2021-08-04海豹

视频：https://www.bilibili.com/video/BV12y4y167AG

Cutting out（裁剪） the middle man（中间人/中间商、一般用middleman）：标题意为 绕过中间商

Sieve（筛子）-toothed（有...齿的） seals may be whales（鲸鱼） in the making（在生产过程中）

Lake baikal（贝加尔湖）, near Russia’s border with Mongolia, is, by volume（量，储水量）, the biggest body of（大量） fresh water on Earth. At 1.6km, it is also the deepest. Several unusual animals call it home（把...当家）, including the world’s only species of freshwater seal.

Baikal’sseals are abundant. There are about 100,000 of them. But the lake is nutrient-poor, so how they do so well has been a mystery. A study just published in the Proceedings of the National Academy of Sciences, by WatanabeYuuki of the National Institute of Polar Research, in Tokyo, suggests the answer is by filtering（过滤） tiny organisms from the water.

filter-feeder n. 滤食性动物

Most seals eat fish. And Baikal seals do, indeed, have needle-pointed（像针尖一样尖的） canines（犬齿，犬科动物） of the sort expected of piscivores（食鱼动物）. But in 1982 researchers noted（特别指出） that they sport（穿戴某种有特色的东西） a second sort of specialised tooth behind those canines. These have frilled（带褶的） cusps（牙尖） which resemble（像） combs. At the time, nobody knew what to make of them. But Dr Watanabe speculated（猜测） that they might be an adaptation for feeding on other strange creatures dwelling in the lake.

piscivores =pisci（鱼）+vore（吃） 例：carnivore 食肉动物

herbivore食草动物

frill：裙褶

make sth. of sb/sth.领会、理解

feed on：以...为食/ 因...壮大、滋生（贬义）

Seals arrived in Baikal 2m years ago, from the Arctic Ocean. So too did some much smaller marine creatures, known as amphipods（端足类）. These have diversified into more than 340 indigenous（土生土长的） species. One of them, Macrohectopus branickii（某种虾）, spends its days hiding in the depths（深处） of the lake and then forages（觅食） in the shallows（浅滩） at nightin great numbers.

Marinemammals the size of seals would normally see amphipods as too small to hunt.But Dr Watanabe wondered if the Baikal seals’ comb like teeth might have evolved to enable them to rake（n.钉耙 v.仔细搜寻） these tiny crustaceans（甲壳纲动物） from the water in sufficient quantities to make them useful prey—much as some whales collect krill（磷虾） using comblike structures called baleen plates（鲸须板）. He and his colleagues therefore attached waterproof video cameras and accelerometers（加速度计） to a few seals, to monitor what they were getting up to. This equipment remained attached to the animals for between two and four days, before coming（变得） loose（come loose=undone松） and floating to the lake’s surface, whence（adv.从哪儿、从何处） the researchers were able to recover（=retrieve找回、找到） it.

get up to sth. 干，做（令人意外的事）

Footage from the cameras and data from the accelerometers showed that the seals were indeed pursuing the dense amphipod aggregations（群体） that form at night. They would dive in with their mouths open and collect prey before making another pass. Dr Watanabe estimates that each seal captures an average of 57 amphipods per dive—and thus thousands of them a day. The needle like canines are not redundant（多余的）, for the seals do hunt fish as well. But they also compete with those fish for the amphipods, thus partially bypassing（bypass 绕过） a link in the food chain and perhaps there by maintaining themselves in larger numbers than would otherwise be possible.

aggregate v.聚集

make a pass 追求

redundancy n.多余

Whether,were some of these filter-feeding（滤食的） seals to make it back to the ocean, they would follow the baleen-whale path and evolve into giants（巨兽）, is an interesting speculation（揣测）. But even confined to their lake, Baikal seals provide an intriguing（有趣的） example of parallel evolution（）.

be confined to 局限于...