SSS 2011-02-24
时间：2018-12-24 作者：英语课 分类：Scientific American(二)月
If you splashed down in the Atlantic, you'd flounder on which way to swim. But a hatchling loggerhead turtle would know just where to paddle—by reading the Earth's magnetic field. Scientists knew turtles can pinpoint 1 latitude 2 this way, because the field varies a lot from north to south. But not east to west. So how do turtles know which side of the Atlantic they're on?
To find out, researchers strapped 3 hatchlings into custom Lycra bathing suits, tethered to a tracking unit. They plopped each turtle into a small pool surrounded by magnetic coils. And they replicated 4 the magnetic fields of Puerto Rico and the Cape 5 Verde Islands, two points along the turtles' migration 6, with equal latitudes 7 but different longitudes 8. The hatchlings swam opposite directions in the two trials—both being the right ones, to stay on the migratory 9 track. The study appears in the journal Current Biology.
The researchers say turtles may calibrate 10 their migratory maps by sensing the magnetic field's intensity 11, and its inclination 12 to the Earth's surface—a combo that gives each point of the migration a unique signature. As for any human navigators out there, you'll just have to shell out for a GPS.
- It is difficult to pinpoint when water problems of the modern age began.很难准确地指出，现代用水的问题是什么时候出现的。
- I could pinpoint his precise location on a map.我能在地图上指明他的准确位置。
- The latitude of the island is 20 degrees south.该岛的纬度是南纬20度。
- The two cities are at approximately the same latitude.这两个城市差不多位于同一纬度上。
- Make sure that the child is strapped tightly into the buggy. 一定要把孩子牢牢地拴在婴儿车上。 来自《简明英汉词典》
- The soldiers' great coats were strapped on their packs. 战士们的厚大衣扎捆在背包上。 来自《简明英汉词典》
- Later outplant the seedlings in a replicated permanent test plantation. 以后苗木出圃栽植成重复的永久性试验林。
- The phage has replicated and the donor cells have lysed. 噬菌体已复制和给体细胞已发生裂解。
- I long for a trip to the Cape of Good Hope.我渴望到好望角去旅行。
- She was wearing a cape over her dress.她在外套上披着一件披肩。
- Swallows begin their migration south in autumn.燕子在秋季开始向南方迁移。
- He described the vernal migration of birds in detail.他详细地描述了鸟的春季移居。
- Latitudes are the lines that go from east to west. 纬线是从东到西的线。
- It was the brief Indian Summer of the high latitudes. 这是高纬度地方的那种短暂的晚秋。
- Nothing makes earth seem so to have friends at a distance; they make latitudes and longitudes. 没有什么比得上有朋在远方更使地球显得如此巨大，他们构成了纬度和经度。
- Many migratory birds visit this lake annually.许多候鸟每年到这个湖上作短期逗留。
- This does not negate the idea of migratory aptitude.这并没有否定迁移能力这一概念。
- Pesticide levels in food are simply too difficult to calibrate.食品中杀虫剂的含量很难精确测定。
- I didn't realize the intensity of people's feelings on this issue.我没有意识到这一问题能引起群情激奋。
- The strike is growing in intensity.罢工日益加剧。
- She greeted us with a slight inclination of the head.她微微点头向我们致意。
- I did not feel the slightest inclination to hurry.我没有丝毫着急的意思。