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
abnormal release
ActiveSync
al-hamid
aniline oil
automatic screwdown control
birthlands
blind love
blood feuds
bottom bearing shell
branchialia
brittle metals
bulkhead luminaire
calculating punch(er)
cavalletto
Celadin
circular saw charpener
cobbra
coextended
cold medicine
concentration by electrodecantation
core instruments
corroding electrode
critically acclaimed
cross-week
cut-out box
cytotetrin
demension
demystify
driving part
dudgen
earnings inequality
emaciate
environmental index
Epigonichthyidae
espy
ethofumesate
fatty acid inositol ester
fork guide
fortunateling
gastrocnemial ridge
george grove
gnophomyia (gonomyia) nansei
grand canonical assemblage
ground duty
haplohumult
heavily doped layer
homoneura (homoneura) discoidalis
Interest Rate Floor
interstitial cystitis
isobaric motion
language of thought
localizer (loc)
lp record
Luculia gratissima
lx
maigas
marezzo marble
maximum likelihood stochastic language
method of development
monopalmitin
motorcycle cobination
natural ordered
niece-in-law
nitrotrimethylolmethane
non-conformance
nozzle cover
oceanic tholeite
Odontochilus bisaccatus
overall rating
parazoans
passes the buck
penetrant technique (pt)
Phyllostachys parvifolia
physical data base name
pianetas
PIC (program interrupt control)
poppets
positive conductor
pour the baby out with the bath
putty glazing
quopped
Radial Rolling Force
red horse
relativistic dynamics
renewle
replacement cost
reverse coupler
rivet holder
scholles
set one's jaw
ship wave observation
short-circuit test
snobberies
stow-wood
t cell erythroderma
the Falkland Islands
tracking of ions
unrigorous
vacuum-tube emission
voltage of electric organs
wood box back
yoick