时间:2018-12-27 作者:英语课 分类:英语时差8,16


英语课

Why Shrews Twitter Small mouse like mammals, shrews are not actually rodents 1 or even closely related. Shrews are noisy little creatures– constantly twittering and squeaking 2 as they scramble 3 through their habitat. But why? All that noise could surely attract the attention of predators 4, so there must be an important reason for their endless twittering. One possibility is that shrews use calls for communicating with neighbors or mates. But some researchers have hypothesized that the twittering serves a totally different function– echolocation. Since shrews have poor eyesight, listening to the way their calls echo back from the surroundings might help them navigate 5 through their environment. A team of German biologists reasoned that if calls were used solely 6 for communication, then calling behavior should change depending on the presence or absence of other shrews. But if calls were used for echolocation, calling should change in response to changes in the physical surroundings rather than social situations. The researchers discovered that the twittering of shrews did not change in response to the simulated presence or absence of other shrews. But when the researchers changed the thickness of the straw bedding in the shrews’ enclosures, the rate of twittering changed too. This suggests that shrews may use their calls as a simple type of echolocation, and not only for communication. The echoes from their calls help them navigate in the dark and avoid obstacles in their path. Although more research is needed to understand how shrews use their twitter calls in the wild, the discovery is exciting news since shrews are one of the first land animals that might use echolocation.



1 rodents
n.啮齿目动物( rodent的名词复数 )
  • Rodents carry diseases and are generally regarded as pests. 啮齿目动物传播疾病,常被当作害虫对待。 来自《简明英汉词典》
  • Some wild rodents in Africa also harbor the virus. 在非洲,有些野生啮齿动物也是储毒者。 来自辞典例句
2 squeaking
v.短促地尖叫( squeak的现在分词 );吱吱叫;告密;充当告密者
  • Squeaking floorboards should be screwed down. 踏上去咯咯作响的地板应用螺钉钉住。 来自《简明英汉词典》
  • Can you hear the mice squeaking? 你听到老鼠吱吱叫吗? 来自《简明英汉词典》
3 scramble
v.爬行,攀爬,杂乱蔓延,碎片,片段,废料
  • He broke his leg in his scramble down the wall.他爬墙摔断了腿。
  • It was a long scramble to the top of the hill.到山顶须要爬登一段长路。
4 predators
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面)
  • birds and their earthbound predators 鸟和地面上捕食它们的动物
  • The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
5 navigate
v.航行,飞行;导航,领航
  • He was the first man to navigate the Atlantic by air.他是第一个飞越大西洋的人。
  • Such boats can navigate on the Nile.这种船可以在尼罗河上航行。
6 solely
adv.仅仅,唯一地
  • Success should not be measured solely by educational achievement.成功与否不应只用学业成绩来衡量。
  • The town depends almost solely on the tourist trade.这座城市几乎完全靠旅游业维持。
学英语单词
389
abutting on
adrenal veins (or suprarenal veins)
Alaprodate
appraise by expert
arithlog diagram
atween
australian-owned
ballast machine
base diffusive layer
bastard verdict
bateleur
bicolo(u)r
blue bore
caloriferous
ceiling load
china l.
Chinese checker
circulating scrap
clare-obscure
collinear condition
competition curve
conclusive evidence
concrete of dry consistency
control material
Corydalis nematopoda
day book
drawn down profile
early morels
entombers
EOE
epdm-rubber
ethnologische
evaporation surface
gelotherapy
general subroutine
go up to town
helium-atmosphere
high temperature dyeing machine
hired acceptance
hot-beef injection
hydraulic (closure) stud tensioner
illinformed
initial survey and test of cargo gear
JCSS
Korifasi
lamp wiring
M6
Makua
malarial granuloma
many-windowed
margaret mitchells
martinus
mcmichael
mumblingly
murderbots
mustron
Neotremata
nonneuroleptic
Northern Div.
open-flux-path
Pavlov, Ivan Petrovich
payment credit
percentage cover
pertussin
phase-displaced current
phone lines
photon noise
pin fin
potentiometric optical pyrometer
power conditioning unit
pump reflector
quoited
radiator flap handle
remelted pig iron
renal graft biopsy
right left needle
runway observation
sale on credit
Sarcina intestinalis
scanning antenna mount
shell belt
Shirāni
shsis-s
soar up
solid centre
solid gold
spongy surface
spouted bed drier
ST_science_scientific-techniques
stopped short
strontium lanthanum chromate ceramics
surcle
swell-
televisor
thimble tube-oil-fired type
uniform completeness
weightlessnesses
What the Papers Say
xiongnu
yearly maximum
zhongshan