时间:2018-12-30 作者:英语课 分类:托福听力短文


英语课
(WA) Before moving on to a new topic, I want to finish up our unit on arachnids by looking at what may seem a very unusual aspect of spider behavior --- a species where the young spiders actually consume the body of their mother.

Unlike most other spiders, this species lays one --- and only one --- clutch of 40 eggs in her lifetime. The young spiders hatch in mid-spring or early summer, inside a nest of eucalyptus 1 leaves. Their mother spends the warm summer months bringing home large insects --- often 10 times her weight --- for meal. The catch is always significantly more than her young spiders can eat. So, the mother fattens 2 herself up on this extra prey 3 and stores the nutrients 4 in her extra (unfertilized) eggs. As the weather turns colder, there are fewer insect prey to hunt. That's when the nutrients stored in those extra eggs begin to seep 5 into the mother's bloodstream. So, when there are no more insects to feed to the young spiders, they attach themselves to the mother's leg joints 6 and draw nourishment 7 by sucking the nutrient-rich blood.

After several weeks, the mother is depleted 8 of all nutrients and she dies. But then how do the young get nourishment? They start to feed on one another. Now, if you recall our discussion of Darwin, you'll see the evolutionary 9 value of this: Only the strongest spiders of the clutch will survive this "cannibalism," and the mother spider will have ensured that her genes 10 have an increased chance of survival through future generations.


n.桉树,桉属植物
  • Eucalyptus oil is good for easing muscular aches and pains.桉树油可以很好地缓解肌肉的疼痛。
  • The birds rustled in the eucalyptus trees.鸟在桉树弄出沙沙的响声。
v.喂肥( fatten的第三人称单数 );养肥(牲畜);使(钱)增多;使(公司)升值
  • The weekly with large fattens on sex, crime and scandal. 这家发行量甚大的周刊靠宣染性、罪和丑闻打开销路。 来自互联网
  • It boosts consumers' real incomes and fattens firms' profit margins. 这将增加消费者的收入提高企业的利润幅度。 来自互联网
n.被掠食者,牺牲者,掠食;v.捕食,掠夺,折磨
  • Stronger animals prey on weaker ones.弱肉强食。
  • The lion was hunting for its prey.狮子在寻找猎物。
n.(食品或化学品)营养物,营养品( nutrient的名词复数 )
  • a lack of essential nutrients 基本营养的缺乏
  • Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
v.渗出,渗漏;n.渗漏,小泉,水(油)坑
  • My anger began to seep away.我的怒火开始消下去了。
  • If meteoric water does not evaporate or run overland,it may seep directly into the ground.如果雨水不从陆地蒸发和流走的话,就可能直接渗入地下。
接头( joint的名词复数 ); 关节; 公共场所(尤指价格低廉的饮食和娱乐场所) (非正式); 一块烤肉 (英式英语)
  • Expansion joints of various kinds are fitted on gas mains. 各种各样的伸缩接头被安装在煤气的总管道上了。
  • Expansion joints of various kinds are fitted on steam pipes. 各种各样的伸缩接头被安装在蒸气管道上了。
n.食物,营养品;营养情况
  • Lack of proper nourishment reduces their power to resist disease.营养不良降低了他们抵抗疾病的能力。
  • He ventured that plants draw part of their nourishment from the air.他大胆提出植物从空气中吸收部分养分的观点。
adj.进化的;演化的,演变的;[生]进化论的
  • Life has its own evolutionary process.生命有其自身的进化过程。
  • These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。
n.基因( gene的名词复数 )
  • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
  • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
学英语单词
accessing formula
acid cooled rocket engine
arangoes
artcurial
Attagenus piceus
backtrack mode
blue stellar object
bukkaked
Calycophyllum
Cap Breton Canyon
cargo wire
Chalcolithic Age
change level
cheatees
cohesive soil
core physics calculation
correlation of coal seam
Cosford
cropping system
cup-counter anemometer
cybister brevis
Cyperus haspan
Darawati
deoxycorticosteroid
engineering in medicine
Erigeron himalajensis
family secotiaceaes
feed chain
floorboard
fourb
fusc
general over supply
great pyreneess
Greentomatocars
hematogenic infectious disease
hiriline
hot face
igbesanmwan
imageology
individual axle drive locomotive
inner and outer ring
ipomoea pes-caprae brasiliensis
keep to somewhere
Kharaulakhskiy Khrebet
lash-likest
lightening plate frame
lumbered
maide
main valve plunger
mica window
Mikmaks
monotheist
mushroom coreprint
New Internationalist
nuclear endosperm
numeric pictured arithmetic item
nurgles
out-sprout
output constraint
oxygen-free copper
pay a call of nature
phacelia
phossy jaw
pilot-drill
piratize
polder model
positive regulator gene
postmortem pustule
praisings
pre-supposes
presymptom
pretty-in-pink
prominence streamer
propeller screw
publish or perish
puts the kibosh on
quinquevalence
quintrate
radens
rat's-tail cactus
registered deposit-taking company
relief port
rigid foundation structure
Sallustian
screen definition facility
sealing effect
sharu
shelter-deck vessel
specially moulded brick
sri lankas
St. Elias Mountains
steering-compass course
study of investment opportunities
substance abuse disorder
superminifloppy
sutura nygomaticofrontalis
tent ring
trobriand
uncrashworthy
unisparker
water-lily tulip