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in the Galapagos Islands during certain times of the year
一年中的某些时段，在加拉巴哥群岛上
large aggregations of scalloped hammerheads come together to circle around Darwin Island
成群的双髻鲨聚集在达尔文岛周围
scalloped hammerheads normally live in the open ocean, but here at Darwin Island they come close to shore in large numbers
双髻鲨通常生活在广阔的海洋之中，但大批双髻鲨涌入达尔文岛海岸
considering the vast numbers of fish here, it would be logical to assume that the Sharks come to feed, yet nobody has ever witnessed the sharks feeding
考虑到这里鱼的数量如此之多，我们有理由认为鲨鱼是来捕食的，但从来没有人见过鲨鱼觅食
instead, they just seemed to be swimming slowly by the reef
相反，他们似乎只是在礁石旁慢慢游动
what are these sharks up to, I'm hoping to find out I've come all the way to the Galapagos Islands to investigate these strange and mysterious sharks
这些鲨鱼在做什么，我希望能找到答案，我专程来加拉帕戈斯群岛调查这些奇怪而神秘的鲨鱼
I'm Jonathan bird and welcome to my world
我是乔纳森·伯德，欢迎来到我的世界
the Galapagos Islands are a remote archipelago 600 miles off the coast of Ecuador in the Pacific Ocean
加拉帕戈斯群岛属于太平洋厄瓜多尔海岸600英里外的一个偏远群岛
many incredible animals live here both above and below the water
许多稀奇动物都生活在海上和海下
it's famous for the largest fish on earth, the whale shark which inhabits these waters
群岛因为生活着地球上体积最大的鱼——鲸鲨而得名，
but divers also flock here to see hammerheads and lots of them
潜水员也聚集在这看成群的双髻鲨
hammerheads are the most common at the northern island of Darwin, famous for its stone arch
双髻鲨在达尔文岛北部最为常见，该岛以石拱而闻名
rolling into the water, my assistant Gator and I head down to the reef to wait for the Sharks
我和我的助手一起下水前往珊瑚礁等待鲨鱼
soon a huge school is swimming by my lens, hammerheads are of course known for their strange flattened heads
很快镜头前聚集了鱼群，双髻鲨无疑以奇怪的扁平头部而出名
but you have to wonder what is that flathead for
但你一定会好奇扁头是干嘛的
shark biologists put their own heads together to figure it out
鲨鱼生物学家们集思广益，试图找到问题的答案
at first they speculated that it gave the Hammerhead wider stereoscopic vision
起初，他们推测扁平头部为双髻鲨提供更为广阔的立体视野
but that didn't work, hammerhead eyes face in opposite directions
但此说法并不成立，双髻鲨的眼睛与视力方向相反
meaning they can't see in stereo, the wide head probably has nothing to do with eyesight
也就是说，他们在立体视觉上看不见东西，宽额头很可能与视力无关
so maybe it has to do with the sense of smell
与嗅觉有关
wider spaced olfactory organs would help the hungry sharks sniff out prey more accurately
宽度较大的嗅觉器官能帮助饥饿的鲨鱼更准确地嗅到猎物
well not really, although the nostrils and olfactory organs are widely spaced, a groove along the front of the head effectively connects them together
事实并非如此，虽然鼻孔和嗅觉器官的间距很大，但是沿着头部前方的压线可以有效地将鼻孔和嗅觉器官连接在一起
therefore they don't give the Hammerhead a better sense of directional smell than any other shark
因此，和其它鲨鱼相比，扁平的头部并没有给予双髻鲨更好的嗅觉定位能力
scientists finally hit upon a graceful reason for the awkward head
科学家们终于为双髻鲨宽阔的头部找到一个好的理由
it helps the Hammerhead turn faster by eliminating the need for large pectoral fins
消除双髻鲨对巨大胸鳍的需求，可以帮助其更快地转动
some sharks like the whitetip reef shark can rest all day if they want just gulping water to ventilate their gills
如果某些鲨鱼，比如白鳍鲨，想要给鱼鳃通气的话，可以休息一整天
the shark equivalent of breathing
鲨鱼休息的时候等于在呼吸
hammerheads on the other hand cannot accomplish this
另一方面，双髻鲨也无法做到的一点是
like most pelagic sharks they must keep swimming
像大多数中上层鲨鱼一样，双髻鲨必须继续游动
not only to stay up off the bottom but to breathe
不仅要从海底站起，还要呼吸
in an ironic twist of fate if a hammerheads stop swimming, it will drown
具有讽刺命运的是，如果双髻鲨停止泅水就会被淹死
the big flathead is a wing to keep the hammerhead up off the bottom
硕大的平头相当于翅膀，帮助双髻鲨离开海底
