时间:2019-02-16 作者:英语课 分类:英语听力广播—Listening


英语课
【英文原文】
Sometimes the biggest finds are the smallest finds. Researchers examining a segment of siltstone taken from ground along the Beardmore glacier 1 in Antarctica found something unexpected. They found a fly.
Well, not exactly a fly. They found a fly fossil–it’s a segment of the exoskeleton, the protective shell, of a fly larva. While the larvae 2 are still growing, they are protected by a thin shell. And where there’s larval shell, there are flies. So what are flies doing in Antarctica? It’s much too cold there for flies. And the closest fly-friendly location, South America, is thousands of miles away.
Part of the answer is that the fly fossil is ancient–it was found with a number of other fossilized things that have been dated between three million and seventeen million years old. It’s possible that the fly lived during a period when sea levels were much lower there than they now are. Lower sea levels means wider continents –think of standing 3 on the edge of a beach and having the water pull back. And wider continents means its more likely that living things might travel across the gap.
Or maybe not. Maybe flies are much older than anyone thought. We know that what we now call Antarctica was once connected to both South America and Australia. But that was around eighty million years ago, and flies aren’t thought to be that old.
Whatever the answer is, something in our understanding of the continents, the seas, or fly evolution has to be fixed 4. That’s one of the best things about science–a really big change can come from the discovery of something really small.

n.冰川,冰河
  • The glacier calved a large iceberg.冰河崩解而形成一个大冰山。
  • The upper surface of glacier is riven by crevasses.冰川的上表面已裂成冰隙。
n.幼虫
  • Larvae are parasitic on sheep.幼虫寄生在绵羊的身上。
  • The larvae prey upon small aphids.这种幼虫以小蚜虫为食。
n.持续,地位;adj.永久的,不动的,直立的,不流动的
  • After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
  • They're standing out against any change in the law.他们坚决反对对法律做任何修改。
adj.固定的,不变的,准备好的;(计算机)固定的
  • Have you two fixed on a date for the wedding yet?你们俩选定婚期了吗?
  • Once the aim is fixed,we should not change it arbitrarily.目标一旦确定,我们就不应该随意改变。
学英语单词
acetylphosphoric acid
approbated
arteriola efferens
assembler loader package
babusar pass
basivolsella
beef stroganoffs
biosphere reserve
black teals
blandished
board bridge
breanna
calcium pyrophosphate
chemical insecticide
clear panel key
colouring book
computer forensics
cool-summer damage due to impotency
Cuproartinite
customs compound
customs supervision
decaudates
direct current source
documents-against-payment bill
DTRTT
electric resistance wire
enthalpy-entropy chart
excess mean portfolio return
firmware support
food-purchasing
four-address code
friction pressure
ghiaour
greys
Hawkins Point
hedonic price method
high-tempreature strain gauge
hovde
hyperpipecolatemia
intraploidy
job-lot production
kellwood
Keota
Koh Sla, Stung
lightly deformed crystal
lindeberg's condition
liquefaction temperature
Lloyd's anchors and chains proved
Loxwood
lymphonoduli aggregati
Madipelesa
magnaliums
mark sth up
megawatt (mw)
micromechanically
momentum cutoff
muhs
myristicic acid
nonutilized
obituarial
OGRL
Omlet
on-line cipher
orbiculately
ortho-nitraniline
Os Draconis
philosoph
piratesses
possessive pronoun
pritchie
pseudoprognathism
pulpitless
Q clearance
R. M. S.
rauca
reattend
remote sensing for atmospheric pollution
residual current operated protective device
Rhododendron mainlingense
sassen
sea language
see ... do
self-redemptions
simple HISAM data base
Skave
steam water interface
steering gear tube cam
stratum compactum of integument
stress bolt
suicide bombing
synchronization
tatouay
Thai Ridgebacks
thorotrast
turite
type of machine
varnish-treated tape
vigna angulariss
wage tax
wheeler and dealer
worm-gears