成蝴蝶 After around 10 days it emerges as a butterfly.
现在体液沿着翅脉流入翅膀撑开成完整尺寸 Now fluid pumps along veins and wings to stretch them out to the full size.
然后它就准备好飞翔了 And then it is ready to fly.
蝴蝶靠采集吸食花蜜维生 Butterflies live on nectar which they collect from flowers.
跟蜻蜓和甲虫一样，它们也要飞行寻找配偶 Like Dragonflies and Beetles they also fly to find a mate.
但它们拍动多彩翅膀的方式则是大为不同 But the way they beat their colorful wings is significantly different.
这种漂亮的生物有两对翅膀 This lovely creature has two pairs of wings,
但这些翅膀已经合而为一了 but he has in effect turn them into one.
方法很简单，就是让较大的前翅叠上较小的后翅 It done that quite simply, by overlapping the larger front pair over the smaller hind pair,
所以拍下前翅时，就能自动带动下方的后翅 so when the front pair beat-down, they automatically press down lower pair.
下方的后翅本身没有能拍翅的肌肉 The lower pair themselves don't have the muscles to beat-down,
但有足够的力道重新抬起翅膀 but just enough strength to return up.
交叠的翅膀比蝴蝶的体形巨大许多 A Butterfly's overlapping wings compare to the size of their bodies, are enormous,
也比其它昆虫的翅膀大了约10倍 around 10 times the size of other insect wings.
因为翅膀较大，每次拍翅膀都能产生强大升力 Because the wing is larger, each beat can generate a huge amount of lift.
为了持续飞行，蝴蝶的拍翅次数比其他昆虫少很多 So to stay in airborne, a butterfly need to flap less often than other insects.
这种慢慢的拍翅动作，也能让它无预警地迅速改变方向 But that slow wing-beat, also enable it to make rapid and unpredictable changes of direction.
所以蝴蝶能以曲折的不规则路线飞行 And that allow Butterflies to fly in that zigzag erratic way,
因此蝴蝶收藏家很难抓到蝴蝶 which make them so difficulty to catch, if you are butterfly collector,
重点是也能让掠食动物感到棘手 or more importantly, a predator.
前后翅交叠的蝴蝶翅膀 The combined front and hind wings of butterfly, not only constitute
不只成就一种高效的飞行机制 也能够传递信息 very effective flying mechanism, they can also carry messages.
实际上，这带有整个动物王国最亮眼的公告讯息 In fact, they carry some of the loveliest advertisements in all of the Animal Kingdom.
例如这只美丽的婆罗洲珠光凤蝶 Like for example, this beautiful Golden Birdwing Butterfly from Borneo.
蝴蝶的巨大翅膀有如大幅画布 The butterfly huge wings provide auspicious canvas
可以展示设计精美的图案 on which they display fantastically elaborate designs.
这些飞行广告是怎么制作出来的？ So, how are these flying advertisements created?
秘密藏在翅膀表面的细微结构里 The secret lies in the microscopic structure of the wing surface.
这些重叠鳞片的排列方式有如屋顶瓦片 These oval lapping scales lined up like tiles on a roof,
这是从原本细小感应器的硬毛演化而成 have evolved from bristles that were once tiny sensors.
有些鳞片含有微小的色素囊袋让翅膀呈现出颜色 Some contain tiny package of pigment that give the wings color.
有些则是具有能折射光线的复杂结构 Others have a complex structure which split the light,
所以从特定角度就能看见，鳞片反射出的鲜艳彩虹 so that when viewed from a particular angle, it reflects a brilliant iridescence.
全球共有超过1万8千种蝴蝶 There are over 18,000 species of butterfly around the world,
每种蝴蝶的翅膀都有专属独特设计 and each has wings with their own distinctive design.
这些亮丽色彩和美丽图案，当然 These ravishing colors and delectable patterns, of course,
能让公蝶和母蝶分辨对方 enable a male butterfly and a female butterfly to know
是否属于同样品种 whether or not they belong to the same species.
准备交配的成年蝴蝶 And a mature adult ready to mate,
可以从惊人的远距离辨识出合适配偶 can identify suitable partner from surprising distances.
当公蝶和母蝶相遇，就会绕着彼此飞动跳起求偶舞 When a male and female eventually meet, they flutter around each other in a ritual dance.
双方都在互相检验飞行技巧和翅膀图案 Each is checking out the flying skills and wingspans of the other.
如果通过彼此的考验，它们就开始交配 If both past the test, they mate.
由于翅膀尺寸庞大，蝴蝶的飞行动作看似缓慢 The sheer size of butterfly wings, might seem to condemn their owners to a slow,
甚至有点迟缓 almost dawdling flight.
但它们其实是出乎你意料之外的高效率飞行员 But they can be much more efficient aeronauts then you might suppose.
蝴蝶不只能飞得很远，令人惊奇的是 Butterflies may not be able to fly very fast, but astonishingly,
这种看似娇贵的生物，可以飞行数百英里觅食 for such frail looking creatures, they can travel for hundreds of miles in search of food.
新发现揭露蝴蝶会长途跋涉 New discoveries are revealing that butterflies make immense journeys,
其中最令人兴奋的研究之一 and one of the most exciting of this studies
是在婆罗洲西方7千英里外的欧洲进行 is taking place 7,000 miles west of Borneo, in Europe.
我要加入西班牙中部的一项研究计划 I am joining a research project in Central Spain,
见识所有蝴蝶旅行者当中最了不起的一群 to look for one of the greaters of all butterfly travelers.
小红蛱蝶 The Painted Lady.
每年春天，西班牙都会出现大量小红蛱蝶 Every spring, Painted Ladies appear in Spain in great numbers.
但西班牙只是中继站 But Spain is just a stopover.
一支国际科学家小组发现的证据 An international team of scientists are uncovering evidence
指出一趟横跨欧洲和更远地区的惊人旅程 of an astonishing journey right across Europe and beyond.
这项极具野心的计划是由康斯坦剃博士提出 This hugely ambitious project is the brainchild of Dr. Constantise Iovanescu.
记录小红蛱蝶在何时和哪里出现的精细资料 Detailed records of when and where Painted Ladies appear
揭露一场不可思议的大迁移 have revealed an extraordinary mass migration.
我们核对了来自 We were able to collect a huge number of observations
60多个国家的大量观察资料 from a more then 60 different countries,
以及约3万5千份记录 真的？ and maybe 35,000 records... - Really?
因为我们有许多人提供观察的记录 in many people contributing their observations,
这是我们第一次得以了解 and for the first time it was possible to understand
全年度迁徙的大致模式 the general pattern of migration all around.
透过集合这批丰富资料 By combining this wealth of data the team are revealing a route map
团队绘制出跨越惊人距离的路线图 that spans incredibly distances.
起点是在北非 And it begins in North Africa.
冬季有大量小红蛱蝶在摩洛哥繁殖 Large numbers of Painted Ladies breed in Morocco over the winter,
然后它们就出发飞跃地中海到欧洲 before setting out across the Mediterranean to Europe.
再随着春天花季北上 They then follow the spring bloom north,
它们和幼虫一路循着长出嫩叶和花朵的植物进食 as the plants that they and their young feed on, sprout leafs and flowers.
夏季，它们出现在英国和斯堪的纳维亚 In summer, they appear in Britain and Scandinavia.
但单一蝴蝶的寿命太短无法独自达成这趟漫长旅程 But no individual butterfly lives long enough to achieve this huge journey by itself.
这趟旅程的每一步都是分别由新生代达成 Each step is taking by a new generation.
所以抵达英国的小红蛱蝶 So, this Painted Lady in Britain
其实是从摩洛哥出发的蝴蝶的孙辈 is the grandchild of a butterfly that set out from Morocco.
但接着到了秋天，所有小红蛱蝶就消失无踪 But then, in autumn, all the Painted Ladies vanish.
是因为它们全体死亡还是这趟史诗级迁移可 能有回程路线？ Do they simply die out? Or could that be a return leg to their epic migration?
为了解答这个谜团 Searching for an answer to this mystery,
令这项计划获得至今最惊人的发现 has given the project its most astonishing revelation yet.
这是来自驻扎伦敦市郊 And it comes from a part of the team based at
罗森斯德研究所的小组成员 Rothamsted Research Institute just outside London.
这个关键发现来自一个意外的源头---雷达 The key discovery emerge from a surprising source---Radar.
我们的雷达有一道垂直波束，这会在上方空中投射 一道狭长光束 Our radar has a vertical pointing beam, and it illuminates a narrow column of the sky above,
就像拿强力手电筒照天空一样 like shining a powerful spotlight up at in the sky,
所以能够侦测到飞跃那道波束的个别昆虫 and we are able to detect individual insects as they fly through that beam.
这个雷达讯号非常精细 甚至能协助辨别品种 The signal is so detailed it can even help identify the species.
在秋季失踪期 And during the autumn disappearance,
雷达发现大量小红蛱蝶 the radar picked up large numbers of Painted Ladies.
它们不是全数死亡 而是在移动中 They won't dying out, they were on the move,
而且是在惊人的高度飞行 and they were flying at astonishing heights.
我们发现在高空有大量的小红蛱蝶 What we find was, that in fact the Painted Ladies were highly abounded,
就在高度300到500公尺处 at heights of three, four, five hundreds meter above the ground.
在这种高空，地面的观察者看不见它们 At this great height, they were invisible to observers down below.
这能解释它们为何消失无踪 This explained their disappearance.
但小红蛱蝶自有绝佳理由要在这种高度飞行 But the Butterflies had their own very good reason to travel at such altitudes.
在300到400公尺高度飞行的好处 One of the benefits of flying at three or four hundreds meter above the ground,
就是风速比地面快很多 is that the wind speed-air much faster than the air ground level,
所以乘风前进能让蝴蝶获益良多 so the insects are able to get a lot of assistance from the wind,
比用自己的力量拍翅飞行快很多 and travel much faster then they would in their own powered flight,
我们看到小红蛱蝶的速度 可以达到时速50甚至70公里 and we see these Painted Ladies traveling at 50 or even 70 km an hour.
不只测量这些蝴蝶的飞行速度 As well as measuring the phenomenal speed of their flight,
雷达也揭露了它们飞行方向 the radar also revealed its direction.
它们正在南下 They were heading south.
所以它们要去哪里 So where will they go?
这个出人意表的答案来自康斯坦剃 分布广阔的观察员网络 The astonishing answer came from Constantise far-flung network of observers,
最关键的资料是在非洲收集到的 and the crucial piece of data was gathered in Africa.
在10月和11月间远征非洲的研究显示 Some expiration in Africa, in October, November,
当时有大量的蝴蝶抵达当地 －－真的？ have shown that there is a huge arrival of Butterflies at that moment. - Really?
到了夏末，欧洲的新生蝴蝶 So, by the end of the summer, the newborn Butterflies in Europe
就开始迁移回到非洲 are start to migrate a little way back to Africa.
真的？---对 Really? - Ya.
在高空乘风飞行的最后一代小红蛱蝶 A final generation riding on high altitude winds makes an immense journey
展开总长3千英里的漫长旅程回到西非 全程仅需要几天时间 of up to 3,000 miles to West Africa, in just a matter of days.
地面的观察员和空中的雷达 Observers on the ground, and radar in the air,
已经发现这个神奇迁移周期的证据 had found proof of an amazing migration cycle.
它们在一年内完成整个的周期 Just in one year the all cycle is made,
总共6代的小红蛱蝶 It is the succession of these 6 generations moving about
拉力飞跃约5千公里， 是来回约各5千公里 5,000 kilometer in one direction, and 5,000 in another direction.
这是至今在全球发现 This migration, is in fact the longest made by
距离最长的昆虫迁徙 any insect on the Planet so far discovered.
但这引发了另一个问题 But that raised another question.
每一代的蝴蝶怎么知道要飞往哪方？ How did each generation know which direction in which to fly?
罗森斯德的科学家再次着手寻找答案 The rothamsted scientists once again set out to find an answer.
方法是追踪比较靠近地面的小红蛱蝶的行为 By tracking the behaviour of Painted Ladies much closer to the ground.
这是我们的飞行模拟实验 This is our flight simulator experiment.
做法是把蝴蝶绑在一根细棍上 What we are done is we've.. butterflies to find road.
然后放进这种飞行模拟器 And put them inside these flight simulators.
模拟器跟电脑连接 蝴蝶随时可以转向 There are ridged up to computer and the butterflies are free to turn.
它们一转弯就会被记录下来 And as they turning, we recording that turning,
这样就能画出它们自由飞行时会采取的路线 and we can acctually draw out the flight path they would've taken if they free fly.
这桶子让蝴蝶看不见周遭的风景 Tha barrel blocks the butterfly's view of surrounding scenery
排除所有潜在的分心事物 removing any possible distractions.
唯一的参照点是上方的天空 The only reference point they have is the sky above.
惊人的是这些蝴蝶一再选择相同方向 Remarkably the butterflies consistenly choose a common direction.
这些是飞行方向 每一个点都代表个别蝴蝶 These are the flight headings each spot is one individual butterfly
和它们飞行的整体方向 and the overrule direction they went in.
可以看到这些蝴蝶平均是往南飞 So you can see that on average my butterflies were flying to South.
我们发现，如果把模拟器盖住，让它们看不见天空 What we found, when we put a lid on simulator so they could not see the sky,
正如这图标显示的，它们就不知道要飞向哪 is as you see they did know in which direction to go in.
它们无法维持南向飞行 They would not able to maintain southwest heading.
瑞贝卡的结论是，它们选择这种航向的能力 Rebecca concluded that their ability to choose this heading
必定跟它们能在上方天空，看到的唯一事物有关 must depend one thing they can see in the sky above.
太阳 The Sun.
太阳确实是很棒的提示，它横越天空的行动很容易预测 Actually the sun is really good cue, it is very predictable and is movements accross the sky.
蝴蝶都是在有出太阳天气温暖的白天飞行 And butterflies will be flying in the middle of the day when there is warm
那段时间太阳都是在南边 until the Sun is out and this must be a South at that time of the day.
对蝴蝶来说这是清楚指出南方的明确提示 So it is very good sign for butterflies to know which way is South.
这种内建罗盘让小红蛱蝶 These inbuilt compass allows Painted Ladies
能在高空飞行时选择南风 at hight altitude to select a wind which heading South.
因此得以在漫长的回程搭便车，一路飞回非洲 So it is a free ride at long return jorney all the way to Africa.
有些昆虫面对完全不同的挑战，不是长程飞行 Some insects face a very different challenge, not fly long distances,
而是在黑暗中飞行 but flying in the dark.
灯光诱捕器可以吸引这些夜行飞行者当中最特别的几种 A Light Trap can attract some of the most remarkable of this nocturnal flyers.
蛾 Moths.
蛾演化成在夜间飞行或许是为了躲避掠食动物 Moths probably evolve to fly at night to avoid predators.
它们的眼睛已适应微弱光线，它们还能使用第二种高度发达的感官---嗅觉 Their eyes are adapted to low light, but they also use a second highly develop sense---smell.
这是公天蚕蛾 This is a male Moon Moth.
蛾的两对翅膀交叠方式与蝴蝶一样 Moths overlap their two pairs of wings in just the same way Butterflies do,
这个品种的蛾非常特别，它的寿命极短 and this particular moth is very special. It has an extremely short life.
只有大约一周，它甚至不会进食 It will only live for a week. It won't even feed.
它唯一的目标是找到异性 Its only object is to find a female.
而且它是靠这对类似羽毛的敏感触角寻找 And it does that with these remarkable feather-like antenna.
母蛾会发出独特的明显气味 The female emits a particular characteristic scent,
透过那对触角，公蛾最远在1英里外就能感应到 and with those antenna, the male can sense it from as much as a mile away.
它会马上飞往风处，直到找到那气味的源头 It then take-off and fly upwind, until eventually it find the source.
前后翅交叠的蛾类也是顶尖飞行者 Moths with their combined front and rear wings, are also excellent flyers.
有些寿命较长的蛾需要飞行觅食 Some live longer, and so need to fly to find food.
这只飞蛾最爱的食物是花蜜 This Sphinx Moth favorite food is nectar.
它甚至能在吸食时悬停 It can even hover as it drinks.
透过交叠的两对翅膀 So by overlapping their two pairs of wings,
蝴蝶和蛾类成为技术一流的飞行者 Butterflies and Moths has become very competent flyers.
但有一群飞行昆虫 But there is one group of flying insects that has change
把它们的后翅膀变成彻底不同的器官 the back pair of wings into something quite, quite different.
这器官让它们能做出最不同凡响的花式飞行动作 Something that enable them to perform the most extraordinary aerial gymnastics.
飞行昆虫的故事已经进入最后章节，我要回到伦敦 For the final chapter in our story of flying insects, I'm returning to London.
都市丛林和里面的人类居民，为一种适应力高强和数量众多的昆虫 The urban jungle and its human inhabitants provide plenty of shelter and food
提供充足的庇护所与食物 for a particularly adaptable and numerous kind of insect.
非常感谢 谢谢 Thank you very much. - Thank you.
像这样的诱人餐点，我确定 An inviting meal like this one, well I'm quite sure,
马上就会吸引一种飞行食客，它是所有飞行昆虫当中 very soon attract a flying diner, that is one of the most remarkable
最厉害的一群 of all insects aeronauts.
那当然是苍蝇 It is of course a Fly.
绿头苍蝇这个品种，分布遍及全球 This particular kind, a Blow Fly, occurs all over the world.
它的祖先至少从2亿5千万年前，就像这样嗡嗡乱飞 And its ancestors have been buzzing around for a least 250 million years.
苍蝇太过常见，人们一般只把它们当作讨厌的害虫 Flies are so common, we tend to dismiss them as just irritated pests,
但它们的飞行能力非常了得 but their flying abilities are truly remarkable.
来看看我用菜单打苍蝇会发生什么事 Watch what happen if I try and swat this one on the menu.
把这段画面速度放慢40倍，能看出苍蝇的动作有多灵活 Slowing down the action by 40 times, we can see how astonishingly agile Flies are.
在我眨眼的一瞬间它就逃走了 It make its escape in the time it take me to blink my eye.
在这种高速下扭转用来躲避敌人的能力 The ability to twist and turn at such high speeds, and so evade enemies,
让苍蝇成为现今全球性成功范例 has made Flies the global success that they are.
它们是昆虫界的喷射战机 They are the jet fighters of the insect world,
它们的灵巧性不是来自翅膀的形状 and they owe their maneuver ability not to the shape of their wings,
也不是因为肌肉有力，而是要感谢一组高度进化的飞行感应器 nor the power of their muscles, but to a set of highly advance flight sensors.
苍蝇拥有专属版本的战机仪表盘 A fly has its own version of a fighter pilot instrument-panel.
提供不断更新的速度，高度和航向资料 Providing constant update on speed, altitude and direction of travel.
苍蝇是透过眼睛收集这些飞行资料 A fly gather this flight data through its eyes,
而且它们拥有昆虫界最精密的眼睛 and these on among the best in the business.
苍蝇眼睛处理视觉资讯的速度比人类眼睛快了10倍 They can process visual information around 10 times as fast as our own eyes.
但高速飞行时，连苍蝇眼睛 But in high speed maneuvers, even a fly eyes
都难以处理一项关键飞行资料 struggle with one crucial piece of flight data.
那就是身体在空气中的角度，以及改变角度的方式 The angle of its body in the air, and the way it changes.
人类飞行员是靠陀螺仪得以上资讯 Information that a human pilot will get from an instrument based on a Gyroscope.
如果要做出这样的特技，那些资讯不可或缺 And that is essential if you going to pull-off a stunt like this one.
幸好，苍蝇不只有眼睛作为导引工具 Fortunately, Flies not only have eyes to guide them.
它们还有更加精巧的第二组感应器 They also have a second and even more remarkable set of sensors.
那是从四片翅膀的原始设计分化而来 One that it derived from that original four wing design.
苍蝇只有一对翅膀 A fly only has a single pair of wings.
它们的后翅已经转变成另一种器官 The rear pair have been converted into something else.
名为平衡杆，类似棍棒的小附肢 A tiny club-like appendage known as a haltere.
这种极为精密的器官能警告飞行中的苍蝇 This surprisingly sophisticated organ alert the fly for changes
改变身体的位置 in the position of its body in the air.
苍蝇在起飞后，两根平衡杆开始上下移动 As the fly takes-off, each haltere begin to beat up and down,
因为速度飞快，立刻就变成一团残影 and so fast, it immediately becomes a blur.
但慢动作播放，就能看见平衡杆像钟摆一样来回晃动 But in slow motion, we can see that it swing back and forth like a pendulum.
为了解平衡杆的运作 To understand how the haltere works,
必须追踪它的空中翻滚动作 we need to track its movement in the midair roll.
平衡杆的加重顶端有惯性动作 The weighty tip of the haltere has a kind of moving in arched,
所以在苍蝇侧翻时会保持同样的摆路径 so, that it remain on the same swinging path as the fly banks.
身体跟平衡杆之间的角度现在已经改变 Now the angle between the body and the haltere changes,
平衡杆的底部变得绷紧 and the base is put under stray.
感应器被启动，侦测到翻滚动作 This triggers sensors which register the roll.
苍蝇接着就能调整拍翅，也能校正不平衡的状态 The fly can then adjust its wing beat to correct any imbalance, however extreme.
伦敦帝国学院正在进行一项新研究 New studies into a second remarkably use of the haltere signal
锁定平衡杆讯号的第二种惊人运作 are taking place at London Imperial College.
生物工程系的专家在研究绿头苍蝇 In the department of Bioengineering, experts are studying Blow Flies
想知道它们的天然飞行机制 to see if their natural flight mechanics can improve the performance
能否改善人造飞行器的性能，例如这架无人机 of man-made flyers, like this drone.
苍蝇的动作非常灵巧，观察它们互相追逐的性能表现 Flies are incredibly maneuverable, and if you look at their performance,
会发现几乎没有其他动物 one chasing another one, it's really hardly
能够比拟这种空气动力的性能 any other animal that can match this sort of aerodynamic performance.
贺格尔设计一项实验，调查苍蝇的平衡杆和另一种飞行感应器 Holger has devised an experiment to investigate an intriguing connection
也就是它的眼睛之间的复杂关联 between a fly halteres and it other key flight sensor, its eyes.
他用一具小马达模拟一系列高速空中翻滚动作 A tiny motor simulate a series of high speed midair rolls.
并且以一台特别摄影机记录苍蝇的反应 The way the fly then reacts, is recorded on a specialist camera
接着就能用慢动作重播画面 which can replayed the action in slow motion.
如果仔细观察，你能看到苍蝇的头一直保持着水平 As you can see if you look closely, the head of the fly is maintained level,
身体会转动，为保持水平视线 the body is rotating, and to maintain level gaze
它们必须反转头部 they have to counter-rotate the head.
为了收集正确的飞行资讯，眼睛一定要保持水平 Keeping the eyes level is vital, if they to gather accurate flight information.
平衡杆已经被确认是它们能做到这点的关键感应器 And the halteres has been identified as the crucial sensor that makes this possible.
光靠视觉系统会太慢了，所以才要动用平衡杆 Visual system alone will just be to slow, that's where actually the halteres coming.
平衡杆的反应速度极快 The halteres are extremely fast in terms of their responses,
它们能够立即发出讯号，送到颈部运动系统 and they are immediate will signals, that are then sent to the neck motor system,
以及飞行运动系统，它们是率先用来修正 and to the flight motor system, they are the first really
任何干扰的器官，只要能做到这点 to compensate for any disturbances, and if that has happened,
视觉系统就能够专心用来解决其它的问题 the visual system is perfectly well situated to cope with the rest.
所以苍蝇失去一对翅膀，但取得一组绝佳的新飞行感应器 So, Flies lost a pair of wings, but gain an extraordinary new flight sensor
这让它们成为昆虫界最先进的飞行者 that made them the most advance flyers in the insect world.
飞行能力让全体昆虫取得全球性的惊人成功 Flight has enable the insects as a all to become an astonishing global success.
昆虫品种是其它 There are twice as many insects species,
所有动物加总后的2倍多 then there are of all other animals put together.
它们的伟大演化故事 Theirs is a remarkable evolutionary story
涵盖3亿2千万年时光 that spans over 320 million years.
从最早来自水中的四片翅膀生物 From the first four wing creatures that emerge from the water,
到离开水域移居大陆的硬壳甲虫 to the armour-plated Beetles which colonise land away from water.
从拥有巨大多彩翅膀的蝴蝶 The Butterflies with their huge colorful wings.
到技艺惊人的飞行高手苍蝇 And the stunningly skillful aerobatic Flies.
但拥有技术或许还不够， 有时体形就是一大优势 But skill may not be enough, sometimes sheer size counts.
昆虫继续独占天空大约1亿年 The insects had the skies for themselves for around 100 million years,
但接着出现一种新的动物，它们的身体可以长到更大 but then a new group of animal appeared, animals that could build bigger bodies,
而且将把飞行技术提升到更高的层次 and they were to lift the techniques of flying to even greater heights.
随着这趟回到过往的旅程继续进行 As our journey through time continues, we encounter
我们将见到新一波 大型飞行动物的非凡先锋 the extraordinary pioneers of a new wave of larger flyers.
有体形庞大的有翅爬虫类 Monstrous winged reptiles.
全身长满羽毛的怪异恐龙，它们大胆探索天空成为鸟类的祖先 Strange feather dinosaurs, who ventures into the air led to the birds.
以及一群征服漆黑夜晚的哺乳动物 And a group of mammals that conquered the pitch-black of the night.
蝙蝠 The bats.
大卫·爱登堡倾情奉献 Written and Presented by David Attenborough
我们人类很晚才飞上天空 We human beings are very latecomers to the skies,
我们或许自认现在的飞行技术不错 and although we might think that we now pretty good at this,
但大自然在数百万年的演化协助下 the Natural World, with the help of several million years of evolution,
制造出让人眼花缭乱的多种飞行动物，拥有远远超越人类的飞行技能 has produce a dazzling range of aeronauts whose talents are far beyond our.
动物成功占领天空的故事令人拍案叫绝 The story of how animals manage to colonise the air is truly astonishing.
首先升空的是昆虫 First into the skies were Insects,
它们起初有两对翅膀 they initially had two pairs of wings
随着时日推移，演变出许多不同形态 which in due course were modified in many different ways.
但在独占天空约1亿年之后 But after having had the skies for themselves for about 100 million years,
有新的一群动物飞上空中 a new group of animals took to the air,
它们是脊椎动物，也是有脊骨的生物 Vertebrates. creatures with backbones.
它们面临不同的挑战，它们的身体更大也更重 They faced a different challenge, for their bodies were much bigger and heavier.
但最后它们演化出几种解决这问题的方法 But eventually they evolve several ways of solving that problem.
我们将走遍全球 We will travel the globe to trace the details
追踪飞行脊椎动物拥有的非凡技术的细节 of the extraordinary skills of the backbone flyers.
征服天空 ~ Conquest Of The Skies ~
飞行对手 RIVALS
这里是婆罗洲 This is Borneo.
这里仍然保留大片的原始雨林 And here there are still great tracks of pristine rainforest.
这种森林住有种类繁多的动物 Forest that is wonderfully rich in animals of all kinds.
绞车把我拉上这里最高的一棵树 I'm being winch up into one of the tallest trees here,
我要寻找或许能给予提示的一种动物 in search of a creature that can give us a hint
让我们明白脊椎动物最早怎么飞上天空 of how backbone animals first took to the air.
藏身在高处树冠层的蕨叶里面 Hidden among these leafs of this fern, high up here in the canopy,
是一种神奇的小蛙 is a very remarkable little frog.
它是红腹树蛙，它的攀爬技术很高明 It's a Harlequin Tree Frog, and it a very-very good climber.
一生多数时间都在这高处树枝间爬走 It spend most of its life up here, clumping around in the branches.
在这里它能避开在林地里 Here it's away from the numerous predators there are,
会攻击它的许多掠食动物 that might attack it down on the forest floor.
但如果真有掠食动物能来到这么高猎捕它 But if in fact, a predator were able to get up here, to hunt it,
或许是一条蛇，这红腹树蛙它有个绝妙的自卫方法 a snake perhaps, well, the Tree Frog has a remarkable trick for defense.
它会滑翔 It glides.
它长长的脚趾之间有蹼 It has membranes between greater elongated toes,
把每个脚掌都变成降落伞减缓下降速度 so that each foot becomes a parachute which slow the frog descent,
也让它得以安全降落 and so enable it to make a relatively safe landing.
脊椎动物约在2亿6千万年前首次尝试升空 The Vertebrates made their first forage into the air around 260 million years ago,
很有可能一部分飞行先驱正是用皮膜 and it very likely that some of these pioneers use skinny membranes
就类似这只小树蛙的作法 to control their falls in much the same way as this little frog does.
就事论事，它不算是顶尖飞行员 It has to be said that is not a very good aerial navigator,
看来它顶多是跳下来滑翔而已 it seems that it just jumps and hopes for the best.
但是在高处，有些动物可以在树木之间滑翔 But there are animals up here, that glide around from tree to tree,
它们都是高明的飞行者 which are very good navigators indeed,
能靠绝佳飞行技巧在森林里来去 so good in fact, that they can go from one tree to another
一辈子都不用下去地面 and never go down to the ground in their entire life.
其中之一是裸耳飞蜥这种小蜥蜴 One of them is a little lizard called Draco.
每只公蜥在树上都有自己的小地盘 Each male has his own little territory in the branches,
它吸引母蜥和吓退对手的做法，是秀出自己的肉垂 and tries to attract females and warn off rivals by flashing his dewlap.
它也会张开侧腹的皮膜 He also spread colored flaps of skin from his flanks,
这在完全伸展时作用跟肉垂差不多 that when fully extended do more or less the same thing.
但树上会有掠食动物出没 But there are predators among the branches.
蛇也住在树冠层，它们会猎食蜥蜴 Snakes also live up here, and they hunt Lizards.
裸耳飞蜥的侧腹皮瓣现在要发挥另一种作用 But Draco side flaps now serve another purpose.
它把长长的肋骨往前推，张开皮膜滑翔 He uses them to glide by hinging forward a specially elongated ribs.
它的飞行技术一流，可以控制方向 And he so skilled in the air that he can steer land
降落在看中的树干上 on the trunk of his choice.
如果你住在树上靠飞行移动 So, if you live up in the branches it's less laborious,
会比爬下树到地面更省力，也安全许多 and indeed, safer to travel by air, than to come down to the ground.
但如果想成为真正的飞行者，不只要能往下飞 But if you want to be a true flyer, you have to be able to fly
也要可以往上，你必须要能进行动力飞行 not only downwards but upwards, you have to have powered flight.
这个是另一种爬虫类 This is another reptile,
它的飞行能力比会滑翔的小飞蜥更强 and one with even greater flying abilities than that little gliding lizard.
不幸的是，今天它已经绝种了 Today, sadly, it's extinct.
这是双型齿翼龙，从化石可以推论出 This is Dimorphodon, we can deduce from its fossils
它有拍翅所需的肌肉 that he had the muscles needed to beat its wings.
电脑动画能让我们见到它的真面目 And computer imagery can show us what he must was look like.
双型齿翼龙是史上最早飞上天空的大型动物之一 Dimorphodon was one of the first large animals ever to travel by air,
时间在2亿年前 200 million years ago.
它是一种翼龙，也就是有翅爬虫类 It belong to a group called the Pterosaurs, The Winged Reptiles.
它应该是生活在森林里而且是住在树上的 It was probably a forest dweller and it descendant of a tree living glider.
它是滑翔动物祖先，有跟裸耳飞蜥一样的飞膜 This gliding ancestor might have had wings like those of Draco,
而且或许是从手指延伸到脚踝 that was made of skin, and perhaps extended from its fingers down to its ankles.
但翼龙演化出更大的飞膜，搭配有惊人长度的第四根手指 But Pterosaurs have evolved larger wings with a hugely elongated fourth finger.
飞膜内部有细长的硬组织加以强化 The wing membrane was strengthen internally by thin rods of a stiffer tissue.
还有肌肉纤维，让飞膜能在飞行时改变形状 They were muscles fibers too, that enable it to modified its contours as it flew.
检视飞膜切片就能知道它们的效率秘诀 Looking at the wings insection revealed a secret of their efficiency.
它有弧形前缘和尖形后缘 They have a rounded front edge and a sharp back edge,
这种形状成为翼形 a shape known as an aerofoil.
这能迫使流过飞膜上方的空气提高速度 It's works by forcing the air flowing above the wing, to speed up.
这道较快的气流压力较低，所以飞膜会被往上吸 This faster air has a lower pressure, and the wing is suck upwards.
飞膜表面积越大，能制造的升力更强 The larger the surface area of the wing, the greater lift it can produce.
看来翼龙绝对是技巧高超的飞行者 So, it seem certain that Pterosaurs were very competent flyers.
而且从牙齿判断，很多翼龙可能是吃种类繁多的昆虫 And judging from their teeth, it's seem likely that many fed on the great variety of Insects
它们比翼龙更早飞上天空 that had preceded them into the air.
昆虫独占天空约1亿年 Insects have had the skies to themselves for around 100 million years.
现在出现了更大的生物---爬虫类 Now, bigger creatures had arrived. ---Reptiles.
结果证明，翼龙的飞行机制大为成功 The Pterosaurs design for flight proved hugely successful,
它们使用这种新能力扩展到森林以外的地区 they use that new powers to spread beyond the forests
移居到各种全新的环境 and colonize whole new environments.
许多翼龙都在水边生活和觅食 A great number of them lived and fed near water.
我们知道这点是因为很多种翼龙的化石 We know this because fossils of many species
都是曾经位于湖泊和浅海底部的泥土 occur in rocks that was once mud at the bottom of lakes and shallow seas.
这个化石上的动物残骸有1亿5千万年的历史 This one shows the skeleton of little animal that 150 million years ago
它坠落在一座浅泻湖的底部 fell to the bottom of a shallow lagoon.
这是它的头，它的脊骨 This is its head, here is its backbone,
尾巴，后腿 tail, hind legs,
从长长的指骨延伸出来的这片就是它的飞膜 and here stretching from these long extended finger bones are its wings.
这个化石特别与众不同 And this fossil is particularly remarkable,
因为这片飞膜印痕显示出极为清晰的细节 because it show an impression of the membrane in extraordinary detail.
看得到所有细小皱褶 You can see every little tiny fold.
透过骨头可以研判动物的生活方式 You can judge how an animal lived by its skull.
这只翼龙有很长的颚骨 And this one, have these long jaws,
搭配往前伸的牙齿，我们认为这就表示 with forward pointing teeth, and we think that this indicates
它是靠飞掠过泻湖海面 that it lived by skimming across the surface of the lagoon,
抓鱼维生，它的牙齿可以用来叉鱼 and snatching up fish with impaled on those teeth.
这只很不一样的翼龙只有头部化石 This, very different one, it's just the head.
可以看到它的颚骨很长 As you can see has very long jaws
下颚的尖端有一小撮很细密的丝状物 and on the tip of the lower one is this little tuft of very fine filaments.
我们从其他化石得知 We know from other specimens that these filaments
这些丝状物本来就是分布在整根颚骨 originally stretch right along the entire jaw.
这种硬刷式边缘能让它进行滤食，先含着一口的水 This bristely fringe enable the creature to filter feed, taking in a beak full of water,
把喙半闭，透过硬刷排水 expelling it through the bristles with the beak half closed
然后吞下被硬刷挡住的东西 and then swallowing what the bristles retained.
这个更大品种的头骨是来自巴西的化石 And here's is a skull of a very much bigger species from Brazil.
它的下颚没有牙齿，也没有硬刷 And it had neither teeth nor bristles in this jaws.
但用显微镜检查这块骨头的表面 But microscopic examination of the surface of the bone here
发现有细小的血管 reveals very tiny little blood vessels
表示这些颚骨原本是被骨质喙部包覆着 and that suggests that this jaw was once covered with horny beak.
或许这只翼龙的喙部就像一个镊子 So maybe this animal used it's beak like the forceps
可以夹住小型爬虫类或抓住飞行中的蜻蜓 to pick up small little reptiles or maybe catch dragonflies in the air.
这个骨头也揭露了这种翼龙生活方式的另一特色 This particular skull reveals something else about the lifestyle of this specimen.
因为它的头骨后方有着一大块凸缘 Because of the back of the scull it has this great flange.
目前发现的其他品种翼龙头骨 And Pterosaur from other species
有些有这种凸缘但其他没有 have been found some with such flanges but others without.
有个推论是这或许是出于性别差异 So it's tought that maybe this was the difference between sexes.
也许公翼龙的后脑才有这种大凸缘用来做展示 Maybe was the male that had this big flanges backwards to display them.
也许有皮肤包覆，我们只能猜测 Maybe was covered with the skin. We can only guess.
很多不同品种的翼龙都演化出这种头冠 Many different pterosaurus species evolved these headcrusts
而且这些头冠很可能是彩色的 and seems very likely that they were colored.
这个拥有华丽头冠的品种叫古神翼龙 This spectacular example is known as Tapejara.
它们在内陆湖湖畔筑巢 And it made it's home beside inland lakes.
但翼龙在其他方面也有差异，有些演化出较大的身体 But Pterosaurs diversify another ways too. Some evolved much larger bodies.
这个品种的翼展超过20英尺，等于7米 This species had a wingspan of over 20 feet, 7 meters.
但不是所有翼龙都住在森林里或水边 But not all Pterosaurs lived in the forests or near water.
像这样的开阔旱地 An open arid landscape like this one, was the likely home
可能是一种最不同凡响的翼龙栖地 of one of the most extraordinary.
大约在7千万年前 Around 70 million years ago a pterosaur appeared
出现了一种体形极为巨大的翼龙 that was of truly colossal proportions.
那是史上最大的飞行生物之一 That was one of the largest creatures that had ever flown,
它的体形相当于一架小飞机，它叫风神翼龙 it was in the size of a small airplane, and it was called Quetzalcoatlus.
巨大翼展让它能驾驭 Its immense wingspan allowed it to ride on the currents of warm air
从高温陆地升起的暖空气 that rise up from sun heated land.
于是能够长程滑翔，到处觅食 It could then glide great distances, searching for food.
它的目标是蜥蜴等小动物，或是恐龙等大型动物的尸体 Small creatures like lizards, or the dead bodies of much larger ones, Dinosaurs.
但拥有坚韧皮肤形成的飞膜的翼龙 But the Pterosaurs, with their wings of toughen skin
不是在远古天空飞行的唯一爬虫类 weren't the only group of reptiles to make it into those ancient skies.
约在1亿5千万年前 About 150 million years ago, another reptilian group appeared
另外一种也会飞的爬虫类在地球出现 on the Planet that also flew.
跟大多数爬虫类一样，包括翼龙 Like most reptiles, including Pterosaurs,
这些生物是以卵孵化的 these creatures began their lives inside an egg.
但它们已经演化出革命性的新飞行机制 But they had evolved a revolutionary new design for flight.
这将在我们的故事中创造伟大的全新章节 One that would usher in a remarkable fresh chapter in our story.
跟翼龙不同，它们今天仍然生活在地球上 And unlike the Pterosaurs, they still with us today.
它们当然就是鸟类 There are of course the Birds.
现在有些鸟能提供线索 Some today can provide clues about how their ancestors
指出它们的祖先是怎样成功飞上天空 manage to get into the air.
这是在各地农家庭院都能见到的鸟类雏鸟 This is the chick of a bird found in farmyards everywhere.
这是一只母矮鸡 A Bantam Hen.
在这个生命的初期阶段，就能提供一条有趣线索 And at this very early stage in its life, it can show us something very interesting
指出一种重要飞行器官的起源---羽毛 about the origin of that crucial piece of flying equipment---A feather.
它的羽毛是绒毛，也就是说它们是以简单的细丝组成 Its feathers are downy, that to say they made up of simple filaments,
绒毛的功能不是飞行，而是隔热 and their function is not for flight, but insulation,
用来帮这只小生物保暖 to keep this little creature warm.
回到侏罗纪，早在真正的鸟类出现之前 And back in the Jurassic period, long before the arrival of True Birds,
有一种完全不同的动物长出外形类似的羽毛 very similar looking feathers appeared on very different animals.
爬虫类 精准地说是恐龙 Reptiles. Dinosaurs if to be precise.
为了寻找这个惊人说法的证据 To find evidence for that astonishing statement,
在不久前这里仍具有高度争议性 我们要前往中国 which not so long ago was highly controversial, we heading for China.
在中国长城东北方，蒙古交界附近 Northeast of China's Great Wall, near the borders of Mongolia,
是气候寒冷的辽宁省 lies the chilly province of Liaoning.
这里有大片岩石地带 Here, there are great areas of rocks that was lay down as mud
过去曾是多座辽阔水湖湖底的泥沙 in the bottom of immense fresh water lakes.
被冲进这些湖里的动物尸体 The bodies of animals that was swept down into these lakes
慢慢被颗粒细小的沉积物掩埋 was slowly entombed by the fine grains sediment
完整保存下来，留住精密细节 that preserved them entire and in exquisite detail.
从这些化石发现的许多样本 And from these rocks have come specimens
解决了最常引发激辩的演化争论之一 that solve one of the most hotly debated of evolutionary arguments.
那就是鸟类的起源 The origin of the Birds.
其中最重要的化石目前在北京 The key specimens are now in Beijing,
在这里用显微镜进行谨慎处理 where they been delicately prepared under the microscope.
全球最著名的恐龙专家在这里研究这些化石 They have been studied here by one of the world greatest Dinosaurs experts,
徐星教授 professor Xing Xu.
他先向我展示最古老的化石之一，这是恐龙前肢的一部分 First, he showed me one of his oldest specimens, part of a Dinosaur arm.
多亏了那些古湖泊的细沙 But thanks to the finest of the mud of those ancient lakes,
这个化石不只有骨头 there is more here than just bones.
看这，这个化石叫北漂龙 You see here, this species it called a Beipiaosaurus,
它十分不像我们，它的身长有2到3米 So, because this is a very not like us, two or three meters long,
所以是很大的动物 这是前肢，手掌，看这... so quite a big animal. And here is an arm, hand, you see here...
暗色的丝状结构... --对 dark filamentous structures... - Yes.
沿着前肢和手掌分布，这些其实是原始羽毛 along that arms and hand, they are actually primitive feathers.
那些羽毛非常简单，非常简单 And those feathers very simple, very simple,
所以我们认为那是代表着羽毛演化史的原始阶段 so we believed they represent the very primitive stage for feather evolution.
这些简单羽毛的材质跟今天鸟类的羽毛相同 These simple strands were made of the same material as the feathers of today Birds.
外形相对较粗，所以一定很硬 They were relatively thick and must have been quite stiff,
它们应该会从恐龙的前肢伸出来 so they would of stuck out beyond the dinosaur arm.
在这些羽毛的后方是覆盖全身的较短羽毛 Behind them, were shorter strands that covered its all body.
就跟小鸡的绒毛一样，这些应该是用来帮恐龙保暖的 Like the down on the chick, these might have kept the dinosaur warm.
但那些长羽毛很可能有不同功能 But those long strands most likely had a different function.
关于这些长羽毛功能的线索可以在一个更特别的化石上找到 Clues to what that might have been can be found on an even more extraordinary fossil.
这些爪子和指骨是属于名为尾羽龙的生物 These claws and finger bones belong to a creature called Caudipteryx.
周围的暗色形状是羽毛痕迹 The long dark shapes around them are the remains of feathers.
这里的单根羽毛结构更加复杂 The single strands are here rather more complex.
在羽轴两侧都有细丝状的羽枝 They had barbs, thin filaments attached to either side of a central rod.
这看来就像是鸟类的羽毛 This look more like a bird feather.
尾羽龙每条前肢都有约26根羽毛 Caudipteryx had around 26 of them along each arm.
这看起来或是翅膀，但这些羽毛并不长 This may look like a wing, but the feathers were not very long.
跟这只恐龙的身体和长腿做比较，答案就很清楚了 And when you compare them to the size of this creature body, and its long legs, it's clear
这些羽毛显然不够大，无法让尾羽龙飞起来 that they weren't big enough to enable Caudipteryx to fly.
所以这些羽毛的作用是什么？ So, what were these feathers for?
显微镜检查发现这些羽毛是彩色和有花纹 Microscopic examination has revealed that they were colored and patent.
所以这些羽毛或是展示用的 So, maybe they were used for display,
也许在求偶时挥舞，用来吸引异性 perhaps to wave around during courtship to attract a mate.
不过看来它们对尾羽龙也有其他用途 But then is seems that they also helped the dinosaur in a different way.
通过观察某些现代鸟类的雏鸟 We can find a hint of how they might have done this,
运用羽毛的方法就能找到线索 by watching the way some young birds use their first feathers today.
这些是10天大的小雉鸡 These are ten day old Pheasant chicks.
它们的羽毛还没长齐 Their feathers are not yet fully developed.
这阶段的雉鸡羽毛结构跟尾羽龙的羽毛很类似 At this stage they similar in structure to the feathers on that dinosaur, Caudipteryx,
而且是以相同的方式在每条前臂长成一排 and going aline along each arm in much the same way.
但这些初羽也一样太短，无法让它们飞行 But these early feathers are also too short to enable these creatures to fly.
不过它们还是很有用 Nevertheless they very helpful.
小雉鸡是在地面的鸟巢孵化 Pheasant chicks has to nest on the ground,
但它们很快就得爬上栖木以避开掠食动物 but they soon need to roost high up, where they are be safe from predators.
拍打它们的简单翅膀能让雏鸟获得些许额外升力 Flapping these simple wings gives the chicks a little extra lift
帮自己爬树 to help them climb into a tree.
等到要回去地面的时候 And when the time comes to return to the ground,
这些初羽也能再次帮上忙 those first feathers again are a help.
它们没有能留住空气的宽大表面 They don't provide a large air-catching surface,
但足够让雏鸟放慢降落速度 but they enough to slow a chick fall,
稍微减轻降落力度 and make that landing just a little softer.
或许恐龙的羽毛起初是用来保暖 Maybe the feathers that had initially kept the Dinosaurs warm,
后来也帮它们飞上天空 now also help them to get into the air.
然后，只几年前 And then, only a few years ago,
在辽宁的泥岩里又找到另一个非凡物种的化石 the mudstone of Liaoning produce yet another extraordinary fossil.
它被命名为小盗龙，它显然是一只小恐龙 It been named Microraptor, and it clearly a small dinosaur.
但这个化石特别引人注目，是因为它的羽毛 But this specimen it particularly exciting, because of its feathers.
它的前臂有羽毛 Feathers on the forearm there.
后肢有羽毛 Feathers on its hind limbs.
甚至在很长的尾巴的尾端也有羽毛 And even feathers right at the end of its very long tail.
但这些羽毛与我们 But there is something that makes these feathers
刚才见过的恐龙羽毛有一个不同的地方 different from any other feathers you seen on Dinosaurs before.
这些羽毛的羽根有一侧比较窄 They are narrower on one side of the quill than on the other.
跟鸟的羽毛一样 Just like bird feathers.
内部显微构造显示它们带有虹彩 Microscopic structures within them suggest that they had flashes of iridescence.
所以这些羽毛应该是用来展示的 So, these feathers were probably use for display.
但它们的不对称形状是飞羽的特征 But their asymmetric shape is characteristic of flight feathers.
流过羽毛狭长前缘上方的空气能制造升力 The air flowing over the narrow front of the feather can produce lift.
那这种外形奇特全身长满羽毛的恐龙真的能飞吗？ So, could this strange looking dinosaur with feathers all over it actually fly?
有人认为它后腿上的羽毛 Some people think that those feathers on its hind legs
或许会让它不方便在地面行走 would have made it rather difficult for it to walk around on the ground,
而它应该是比较善于攀爬 and that it would had been more at home climbing.
它的手指和脚趾上的爪子 And those claws on the fingers and toes
在爬树的时候显然大有帮助 are obviously very helpful in climbing up tree trunks.
但形状符合空气动力学的羽毛确实指出 But those aerodynamically shape feathers certainly suggest
它的前肢是用来当作翅膀 that its arms were been used as wings.
这只四翼恐龙在当时一定是非比寻常的动物 This four wing dinosaur must had been a really extraordinary animal.
它的前翅够宽，能让它滑翔 Its front wings were broad enough to enable it to glide,
它的胸产肌肉也够强壮 and its muscles on the chest were sufficiently strong
能让它不时拍翅，帮助自己前进 to enable it to flap every now and then, and help it on its way.
但它后腿上的翅膀应该不会张开 But the wings on the hind legs were probably not held spread out,
而是留在身体下方用来协助转向的 but kept beneath the body to help the animal to steer.
现在这些恐龙 Now, clearly, these Dinosaurs were on their way
正准备加入翼龙飞上天空 to joined the Pterosaurs in the sky.
然后，同样在中国发现的化石 And then, discovered once again in rocks of China,
让我们看到被视为鸟类的生物 creatures recognizable as birds.
这是孔子鸟 这里总共有2只 This is Confuciusornis. There are two of them here.
它们已经没有长着牙齿的沉重骨质颚部 They no longer have heavy bony jaws sturded with teeth.
而是被没有牙齿的角质短喙取代了 Instead, they have a short beaks made of horn,
这能减轻重量 without teeth, lightweight.
它的尾巴不再有整排小骨头支撑 And the tail is no longer supported by whole chain of the bones.
那些骨头已经退化成这里的一小块残存物 These bones have been reduced to this tiny little stump here.
这是真正的鸟类 These are true birds.
但其中一个化石，在细长的尾巴上有长长的羽毛 But long feathers, attached to the tail one of this specimens
指出了这种原始鸟类的一个有趣特色 can reveal something intruiging about these early birds.
要查明这些羽毛的作用 To find out what they were for, we can look for a bird here in Borneo
可以观察婆罗洲一种有类似尾羽的鸟 that has very similar tail feathers.
这是大盘尾 This is the racket-tailed Drongo
它的尾羽跟远祖孔子鸟 and it's tail feathers there are astonishingly resembleance
拥有惊人的相似度 to those of a distant ancestors Confuciusornis.
这些羽毛在任何方面都看不出有助于飞行 They don't seem to help it's flight in any way.
所以它们对大盘尾来说一定有其他用途 So the drongo must be using them for something else.
展示 Display.
鸟类持续精进飞行技术的同时 And so, while birds continue to improve their flight
它们也继续利用羽毛求偶 they also continued to use the feathers in courtship
做法就跟它们的恐龙祖先一样 as their dinosaur ancestors had probably done.
但是鸟类不只是展示羽毛的形状 Birds use not just shape of their feathers for display
也会展示羽毛的颜色 but also their colour and this is really lovely examples of that.
在婆罗洲就有不少亮眼的例子 Here in Borneo.
这些鸟已经够鲜艳了，但有一种鸟的羽毛特别华丽 These birds are colorful enough, but one is particulary spectacular.
这是婆罗洲孔雀雉 This is the Bornean Peacock-Pheasant.
这只是公鸟 它的羽毛有醒目的鲜艳虹彩花纹 This is the male. His feathers are emblazing with colorful irridescent patterns.
那是因为它们是要用来吸引母鸟的注意 And that is because they used to attract the attention of a female.
相较之下母鸟的羽毛单调许多 Her feathers are comparatively drab.
公鸟先提供食物引诱母鸟进入它的求爱区 First, the male lures the female in to his courtship arena with the promise of food.
叼着蠕虫 The worm.
公鸟开始晃动身上的华丽羽毛 He becames to shake his magnificent feathers.
它清除地面上所有可能干扰表演的东西 He clears the ground of anything that might interfere with his performance.
当母鸟追着蠕虫进入求爱区，公鸟就张开所有羽毛形成一个大扇形 As the female dives in after the worm he raises all of his feathers in a huge fan.
如果母鸟认同它的展示，或许就会选择它当配偶 If she approves of his display she might choose him as a mate,
放弃其他公鸟对手 over other rival males.
最后母鸟带着它献上的虫离开 Eventually she makes off with the offering a food
看来它并未如公鸟期望般的被打动 it seems she was not as impress as she might have been.
所以轻量又能轻松立起的羽毛 So feathers, so lightweight, and so easily erected
可以作为宣示求偶和吓退对手的告示牌 can serve as billboards on which appertize for the mate or warn off rivals.
但要了解原始鸟类怎么运用羽毛达成动力飞行 But to see, how the early birds used their feathers to acheive fully powered flight,
我们得回到英国 we are returning to Britain.
在苏格兰尼斯的这个湖泊可以看到目前最令人叹为观止的飞行动物之一 And here, on the Lochs in Scotland we can watch some of the most majestic flyers around today.
黄嘴天鹅 Whooper Swans.
这群天鹅从一孵化就开始接触人类 These particular birds were in contact with human beings
所以愿意让我们靠近 from the very first moment of their hatched, so they allow me to get really close to them.
它们身上的小羽毛还是具有保暖的重要功能 The small feathers on their bodies are still essential for keeping their owners warm.
但这根是翼羽 But this one is a wing feather.
质地极为坚韧，但重量极轻 It extremely strong, but very light,
羽根两侧的细丝也就是羽枝 and the filaments on either side of the quill and the barbs,
全部紧密相接形成一片连续表面，强度足以撑住空气 zip together to form a continues surface which will strong enough to hold the air.
但这种大鸟在飞行时如果要靠空气支撑通过翅膀上方的气流 But if the air is to support a wing bird as it flies,
速度必须够快才行 it has to move over the wing very fast.
为了让气流变快，这些天鹅会加速掠过水面 And in order for that to happen, these Swans will move at speed
就跟飞机在起飞前滑行一样 across the surface of the water like an aircraft taxiing before take-off.
如果像这样贴近飞行中的鸟 When you close up to a flying bird like this,
就能看出它们的翅膀是一种复杂工程的神奇产物 you can see how a wonderful piece of complex engineering their wings are,
鸟能够改变翅膀形状和拍翅的速度 able to change their shape and their beat
因应周围气流的所有微小变化 to respond to every little change in the currents of the air around them,
用来把自己往前推进和往上抬升 and so propelled them forward and lift them upwards.
所以鸟的翅膀到底是怎么运作？ So, how the bird wings actually work?
检视慢动作画面就能仔细观察 If we slow them down we can watch in detail the mini subtle changes
翅膀上下拍动时的许多细微改变 they make as they move up and down.
羽毛重叠形成光滑的流线形表面 The feathers overlap to form a smooth contoured surface
可以伸展到比内部的骨头大上许多 that extends far beyond the bones within.
拥有弧形前缘和尖锐后缘的翅膀 With a curved leading edge of the front, and a sharp trailing edge of the back
是能制造升力符合空气动力学的经典形状 they have a classic aerodynamic shape that produced lift.
这就是翼形 They are aerofoils.
每当翅膀往下拍时，上方的气压就会降低 With this downward beat the air pressure above is reduced,
让鸟被往上吸 so that the bird is sucked upwards.
由关节相连的骨头和紧密的羽毛组成的这种翅膀 Wings like these consisting of jointed bones covered with closely fitting feathers
能做出细微精密的动作 can make very subtle delicate movements.
羽毛能紧贴着彼此滑动，让翅膀改变形状 The feathers slide over one another, so that when the wing changed its shape
但完全不影响表面的光滑 there is no loss of smoothness on the contour.
当天鹅在每次拍打之间稍微收缩翅膀 When the Swan slightly retract its wings in between beats,
滑动的羽毛可以确保翼形能继续制造升力 the sliding feathers ensure that the aerofoils still produces lift.
搭配轻量喙部和缩短的尾巴 As well as lightweight beaks and shortened tails,
还有已经变成中空的部分身体骨头 some of the bones of it's body became hollow.
造就出极具效率的轻量飞行动物 The result is an extremely efficient light weight flyer.
我们现在的时速为30英里 We are traveling around 30 miles an hour now,
但这些天鹅可以轻松加速随时把我们抛在身后 and yet these birds could easily accelerate and leave us behind if they wanted to.
从羽毛首次出现在恐龙身上以来 So feathers, since they're first appeared on the bodies of Dinosaurs,
已经取得几种不同功能 have acquired several different functions.
羽毛最早的作用是帮身体保暖 Initially they served to keep their owners warm.
接着有些羽毛变大还多了颜色可能是用来做求偶展示 Then, some grew large and acquired color and were probably use in courtship displays.
在那之后又经过数百万年 And only then, after millions of years,
羽毛才被用来飞上天空 where they used to help their owners get into the air.
约在1亿5千万年前，鸟类加入翼龙和昆虫飞上天空 So around 150 million years ago birds joined Pterosaurs and insects in the skies.
接着约在6千6百万年前，发生一场全球浩劫 Then, around 66 million years ago, came the global catastrophe
导致了绝大部分的生物在地球上彻底消失了 that triggered the disappearance of a vast proportions of the animal life of this Planet.
一颗小行星撞击地球是造成这场大灭绝的最可能原因 An asteroid hitting the Earth was the most likely cause of this mass extinction.
在随后而至的大灾难中，当时称霸地球的生物 In the devastation that followed, the dominants creatures of that age,
恐龙，从此消失 the Dinosaurs, disappeared.
翼龙全面灭绝 The Pterosaurs were completely wipeout.
只有少数鸟类幸存 And only a few of the Birds survived.
在一小段时间内，天空一定是显得无比空旷 The skies for a short period must have been relatively empty.
但之后，出现一种新的飞行动物 But then, a new kind of flying animal appeared.
这是一种毛茸茸的温血小型动物的大好机会 Now is a chance for a group of furry warm blooded little creatures,
数百万年来，它们都在恐龙脚下惊恐逃窜 that has been scampering around the feet of the Dinosaurs for several millions years.
那就是哺乳动物 They were the mammals.
最早飞上天空的哺乳动物当然是靠滑翔 The first of them to take to the air were doubtous gliders.
有一种存活至今的神秘生物 And one mysterious creature still alive today,
可以让我们得知那种动物的当年样貌 can give us an idea of what there were like.
这种生物住在婆罗洲的雨林，它叫鼯猴 It lives in the rainforests of Borneo, and it called the Cobego.
鼯猴有一大片毛皮覆盖的皮膜 It has an enormous blanket of furry skin that stretched
从头部侧面一路往下延伸到尾巴尾端 from the sides of its head right down to the very tip of its tail.
但是想要看它们怎么飞越空中，我们须等到晚上 But to see how he travel through the air, we must wait until nightfall.
它一旦降落，为补回落差，会在树上爬回原来的高处 As soon as it lands, it regain the height it inevitably lost by clambering up the trunk.
它是最出色的森林滑翔者 It by far the most skillful of the forest gliders,
一次跳跃就能跨越超过100米 and can travel over a 100 meters in one leap.
这毫无疑问是一种古老动物，有人认为从哺乳动物 It's undoubtedly a very ancient animal, and some believe that it may well
首次升空滑翔的远古时代 have survived virtually unchanged from that time long ago
它可能就保持原样存活至今 when mammals first took to the skies as gliders.
但哺乳动物很快就会有更好的飞行表现 But soon, the mammals deed better than that.
这个化石大约有5千2百50万年的历史 This is a fossil that dates from about 52.5 million years ago.
这是它的头，还有长齐的健全牙齿，脊骨和肋骨 Here its head, a very well develop teeth, backbone and ribs,
长长的尾巴，后腿，还有从我们的观点 a long tail, hind legs, and most importantly of all,
看来最重要的一点，手掌和大幅延长的手指 from our point of view, hands with enormously elongated fingers.
那些手指之间有蹼 And there was skin between those fingers.
这些是可以拍打的飞膜 These were wings and they could flap.
这是至今发现的最古老蝙蝠化石 This is the earliest fossil yet discovered of a bat.
没有证据证明蝙蝠的手指 We have new evidence to show exactly how a bat fingers
最早是怎么支持它们的翼 first began to lengthen to support their wings.
但透过观察它们的现代子孙，就能明白早期蝙蝠怎么飞行 But we can understand how those early bats flew, by looking on their modern descendants.
这是最大的蝙蝠 These are some of the largest.
由于体形庞大，通常被称为狐蝠 They so big, that they often called Flying Foxes.
它们的翼展超过1米 And they have a wingspan of over a meter.
像这样放慢蝙蝠的飞行动作，就能看见它拍翅时 When you slow a bat flight down like this, you can see that its four fingers
会张开四根手指确保飞膜被撑开和绷紧 are spread wide under down stroke, keeping the membrane wide and taut,
在抬起飞膜时则是收合手指，只留下顶端的拇指在外 and then clump together on the up stroke, with just a thumb off the top three.
这种折合飞膜的动作可以在每次拍翅之间降低它们的空气阻力 This folding of the wings reduces the bat air resistance between each beat.
为了让飞膜的尺寸最大化 To maximise the size of its wing, the back edge of the wing membrane
飞膜后缘是连在脚踝上 is attached to the ankles.
蝙蝠是以倒吊的姿态栖息 Bats roost by hanging upside down.
它们都是这样度过白天 And this is how they tend to spend their days.
据信最早的哺乳动物是昼伏夜出 Is thought that the first mammals were nocturnal,
这无疑是最佳作法 that doubtless was the best thing to be out of the way of the Dinosaurs
可以避开白天到处横行的恐龙 that were rampaging around during the day.
蝙蝠保留了祖先的夜行习性 So, the bats continue the nocturnal habit of their ancestors,
也继承了夜间行动所需的敏锐感官 and they are also inherited the acute sensors needed to move around at night.
它们的眼睛已经演化适应能靠微弱光线清楚视物 Eyes specially adapted to operating well in low light.
还有灵敏嗅觉让它们在黑暗中觅食 And an acute sense of smell that enable them to find food in the dark.
不论如何，鸟类已经称霸白天的天空 In any case, Birds already dominate in the daytime skies.
有飞膜和夜行感官的蝙蝠则是跨越全球成功繁殖 With their wings of skin and nocturnal senses the Bats became a hugh global success.
今天有超过1千100种蝙蝠占了所有哺乳动物品种的5分之1以上 Today there are over 1,100 species of them, that's over a fifth of all mammals.
所以到了5千万年前，已经有3种大型脊椎动物 So, by 50 million years ago, three groups of large backbone animals
加入与昆虫一起飞行 had joined the Insects in the air.
带头的先驱是爬虫类，也就是翼龙 The pioneers were reptiles, Pterosaurs,
它们拥有从纤长的手指延伸出的飞膜 with membrane of skin stretch from elongated fingers.
接着出现了一种恐龙，它们长出羽毛演化成鸟类 Then, came a group of Dinosaurs that acquired feathers and became Birds.
但当翼龙和恐龙在一场全球大灭绝中消失 But when the Pterosaurs and Dinosaurs were swept away in a global extinction event,
鸟类和新演化出的蝙蝠就占领了舞台 the stage was set for the Birds and the newly emerge Bats
准备争夺称霸天空的地位 between them to take command on the skies.
这两大类动物的每个品种都演化出独特的飞行技术 Each of these two groups had evolved its on techniques for getting into the air,
而且都注定要把这些技能带上惊人巅峰 and each was destined to bring theirs skills to astonishing extremes.
下一集要探讨鸟类如何适应与分化 Next time, we see how Birds adapted and diversified
成为现今遍布空中的各种杰出生物 to become the remarkable creatures we see in our skies today.
包括致命掠食动物... Lethal hunters...
队形飞行者...以及高空特技员 formation flyers... an aerial acrobats.
我们要探索蝙蝠如何发展出一种超级新感官 We explore how the Bats develop a new super sense
让它们能在漆黑的夜晚猎食 that enable them to hunt in the pitch-blackness of the night.
我们还要探访一个神奇的地点 And we visit one spectacular place were the battle for the skies,
昆虫、蝙蝠和鸟类的天空大战仍在那里继续进行 between Insects, Bats and Birds still continues.
大卫·爱登堡倾情奉献 Written and Presented by David Attenborough
我现在离地面有几百英尺高 I'm several hundreds feet up in the air,
在这里，我可能会碰到飞行的昆虫 虽然我还没有看到 up here, I might encounter perhaps a flying insect, although I haven't seen one yet,
甚至是吊在一条蛛丝上的小蜘蛛 or maybe even a baby spider clinging to a gossamer of thready silk,
它们就是靠吐丝到处飞的 但这里主要是鸟类的王国 which is their way of getting around. But by in large, this is the kingdom of the birds.
鸟类约在一亿五千万年前首次飞上天空 The first birds flew about 150 million years ago.
它们遍布全球，深化出五花八门的不同种类 They spread around the globe, and evolved into a multitude of different kinds.
有高空特技员 Aerial acrobats...
匿踪掠食动物 stealthy hunters...
以及世上速度最快的生物 and some of the fastest creatures on the planet.
非凡技能令它们超越地球的飞行始祖---昆虫 Their extraordinary skills enable them to surpass Earth original flyers---the insects.
但有一片广大的王国不在鸟类掌控范围---夜空 But there is a vast kingdom that the birds do not control---the night skies.
这片领域是由完全不同的生物统治 These are ruled by very different creatures, flying mammals.
会飞的哺乳动物蝙蝠 Bats.
在一个壮观的地点 And in one spectacular place these two populations,
分别称霸夜晚与白天的这两种族群，展开正面冲突 of the night and the day, collide.
征服天空 ~ Conquest Of The Skies ~
飞行赢家 TRIUMPH
这是西班牙中部的塞哥维亚 This is Segovia in central Spain.
这座峡谷的某些居民能让我们清楚看见 Some of the inhabitants of this gorge allow us to see very clearly
鸟类可以变成多才多艺的空中族群 how birds as a group have become so versatile in the air.
是因为它能够改变最基本的 Through the ability to change the shape and the size
飞行器官的形状和大小，那就是翅膀 of their basic flying mechanism, their wing.
这里就有一个绝佳的范例 And there is wonderful example of that just over here.
你或许以为鸟类在飞行时都差不多 You may think that birds are much the same when it comes to flight,
但事实上不同品种各有独特的飞行方式 but in fact different species need to fly in their own particularly way.
这只秃鹫就是空中腐食动物 This vulture is an airborne scavenger.
它以吃动物尸体维生 It feeds on the bodies of dead animals.
所以必须要能很快看见刚死的动物，赶在被抢走之前先占为己有 So, it need to spot any fresh carcass very quickly, and get to it before others claim it.
跟多数鸟类一样，它的视力绝佳 Like most birds, it has superb eyesight.
所以它会爬升到高空，持续扫视下方地面 So, it climb high in the sky, constantly scanning the ground below,
如有必要可以连飞几小时 for hours at a time if need be.
它演化出一种与众不同的翅膀，才能以这种高度特殊化的方式飞行 To fly in this highly specialize way, it is evolved a very distinctive kind of wing.
为了就近观察生活在这地区的众多秃鹫中之一种 To get up close to some of the many vultures that live in this area,
我来到保育人士固定喂食它们的地点 I visiting a place where they regularly fed by conservationists.
这些是高山兀鹫，体形最大的秃鹫之一 These are Griffon Vultures, one of the largest of all birds species,
每一只可重达11公斤 each one can weight up to 11 kilos.
要让11公斤的身体飞上天空需很多能量 Lifting a 11 kilo body high into the sky takes a lot of energy,
但是高山兀鹫不是只靠自己出力的 but the vultures don't supply that energy directly themselves.
通过观察它一天的行为得到关于它怎么做到这点的线索 A clue of how they do so comes from observing their behavior at the start of the day.
高山兀鹫在上面那些岩架上栖息和筑巢 Those vultures roost and nest on ledges up there.
它们不是早起的鸟儿 是因为它们要靠太阳起飞 They not early rises. That's because they rely on the sun to get airborne.
当气温开始升高，多块岩石反射太阳的热能 As tha day warms up, patches of bare rock reflect the heat of the sun,
形成一道道上升的称为热流的热空气 forming columns of rising hot air known as thermals.
高山兀鹫很清楚要怎么利用那些热流 And the vultures know exactly how to exploit those thermals,
花费最少的力气飞上高空 to be carry high in the sky with a minimum of effort.
它的翅膀在几百万年前就已定型 They have wings that have been shaped over millions of years
用来尽可能捕捉住上升热空气 to catch as much of that rising air as possible.
巨大的翅膀宽度惊人，翼展超过2米 They huge, very broad, with a span of over 2 meters.
但乘着热流飞行或许没有看起来那么容易 The riding thermals may not be as easy as it looks.
热流是一道狭长的上升空气 A thermal is quite a narrow column of rising air,
要留在里面，高山兀鹫必须做出急转弯 and to stay within it, a vulture has to make quite sharp turns.
但这可能造成悲剧 And that could lead to disaster.
急转弯时，靠内的翅膀前进的距离 In a tight spiral, a vulture inside wing
比靠外的翅膀短 travel a shorter distance than its outer wing.
如果测量靠内翅膀的速度 And if we were to measure the speed of this inner wing,
会发现它在空中前进的速度慢了很多 we will find that it moves much more slowly through the air.
这表示它制造的升力较小 This mean it generates less lift.
因为升力较小，高山兀鹫很容易会失速 So little in fact, that the vulture could easily stall and drop from the sky.
提示靠控制翼端羽毛的特殊能力避免憾事 It avoid that by having special control over the feathers at the ends of its wings.
那些羽毛可以一根根张开 They can be splayed so that they separate.
因此，每根羽毛都有如一片额外的小翅膀 As a result, each feather acts as a small extra wing,
可以制造足够的总升力 and together they increase overall lift.
让高山兀鹫顺利急转弯 This enable the vulture to turn in a tight circle,
就能留在热流里向上翱翔 and so hold its place in a thermal and soar upwards.
使用这种技能，高山兀鹫可以攀升到离地面1公里的高空 Using this technique, a vulture can climbe to a height of a kilometer
几乎完全不用拍翅 above the ground with scarcely of flap of its wings.
但接着，如果在下方发现食物 And then, if it spot food down below,
它就会改变飞行方式迅速下降 it can switch its flight technique and descend at speed.
它一落地就必须跟其他同伴争抢大餐 Once on the ground it has to compete with other vultures for the share of the feast.
现在那些宽大翅膀可以改用来打退对手 Now, those broad wings are useful to help muscle out it's rivals.
但这可能会伤及事关重大的翅膀 And that can put those all important wings at risk.
中空轻量的鸟骨通常也是很脆弱的 Bird bones being hollow and lightweight are also usually very fragile.
如果鸟的翅膀骨折就等于是被判死刑 And if a bird breaks it's wings that usually a death sentence,
因为多数小型鸟类几乎每天都得进食 because most small birds have to feed every day or so.
但这是秃鹫的翅骨 But this is the wingbone of the vulture
秃鹫体形庞大可以在胃里塞满食物 and vultures are so big and can fill their stomach so much food
所以可以2周甚至3周不进食 that they can go without a meal for two or even three weeks.
因此当凶恶易怒的秃鹫起了纷争 And as a concequence when these aggressive quarrelsome vultures have a row
甚至伤了彼此，它的断翅可以自行愈合 and perhaps injure one another, a broken wing can heal itself,
可以看到这根秃鹫的翅肌，断裂后又愈合起来了 and this is the wingbone of the vulture, as you can see, it has been broken and it has healed.
这根断骨的主人应该能撑到再次翱翔 It's owner may well have lived to soar again.
这种翱翔技能运用的不只是热流 This soaring tehnique can exploit not just a thermals
还有吹到山脊和山岳转向往上的风势 but also winds deflected upwards by ridges and hills.
其他大型鸟类也透过同样的翅膀形状帮自己翱翔 The same wing shape is used by other large birds to help them soar.
鹰 Eagles.
鹈鹕 Pelicans.
还有每年夏天长途跋涉飞来西班牙的一种鸟 And the bird that makes immense journey here to Spain every summer.
两只年轻小鹳 Two young storks.
它们的爸妈每年来到西班牙北方这座小镇 Their parents come here every year to this small town in northern Spain
远从非洲前来是为了交配筑巢和养育幼雏 in order to mate and nest and rear their young all the way from Africa.
有些甚至远从南端的好望角出发 它们能完成这趟长途飞行 Some from as far south as the Cape. And they make that immense journey
是通过寻找上升暖空气的热流 by finding a thermal of a column of rising air.
在里面盘旋，就这样爬升到高空 Circling in it, allowing it to carry them high in the sky,
然后滑翔到旅程的下一个段落 and then gliding off on the next stage of the journey
寻找另一道热流准备再次爬升 to find another thermal to take them back up again.
这是一种极为省力的旅行方式 It's an extraordinary energy efficient way of travelling.
所以宽大翅膀搭配分岔翼端让大型鸟类得以在空中翱翔 So broad wings and splade wingtips enabled larger birds to stay airborne.
但其他鸟类面临不同的飞行挑战而演化出不一样的专长 But other birds faced very different challenges and so evolved different specialities.
为了观察演化成世上最高明掠食者的一种鸟 To watch a bird that has evolved in to one of the worlds most skilful hunters,
我来到意大利罗马 I have comed to Italy and the city of Rome.
有一种鸟会飞越这些建筑的屋顶 There is a bird that fly over these roofs,
到处寻找猎物，但不在地上而在天上 that find its prey not on the ground, but in the air.
它的成功必须归功于它的速度 And it owe its success to its speed.
事实上，它被誉为世上动作最快的动物---游隼 In fact, it said to be the fastest moving animal on Earth---The Peregrine.
游隼猎食其他鸟类 Peregrines hunt other birds.
现在有很多品种的鸟住在城市里 Many different kinds of birds now live in cities,
被这里可以轻松找到的食物和庇护所吸引 attracted by the food and shelter that is so easily found here.
这种高楼建筑是掠食者瞭望觅食的最佳地点 And a tall building like this is an ideal lookout for a hunter.
猎物会从它们选定的任何方向飞来 Flying prey can move in any direction it chooses,
掠食者必须够快和够灵活才能饱餐一顿 so a hunter has to be both, fast and agile if it to get a meal.
游隼的翅膀形状很特殊 A peregrine wings have a very special shape.
这是翼端收尖的后掠翅膀 They pointed and swept back.
如果翼端是钝形，空气会在翼端后方旋转 If wings have a blunt end, air will swirl over that end,
形成多道乱流 forming trails of turbulents.
这些乱流就像煞车一样会让鸟的速度变慢 These act like brakes slowing a bird down.
但尖形翅膀的翼端缩小，就能减少乱流 But pointed wings had shrink that edge, and so reduce the turbulents.
朝向身体的后掠翅膀，让游隼变得更加流线形 Pulling the wings back towards the body, makes the bird even more streamlined.
速度是游隼成功的关键 And speed is crucial to a peregrine success.
它也有锐利视力可以看见远在一英里外的猎物 It also has acute vision that enable it to spot prey over a mile away.
对于在猎食的游隼来说，这些鸟是主要目标 And for the peregrine that hunt in Rome, these birds are prime targets.
椋鸟 Starlings.
它们速度也一样飞快 They too are fast flyers,
较小的体形让它们的动作更加灵活 and their smaller size make them even more maneuverable.
所以要抓住椋鸟，游隼的速度必须要快 So, to catch a starling a peregrine must be even faster,
为了进行加速和奇袭，游隼从上方进行攻击 and in order to gain speed and surprise, it attacks from above.
首先，它会爬升 First, it climbs.
当它选定一群目标猎物，就会转头... When it sees a group of its potential prey, it turns...
急降...然后拍翅加速 dives... and accelerate by beating its wings.
椋鸟还不知道危险正在逼近 The starlings are still unaware of the danger hurtling toward them.
最后游隼把翅膀往后收 这动作叫俯冲 Finally the peregrine draws its wings back. This is called the stoop,
这种超流线外形能够切穿空气 a superb streamline shape that slices through the air.
它现在的时速能达到200英里以上 Now, it can reach speed of over 200 miles an hour.
一旦接近目标，游隼就张开翅膀 As it neared its target, it open its wings
减缓下降速度然后展开最后扑击 to slow its descent and makes its final launch.
椋鸟为游隼提供了充足的食物来源 Starlings in fact, are an abundance source of food for the peregrines.
它们来到罗马过冬，被这里的温暖气候吸引特地前来栖息 They come into the city in the winter, attracted no doubt by the warmth in order to roost.
每天的黄昏，椋鸟开始飞来 Every evening at dusk, the starlings start to arrive,
为了抵挡游隼，它们采用一种令人瞩目的自卫方式 and they have a remarkable way of defending themselves against peregrines.
这得靠它们成群结队飞出紧密队形的能力 One that relies on their ability to fly together in tight formations as a flock.
它们来了，数量庞大，高达数万或数十万 And here they come, vast numbers of them, tens of thousands, hundreds of thousands.
这仿佛是一场巨大的黑色雹暴，有如鸟类暴风雪 It's like a great black hailstorm, a blizzard of birds.
现在有些椋鸟开始飞得更近，做出更加复杂的动作 And now, some start to fly closely together and perform far more complex maneuvers.
看看这一大群鸟是怎么聚集形成一团黑云，然后又转向散开 Look how these great flocks come together, form a cloud, veer away and split,
这是一段令人啧啧称奇的飞行舞蹈 It's a quite extraordinary piece of aerial navigation.
我们还是无法确认它们为何表演这种复杂群舞 We still unsure exactly why they perform these elaborate dances,
但通常起因都是有掠食者出现 but they often triggered by the arrival of a predator.
今天也不例外，因为在那边的一栋建筑物 And today is no exception, because over there,
我看到了一只游隼 on one of those buildings I have seeing a peregrine.
成群结队飞行这种行为，本身就是一种自卫机制 Coming in a great numbers like this, is in itself a defense,
因为如果你被数万只同类包围 because if you surrounded by tens of thousands of others,
游隼抓到你的机会就很小 well, it's a good chance that the peregrine won't get you.
但空中群舞只是一套更复杂自卫策略的一环 But the aerial ballet is part of a more complex defensive strategy.
当游隼收拢翅膀俯冲，展开攻击 When a peregrine does attack with its wings drawing back in its stoop,
以紧密队形飞行的椋鸟就开始协调逃跑策略 the starlings flying in their tight formation coordinate their escape.
它们没有四散惊飞，以免脱队落单者被抓住 Instead of scattering in different directions when a struggler might be picked off,
而是聚集一起，连做最陡的急转弯也没有散开 they stick together, even when they make the sharpest of turns.
分析罗马椋鸟群飞行路径的近期研究 Recent studies analyzing the flight birds of these Roman flocks,
已经揭露它们是如何做到这点 have now revealed how they manage to do this.
直到最近人们才开始了解椋鸟群飞是怎么达成 Just how they achieve this was not understood until very recently.
现在罗马大学的一组物理学家 But now a team of physicists from Sapientia University in Rome
开始着手寻找答案 is beginning to find the answers.
可以看到好几大群椋鸟就在我们前方飞舞 We see these huge flocks of birds dancing in front of us
每次看到它们都会想 and every time that you look at them you wonder,
这么多鸟是怎么做到行动如此整齐划一就似单一个体 how it is possible that so many birds would be as only one entity.
他们沿着屋顶放置一连串摄影机，俯瞰最受椋鸟欢迎的栖息地 They precisen series of cameras on a rooftop overlooking a favourite starling roostsite
就在罗马中央火车站旁 just outside Rome's main railway station.
这些摄影机以3D画面记录椋鸟群的复杂动作 The cameras record the flocks complex manouvers in three-dimensions.
接着用先进电脑软件以绝佳精准度 Advanced computer software then locks on to the flightpods of thousands of individuals,
锁定数千只椋鸟的飞行路径 with extraordinary precision.
他们煞费苦心的研究得出一个惊人的结果 Their painstaking work has produced a remarkable insight
揭露椋鸟协调彼此行为的方式 into how starlings coordinate their behaviour.
我们发现的主要结果是，每只鸟都会跟周围的7只鸟互动 The main result that we found is that each bird interacts with the seven birds around it.
不管这些鸟的距离远近都一样，这是让椋鸟群保持稳定的关键 Regardless of the distance between these birds it is the key to have a stable flock.
每只椋鸟都通过隐形网络，连接周围的7只同伴 And individual starling is affectively linked to seven around it by an invisible web,
就算它们之间距离越来越远也一样 even if they drift far apart.
这就是让椋鸟聚集成群的隐形联系 This is the hidden glue binding the flock together.
但这或许也能作为沟通频道 But it may also act as a communication channel.
转向躲避掠食者的一只椋鸟引发涟漪效应 A bird that turns to evade a predator triggers a ripple effect
迅速传遍重叠的网络 that passes rapidly through the overlapping networks,
让整个鸟群同时转向 causing the whole flock to turn as one.
特别的是，讯息在几毫秒内能传遍鸟群 Special thing is that the information can be passed through the flock in milliseconds
因此它们能够快速地躲开掠食者 and this allows them to escape very quickly from predators.
椋鸟群的自卫机制多半能让它们保住一命 Most of the time the starlings flock defence keeps them alive.
但它们偶尔还是招架不住游隼高速俯冲奇袭的攻势 But now and again the share spreed and surprise of peregrins diving attack prooves too strong.
在天上的数百万只椋鸟当中 Out of the millions of starlings in the skies
今晚只有少数几只会沦为游隼的猎物 only a few will fall pray to the peregrins tonight.
当夜色终于笼罩天空，椋鸟群突然降落 As the light finally fades, the flock suddenly descends into the trees
停在今晚要栖息过夜的树上 that will be their roost for the night.
游隼的锐利视力在晚上就变得无用武之地 The peregrines sharp eyesight doesn't operate nearly so well in the dark.
所以现在椋鸟群安全了...至少明天之前都安然无恙 So now, the starlings are safe... until tomorrow that is.
在6千英里外的南美 6,000 miles away in South America,
有另一种鸟拥有完全不同的技能 there are other birds with a very different skill.
它们也是靠翅膀觅食 And they also find their food on the wind.
在厄瓜多尔的云雾林，植物会源源不断制造一种食物 In the Cloud Forest of Ecuador there is a plentiful supply of a type of food
用来吸引飞行动物 produce by plants to attract flying animals.
花蜜 Nectar.
约在1亿3千万年前，植物用富含糖分的饮料作为贿赂收买昆虫 Around 130 million years ago, plants recruited insects to transport pollen
为它们在花朵之间传递花粉 from one flower to another by bribing them with a sugar rich drink.
刚演化出现的鸟类无法采集花蜜 Birds when they first evolved were unable to collect it,
因为附近通常不会有稳固的栖息处能让鸟落脚 because there where seldom something solid nearby, on which they could perch.
接着到了约3千万年前 Then, around 30 million years ago,
出现了不需要落脚栖息的一种鸟 a kind of bird appeared that had no need of such a perch.
蜂鸟 Hummingbirds.
它们可以悬空停留 They could hover.
它们是靠飞速拍翅做到这点 They do so by beating their wings extremely swiftly,
拍翅速度快到会发现嗡嗡声 so fast in fact, that they make a humming noise.
最大的蜂鸟每秒约拍翅14下 The largest hummingbird beat its wings around 14 times a second,
但有些小型品种每秒能拍80下 but some tiny species are able to do so 80 times a second.
要以这种非凡的方式飞行，蜂鸟必须改变 To fly in this extraordinary way, hummingbirds have changed
翅膀的结构以及拍翅的方法 the structure of their wings and the way they beat them.
科学家道格.奥修勒在厄瓜多尔 Here in Ecuador, scientist Doug Altshuler
分析它们究竟是怎么做到的 is working to analyse exactly how they do so.
蜂鸟是很了不起的动物，它们在生理和身体结构极其恰当 Hummingbirds are remarkable animals, they have extreme adaptations in physiology and anatomy,
也很有独特的行为，它们能够悬空 and they also have a very unique behavior, they can hover,
我们采取的途径是研究 and the approach that we have taken is to study how those
这些生理和身体构造对它们的悬空能力有什么影响 physiological and anatomical adaptations determine their hovering ability.
他以高速摄影机详尽无遗地记录蜂鸟飞行机制 Using High-Speed cameras, he record the mechanics of their flight in minute detail.
用40倍慢动作重播画面 He can slowdown the action by around 40 times,
因此能仔细观察完整动作 and so observe exactly what's taking place.
多数鸟都是上下拍翅 Most birds flap their wings up and down,
但蜂鸟的拍翅动作比较像昆虫 but hummingbirds flap theirs more like insects.
它们会在每次拍翅之间扭转翅膀 They twist their wings around between strokes,
所以前后拍打翅膀时都能制造升力 and so can generate lift when flapping both forwards and backwards.
高速进行这动作会对翅膀造成巨大压力 Doing this at high speed put a huge straying on their wings.
为了承受这压力，蜂鸟的翅膀有很特别的结构 So, to withstand it, the wings have a special structure.
蜂鸟的翅膀很僵硬，急速前后拍动的时候 The hummingbird wing is very stiff, and undergo a few changes in shape
形状很少有变化 as it rapidly beats back and forth.
这种僵硬翅膀是来自变形的骨头 They owe this stiffness to a modification of the bones.
它们的臂骨已经缩小，但掌骨被拉长 The arm bones have shrunk, but the bones of the hand
负责支撑大半的翅膀表面 have elongated and support most of the wing surface.
在肩膀和腕部扭转僵硬翅膀 Twisting this wing of the shoulder and at the wrist
就是蜂鸟有拍翅动作的由来 produces the hummingbird distinctive wing beat.
道格也要调查蜂鸟飞行的另一个大谜题 Doug is also investigating one of the great mysteries of hummingbird flight.
那就是它们的悬空侧飞能力 Their ability to move sideways in mid-hover.
蜂鸟可以跟着在风中前后摇晃的花朵移动 Hummingbirds are able to track flowers that are moving back and forth in the wind,
我一直想深入了解这一点 and this was something I always wanted to know more about.
为了复制花朵的摇晃 To replicate the swaying motion of a flower,
道格在一条机械滑轨上放了一盒花蜜 Doug places a reservoir of nectar on a mechanical slider.
不久，就有一名自愿者出现 Befor long, he has a volunteer.
神奇的是，这只蜂鸟跟随移动顺利跟上滑轨动作，还能喝到花蜜 Amazingly, it manages to track sideways to keep-up with the slider, and still feed.
蜂鸟是运用拍翅动作的一个意外特征 The bird is exploiting an unexpected feature of its wing beat,
不是拍打翅膀，而是在每次拍翅结束时扭转翅膀 not the flapping itself, but the twists at the end of each stroke.
当它们悬空飞行，翅膀往前拍时会对称扭转 During hovering flight, as the wings come forward,
所以力道能够维持平衡 they rotate symmetrically, so the froces remain in balance,
但如果扭转出现差异，例如一片翅膀比另一片更快扭转 but if they instead rotate differently, so that one wing rotate before the other,
力道就不再平衡 then the forces are no longer in balance,
这种不平衡就足以把蜂鸟往两侧推动 and this asymmetry can be sufficient to push them to one side of the other.
变形翅骨搭配精准控制的翅膀动作 So, a combination of modified wing bones, and precise control of wing motion,
让蜂鸟拥有采集花蜜所需的灵活飞行能力 gives hummingbirds the aerial agility they need to collect nectar.
而且它们需要大量花蜜，悬空会耗费大量能量 And they need plenty of it, hovering burns a huge amount of fuel.
所有蜂鸟都必须持续吸食高热量花蜜饱腹 All hummingbirds have to constantly top at their tacks with high energy nectar.
花蜜不足时，竞争会变得很激烈 And when supply are low, competition can be fierce.
现在它们把飞行技能用在完全不同的事情上 Now, their flying skills are put to a very different use.
那就是击退对手 To fight off rivals.
各种鸟类的翅膀都经过适应，能以高度特殊化的方式飞行 So, different birds adapted their wings to fly in highly specialise ways.
有些鸟开始猎食地球的飞行始祖昆虫 Some began to hunt the Earth first flyers, the insects,
在这场战争中，双方高下立判 and in that battle,there is now no real contest.
但因为多数鸟类的成功 But because most birds rely for so much of their success
最大功臣都是绝佳视力，有个让大部分鸟类却步的重要环境 on their exceptional eyesight, there is one major habitat that is largely close to them,
不是地点，是时间 not a place, but a time,
那是夜晚 the night.
在英国的乡村地区，有一种鸟可以在黑暗中飞行 In the British countryside however, there is a bird that can fly in the dark.
仓鸮，它最爱的美食之一是田鼠 The Barn Owl and one of its favorite meals is a Field Mouse.
但首先，它得在黑暗中找到猎物 But first, it has to find it in the dark.
老鼠对靠近的掠食者极为警戒 A mouse is extremely alert to the approach of a predator.
但仓鸮有已经完成匿踪演化的翅膀 But the Barn owl has wings specially adapted for stealth,
还有能透视黑暗的感官 and senses that can penetrate darkness.
它的眼睛对微弱光线很敏感，但就算田鼠躲在看不见的地方 Its eyes are very sensitive in low light, but even if the mouse is out of sight,
它仍是不安全，仓鸮的听觉也很敏锐 it's still not safe, the owl's hearing is also very acute.
它脸上的两个碟状环圈能把声音导引到它的两个耳朵 Those two disks on its face channel sound into its two ears,
它的耳朵在头部的位置，高度稍有不同 which are on a slightly different level on the head,
这个差异能让仓鸮锁定声音来源 and that difference enables the bird to pinpoint the source of the sound,
不论是在空中，或者是在地面 whether it's in the air, or down on the ground.
但为了听到那些微弱声音，它的拍翅必须非常安静 But in order to hear that sound, its wing beats have to be very very quiet,
等它去猎食，我们就能看出来它是怎么做到的 and the way to achieve that, we can see when it go hunting.
它能安静无声飞行的主要原因在于它的翅羽性质 The key reason for it silent flight lies in the nature of its wing feathers.
它的翅膀后缘的羽毛外围分散错落 Along the back edge, their fringe is frayed and tatty.
多数鸟的翅膀边缘坚硬 Most birds wings have a hard edge,
这会制造很大的声响 and this can cause quite a loud noise.
声响来自流过翅膀上方的空气摩擦翅膀表面形成的乱流 The source is turbulents produce when air flowing over the wing rub against its surface.
当这股乱流接触坚硬的翅膀后缘 When this swirling air meet a hard back edge,
高度的落差会扩大声响 the sudden drop-off hugely amplifies the noise.
但仓鸮的杂乱羽毛可以避免这现象，透过较柔软的边缘 But the Barn Owl tatty feathers avoid that, by creating a softer edge,
为乱流制造缓冲因此能降低声响 they cushion the turbulent air and so reduce noise.
所以无声飞行能让仓鸮听见猎物 So, silent flight allow the owl to hear its prey,
然后悄悄逼近 and conceal its approach.
但要进入猎杀位置它必须飞得极慢 But to position itself for the kill it need to fly extremely slowly,
它是靠特别宽大的翅膀做到这点 and to achieve that it has particularly broad wings.
这种缓慢无声的飞行让田鼠几乎毫无逃脱机会 This slow silent approach leaves a field mouse little chance of escape.
在云层厚重或没有月亮的夜晚 On nights, when there is thick clouds or no moon,
连仓鸮的锐利视力都派不上用场 even an owl sensitive eyes struggle.
但有些生物具有高度特殊化的感官 But there are creatures that have such highly specialise senses
能让它们在一片漆黑里飞行 that they able to navigate in total darkness.
在昆虫界，有些蛾类拥有精细触角 Among insects, there are some moths who their elaborate antenna
能侦测一食物或配偶的气味 are able to pick-up the scent of food or a mate.
还有一种夜行性动物 And there are those nocturnal animals,
也就是最后演化出现的飞行生物－－蝙蝠 the last group of flying creatures to appear on Earth－－the bats.
为了解它们怎么跟昆虫争夺夜空的主导权 To see how they battle with the insects for dominate of the night skies,
我们要前往婆罗洲雨林 we heading into the rainforests of Borneo.
很多蝙蝠不是靠视觉或嗅觉觅食 Many bats find their food not by sight or smell,
而是用一种完全不同的高度进化导航系统 but by using a very different and highly advance guiding system.
要找蝙蝠的方法之一，是寻找它们的理想巢穴 One way to find them, is to search for their ideal home,
例如我的下方那座深邃漆黑的洞穴 a place like that deep black cave beneath me.
如果你整晚都在飞行，像那样的洞穴 If you fly at night, there is no better place to spend the day
就是白天休息的最佳地点 than in a cave like that.
这是哥曼东洞穴 This is Gomantong.
这个洞穴是由地下隧道和巨大洞室组成的庞然网路 The cave is a vast network of underground tunnels and cathedrals size cabins.
由历经数百万年的流水侵蚀凿穿而成 It was carve out by streams of water over millions of years.
现在这里成为各种穴居动物入住的大规模社区 And now, it's home to a remarkable community of cave dwelling specialists.
为了找到我要寻找的生物，绞车把我拉上洞顶 To find the creatures I'm looking for, I'm been winch high up towards the ceiling,
这些高耸壁面是飞行动物的理想栖息处 where the towering walls make ideal roost sites for flying animals.
从我身边飞过的这些小鸟是雨燕 These little birds fly pass me are Swiftlets
它们在洞穴壁面筑巢 that have made their nests on the walls of the cave.
雨燕是在白天活动，离开洞穴去猎食昆虫 They are active during the day, and they leave the cave to hunt insects.
我想找的蝙蝠在后方，半明半暗的更深处 The bats, that are I'm interesting in, are further behind me in the semidarkness,
现在是白天，它们正在熟睡 and there are sleep now, during the day.
蝙蝠的体形还不到老鼠的大小 The bats are scarcely the size of mice,
它们的翅膀是由很长的手指形成 their wings are constructed with very long fingers,
而且是用脚抓着岩石倒挂 and they hang by their feet from the rock.
虽然后面那里有几只蝙蝠 Although there are few of the bats there,
但在这洞穴深处住有数量庞大的蝙蝠群 deeper in this cave they exist in huge numbers.
为了找到它们的栖息处，我们要继续深入哥曼东洞穴 To find their roosts we heading still deeper into Gomantong cave.
在我上方高处的岩石洞穴洞顶，隐藏在黑暗中 High on the rocky cave ceiling above me, hidden in the darkness,
有数量惊人的蝙蝠 there are vast numbers of bats.
你可以知道这些蝙蝠一定数量众多 You can get some idea of how many there must be,
因为我身后这一大座丘状物，是由蝙蝠粪便堆积而成 because of this huge dune behind me, that form of their droppings,
在表面可以看到不断移动的小亮点 and if you see little moving glimpse on the surface,
那是一大群蟑螂在蝙蝠粪便堆里啃咬乱钻 that comes from an army of cockroachs which are chewing their way
不浪费最后一滴的养份 through the bats droppings to extract the last particles of nutriment.
有人认为这一座洞穴上面有100万只蝙蝠 Some pepole think there are a million bats up here in this cave.
在黑暗之中看不见它们 It's impossible to see them in the gloom,
但特殊夜视摄影机能让它们露面 but special night vision cameras can reveal them,
它们成群聚集倒挂在洞顶 densely pack crowds hanging form the ceiling.
它们的小眼睛已经适应微弱光线，但还是无法看穿黑暗 Their tiny eyes are adapted to low light, but they cannot penetrate the blackness.
然而在数百万年前 Millions of years ago however, these bats evolve
这些蝙蝠演化出一种非凡的导航系统，那就是回音定位或叫声纳 an extraordinary guiding system known as echolocation or sonar.
蝙蝠能在喉咙发出音调极高的声音，然后往前发射 A bat produces extremely hyper sounds in its throat, and then project them forward.
我们已经把这声音放慢 We have slow the sounds down, but can still only hear them
但还是要转换成较低频率才能听见 by converting them to lower frequencies.
这种声音从墙壁反弹变成回音，然后被蝙蝠的大耳朵接收 They bounce of the walls as echoes and are detected by the bat huge ears.
蝙蝠持续进行回音定位 These are in constant movement and enable the bat
因此能够极精准地得知周遭环境 to map its surroundings with remarkable precision.
但这些蝙蝠不只需要在黑暗中飞行 But these bats not only need to find their way in the dark,
还必须要能觅食 they also need to find their food.
目标是夜行性飞虫 Night flying insects.
这其中包括蛾类 And among them are moths.
锁定这些移动目标 Locking-on to these moving targets is a supreme test
是蝙蝠回音定位系统的最大挑战 for the bats echolocation system.
在锁定目标之后，它声纳转换成攻击模式 As one homes in, its sonar beam switches into attack mode,
提高声音发射次数 increasing the rate of its pulses.
这能让它精准定位猎物 This enables it to precisely pinpoint the location of its prey.
但在夜空大战中蝙蝠并非百战百胜 But in the battle of the nightskies the bats don't have it all in their own way.
一组科学家在婆罗洲研究蝙蝠跟猎物互动的方式 A team of scientists in Borneo is studing the way bats interact with their pray.
首先，他们设陷阱抓蝙蝠 First, they catch the bat into the trap
用细铁丝让蝙蝠转向进入下面的袋子 that uses thin wires to divert to main in the pouch below.
它在这 －好 There it is. - Nice.
很漂亮 Ye this is gorgeous.
蝙蝠和蛾已经共同演化了近6千万年 Bats and moths have could evolved for almost 60 million years
我们在这里立起大帐篷和安装这些摄影机 and so what we doing here with this giant tent and all these cameras
是想确认这场古老大战的实际状况 is to trying figure out what's happening in this ancient battle.
还有了解蛾类如何躲过蝙蝠攻击并幸存 Trying to understand how moths survive a bat attack.
都准备好了吗？ －可以开始了 －很好 Everything set up here? - Yes, everything ready to go. - Awesome.
这帐篷是作为控制飞行场 This tent acts as an controlled flight arena,
所有动作和声音都会被详尽无遗地记录下来 in which every movement and sound can be recorded in minute detail.
用多部3D摄影机和超音波麦克风拍摄这些互动 Filming these interactions with multiple cameras in 3-D and ultrasonic microphones,
就能看见和听见它们的互动过程 we can see how these interaction unfold, and hear how they unfold.
这些研究揭露蛾类不一定总是逃不过蝙蝠的攻击 These studies have revealed that moths do not always fall prey to the bat attacks.
我们知道有很多蛾类有能侦测蝙蝠的耳朵 We know that many moths have bat detecting ears
它们能听见蝙蝠靠近，听到蝙蝠做回音定位的叫声 they can hear the bats coming, they hear their echolocation cries
接着就会从空中降落，停止飞行 and dive out of the sky stop flying.
抓住了？ －拿去 You got it? - There you go.
全他们的研究发现有一种蛾拥有完全不同的自卫策略 But the teams works identified a moth, with very different defence strategy.
对这种蛾播放蝙蝠叫声的录音揭露了一种惊人能力 Playing recordings of a bat sounds to this moth reveals a remarkable ability.
最近我们在婆罗洲发现 Here in Borneo, we recently discover that Hawk Moths
天蛾会自己发声应对回音定位的叫声 respond to these echolocation cries with their own sounds.
标记和计算方向 Called lock-in sound protection.
天蛾是用腹部尾端的变形生殖器发声 Hawk Moths do with the tip of their abdomen with modified genitals,
它们用生殖器摩擦腹部的内侧 they rub the genitals against the inside of the abdomen,
作为蝙蝠攻击的应对措施 and reply to this bat attack.
被绑住的天蛾只能在拍摄和收音范围内活动 The moth is tether to keep it in range of the cameras and microphones,
接着蝙蝠被放出来 then a bat is released.
靠近天蛾时，蝙蝠的声纳脉冲转换成攻击模式 As the bat approaches the moth, its sonar pulse switches to attack mode,
但天蛾在这时做出应对 but now the Hawk Moth responds,
它发出自己的刺耳声响得到一个惊人的成果 sending its own rasping sound back with astonishing effect.
到了最后一刻，蝙蝠似乎找不到天蛾，所以无法抓住它 At the last moment, the bat appears to lose track of the moth, and fails to catch it.
这显示天蛾发出的声音会干扰蝙蝠的声纳 We have shown that these moth sounds actually jam the bat sonar,
它们会扰乱从昆虫反弹的回音 they interfere with the returning echoes from the insect,
让蝙蝠无法定位天蛾 and causes the bat to miss the moth.
团队发现，在争夺夜空的持续战争中 The team has discovered that insects are fighting back
昆虫会展开反击 in the ongoing battle for the night skies.
但当然还有很多其他飞虫没有这种自卫机制 But there are, of course, plenty of other flying insects with no such defenses.
而且在哥曼东洞穴的森林就住有大量昆虫 and they live in vast numbers in the forest outside Gomantong cave.
所以在每天傍晚的黄昏时分 So, every evening as dusk arrive,
蝙蝠就会离开安全的隐秘家园去猎食 the bats leave the safety of their secluded home to hunt.
现在，蝙蝠开始使用回音定位技能 And now, the bats are been in use their echolocation skill
飞出位于洞穴深处的栖息处 to fly out from their roosts in the depths of the cave,
来到靠近洞顶的位置冲出这个小出口 coming close to the ceiling and then wheezing out through this little entrance here.
它们不会撞上洞顶或彼此 They don't collide with the roof, they don't collide with one another,
也不会撞到我，这完全是靠回音定位做到的 它们飞走了！ or even with me, all to that echolocation. There they go!
但这只是其中的极少数 But this is just a trickle, the main exodus
大多数蝙蝠是从位于洞穴更深处的一条通道离开 is taking place up a chimney that's deeper in the cave.
为了就近观察百万只蝙蝠集体出洞的方式 To watch close-up the way the bats achieve their million strong mass departure,
我被绞车拉上200米进入一条漏斗型通道，这被蝙蝠作为山洞的主要出口 I'm being hold-up 200 feet into the tunnel which serves as one of the cave main exits.
通道顶端有一个大洞 At the top, there is a gaping hole.
现在蝙蝠准备要离开了 And now the bats are preparing to leave.
它们聚集在靠近出口的一个较小洞室 They have assemble in a relatively small chamber close to the exit,
不断绕圈飞行，形成一大团旋转黑云 and are flying round and round in a great swirling crowd,
等待天色变暗 waiting dor day light to fade.
现在它们出洞了 And now, off they go.
这段短暂的黄昏时分是日行和夜行飞行动物 This refire of dusk is the moment when the two communities,
这两大族群可能在空中相遇的时间 the day flyers and the night flyers may encounter one another in the air.
危险在外面等候 Outside danger awaits,
跟它们共享天空的 hunters belonging to that other great group of animals
另一种伟大动物...鸟类 with which their shares the skies... birds.
雕，鹰和鸢 Hawks, Eagles and Kites.
就是因为它们迟迟不愿离开山洞 They are why the bats were reluctant to leave,
拖到现在才一举倾巢而出，因为成群结队比较安全 and why they now do so in one continuous torrent, there is safety in numbers.
但还是有些蝙蝠得付出代价 But some will pay the price.
当然绝大多数蝙蝠都安全飞上森林冠层 The vast majority, of course, make it out over the forest canopy,
它们可以在那里使用回音定位技能觅食 and there they can use that skill of echolocation to find food.
不同动物移居天空的方式 The way that different animals have colonise the skies
绝对是自然界最伟大的传奇故事之一 is surely one of the most remarkable stories in the natural world.
昆虫率先在3亿2千万年前飞上天空 First to do so, over 320 million years ago, were the insects.
之后约1亿年间它们都没有竞争者 They had no competition for about 100 million years.
但接着有更大的飞行动物出现在空中－－爬虫类，翼龙 But then, much larger flying animals took in the air－－Reptiles. The pterosaurs.
然后又过了7千万年，恐龙的一个分支开始长出羽毛 Around 70 million years later still, one branch of the dinosaurs acquired feathers,
让这些动物得以展翅起飞 and that enable their owners to get airborne.
鸟类就此出现在世上 The birds had arrived.
最后约在6000万年前 And last in, about 60 million years ago,
开始有哺乳动物进占夜空－－蝙蝠 the night skies where invaded by mammals－－the bats.
在哥曼东洞穴这里，现有的三大飞行生物 And here, in Gomantong cave, the three surviving groups of flyers,
昆虫，鸟类和蝙蝠，仍然在持续进行的演化斗争中激烈交战 insects, birds and bats, are still lock together in an ongoing evolutionary struggle.
这场从3亿多年前 So, the battle for the supremacy of the skies,
展开的天空争霸战 that started over 300 million years ago,
每天都在全球各地继续上演 still continues every day around the world.