时间:2018-12-24 作者:英语课 分类:Scientific American(三)月


英语课

This is Scientific American's 60-Seconds Science. I'm Karen Hopkin. This will just take a minute.


 


Elephants. They’re the SUVs of the animal kingdom. They’re big and rugged 1, and can carry lots of cargo 2. And now a study in the Proceedings 3 of the National Academy of Sciences suggests they come equipped with the quadruped version of all-wheel drive.


When it comes to locomotion 4, elephants are not exactly fleet of foot. And they seem to hold their legs straighter than other animals do, at least when they walk. So scientists set out to examine more closely how elephant limbs mechanically move all that mass around.


Six Asian elephants walked or ran over a sidewalk equipped with pressure sensors 5, as the scientists used high-speed video cameras to monitor their gait. And they found that elephant legs actually do bend enough to provide significant leverage 6 when on the move. More surprising is that pachyderms’ front and rear legs are on equal footing when it comes to acceleration 7 and braking. All other four-legged animals, like dogs or cats or horses, divvy up those duties. With their rear legs powering the push forward, and their front legs acting 8 as brakes.


That arrangement lets elephants trade speed for stability. Sadly, it does nothing for their fuel economy. Of course, they do have the roomiest trunk.


 


Thanks for the minute for Scientific American's 60-Seconds Science. I'm Karen Hopkin.

 



1 rugged
adj.高低不平的,粗糙的,粗壮的,强健的
  • Football players must be rugged.足球运动员必须健壮。
  • The Rocky Mountains have rugged mountains and roads.落基山脉有崇山峻岭和崎岖不平的道路。
2 cargo
n.(一只船或一架飞机运载的)货物
  • The ship has a cargo of about 200 ton.这条船大约有200吨的货物。
  • A lot of people discharged the cargo from a ship.许多人从船上卸下货物。
3 proceedings
n.进程,过程,议程;诉讼(程序);公报
  • He was released on bail pending committal proceedings. 他交保获释正在候审。
  • to initiate legal proceedings against sb 对某人提起诉讼
4 locomotion
n.运动,移动
  • By land,air or sea,birds are masters of locomotion.无论是通过陆地,飞越空中还是穿过海洋,鸟应算是运动能手了。
  • Food sources also elicit oriented locomotion and recognition behavior patterns in most insects.食物源也引诱大多数昆虫定向迁移和识别行为。
5 sensors
n.传感器,灵敏元件( sensor的名词复数 )
  • There were more than 2000 sensors here. 这里装有两千多个灵敏元件。 来自《简明英汉词典》
  • Significant changes have been noted where sensors were exposed to trichloride. 当传感器暴露在三氯化物中时,有很大变化。 来自辞典例句
6 leverage
n.力量,影响;杠杆作用,杠杆的力量
  • We'll have to use leverage to move this huge rock.我们不得不借助杠杆之力来移动这块巨石。
  • He failed in the project because he could gain no leverage. 因为他没有影响力,他的计划失败了。
7 acceleration
n.加速,加速度
  • All spacemen must be able to bear acceleration.所有太空人都应能承受加速度。
  • He has also called for an acceleration of political reforms.他同时呼吁加快政治改革的步伐。
8 acting
n.演戏,行为,假装;adj.代理的,临时的,演出用的
  • Ignore her,she's just acting.别理她,她只是假装的。
  • During the seventies,her acting career was in eclipse.在七十年代,她的表演生涯黯然失色。
标签: SSS sidewalk
学英语单词
'uns
agrarian relations
aluminium hydoxide
architectural environment
atmospherization
auricular arteries
backtrack cancel
beat somebody black and blue
bembeneks
bichord
biological satellite
bradycardic
cathedratical
census of housing
chief development officer
Codariocalyx motorius
convexity at central section
counter pinning
cutlass-fish
Demoivre's theorem
diaper lover
Diospyros embryopteris
direct memory access transfer
dma transfer
down-bow
elephanta
epi-wilsonine
Erythrina variegata
ester wax
eurostar
film mulching
flexible electrode
flight check (fltck)
FMN
galvanized steel strap
gasometric determination
gastroptosis
Gessertshausen
high alumina clay
history of characters
homage
huisht
IADB
Iltutmish
induced ovulation
jefferts
Jilib
kurung
lun li wu tao
mac mahon fort
malfunction flag
measuring transducer
mechanical tissue
merit pays
Mt. St. Helens
negtive
nomadologist
nonovernight
nonsatirical
notch wire filter
nuchal scans
Nīzgān
one-manys
orthojector circuit-breaker
penknife ice
pony-tailed
population dispersal
pot farms
primary relationship
profit
proserpines
psychopharmaceuticals
repeated crossing
retract rearward
roentgen-equivalent-mammal
Ruawuri
sales meeting
sarcopia
screw type pulverized coal feeder
slantwise
sleep ... off
solanapyrone
speed of turn over
square rebated joint
stock-removing efficiency
stylode
successive-approximation method
Sungaipenuh
Tan Hiep
task light
thyromodulin
toclase syrup
trade share
tutorest
underestimators
wail for
waste furnish
weather echo
weather proof plywood
well car
white-on-white
witchman