时间:2018-12-18 作者:英语课 分类:2018年NPR美国国家公共电台2月


英语课

Have you ever heard predictions that one day women will be able to have babies without men? It turns out that some species of the Whiptail lizard 1 have figured out how to do this and completely eliminated the male sex.

你是否曾听说过某一天女性将不需要男性也可生小孩?事实上一些种类的长尾蜥蜴已经可以做到这一点,并将全部的雄性完全消灭掉了。



Females Cloning Themselves

雌性克隆自身



The females have the ability to lay eggs that hatch and grow into healthy lizards 2 without needing to be fertilized 3 by a male. The offspring are exact and complete genetic 4 duplicates of the mothers.

无须借助雄性受孕,雌性蜥蜴有能力产下可以孵化出健康的小蜥蜴的蛋。其后代完全是母亲们基因的复制品。



Essentially 5 the females are clonnig themselves.

这在本质上是雌性在克隆自己。



Role Playing

角色扮演



If that weren’t enough, the female lizards take turns role-playing. They perform a mating ritual in which one lizard acts like the male, and the second lizard acts like the female. The ritual causes the lizard acting 6 as the female to ovulate and lay her eggs. Then, a few weeks later, the two lizards switch roles and repeat this process so that the second female will be able to ovulate and lay her eggs.

如果这还不够的话,雌性蜥蜴会轮流扮演角色。她们在交配过程中,一只扮演雄性,另一只扮演雌性。交配将使扮演雌性的蜥蜴排卵产蛋。几周之后,两只蜥蜴互换角色重复交配过程从而使得另一只雌性得以排卵。



Genetic Variation

遗传变异



It raises a lot of interesting questions. For example, it’s not clear how well an all female species can evolve and adapt to environmental changes. A species’ survival depends in part on variation among its members. If all the members of a species are identical, chances are greater that something like a change in the climate or a disease will wipe them all out.

这引发了许多有意思的问题。例如,我们尚不清楚一个完全由雌性组成的种群在面临环境变化是能否很好地适应和进化。一个种群的存在,部分地取决于其内部成员的多样性。如果一个种群中所有的成员具有同一性,那么当环境剧变或疾病肆虐时,它们的灭绝概率也将更大。

 



1 lizard
n.蜥蜴,壁虎
  • A chameleon is a kind of lizard.变色龙是一种蜥蜴。
  • The lizard darted out its tongue at the insect.蜥蜴伸出舌头去吃小昆虫。
2 lizards
n.蜥蜴( lizard的名词复数 )
  • Nothing lives in Pompeii except crickets and beetles and lizards. 在庞培城里除了蟋蟀、甲壳虫和蜥蜴外,没有别的生物。 来自辞典例句
  • Can lizards reproduce their tails? 蜥蜴的尾巴断了以后能再生吗? 来自辞典例句
3 Fertilized
v.施肥( fertilize的过去式和过去分词 )
  • The study of psychology has recently been widely cross-fertilized by new discoveries in genetics. 心理学研究最近从遗传学的新发现中受益匪浅。
  • Flowers are often fertilized by bees as they gather nectar. 花常在蜜蜂采蜜时受粉。
4 genetic
adj.遗传的,遗传学的
  • It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
  • Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
5 essentially
adv.本质上,实质上,基本上
  • Really great men are essentially modest.真正的伟人大都很谦虚。
  • She is an essentially selfish person.她本质上是个自私自利的人。
6 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。
学英语单词
act of mercy
Adenophora verticillata
adm.
agammaglobulinemics
aggregative response
All-Ordinaries Index
Amchitka Island
amount of the original contribution
anr-pc
anterior radiocarpal ligaments
arrabbiata
arsenic-fast
auto increment addressing mode
Bacillus satellitus
bacterial speck
Belemnopteris
bic
blumpken
breaking test for chain cable
Brewster window
Canada Day
caudal medullary vestige
cecchettis
chenopodium glaucums
Chuvanayskiye Gor'y
classification of income
comb dresser
convergioscope
cooled shroud
cropping management factor
crucible holder
cruset
dense-graded mix
descending development method
difezil
diffusion of impurities
digital increment plotter
dilute medium
down sb's way
efferent limb block
fourth normal form
foveate
freak-out
friscoes
ground points
hartenberger
hartzog
have a sweet tooth
Hedyotis coreana
heterogeneous multiplexing
hysterophyte
installation risk
instruction classification
integrating ahead
Japanese rice ball
kehon odori (japan)
Kellyana
keyword density
king philip
lead-cadmium elimination roast
leaf cycle
liljeros
line-intercept
liquid blasting
lovelocked
mail bag
materfamiliases
milk ring test
monomorium minimums
mother's
multiple ultrasonic transducer combination
Newcomb theory
noncytoplasmic
nucleothymic acid
obtrectation
one-way controlled transmission
pan-fired
Panofsky, Erwin
panophthalmitis
Pirthipur
plagiorchis
playgames
Pontet-Canet
preselected trajectory
quilliam
resource sharing control
resuspensions
road pizza
roamings
Sabinas Hidalgo
scullery basin
shuttingdown
smsas-s
Tagore
test equipment tool
thin achromatic doublet
tooth plane
ursus thibetanus formosanus
vehicle repair depot
Victor Charlie
weak absorption