科学美国人60秒 SSS 2013-09-11
时间：2019-01-20 作者：英语课 分类：Scientific American(九)月
英语课
In the east African savanna 1, pools of water form during the rainy season only to dry up a few months later. Being a fish in one of these temporary ponds is a challenge. To survive, they race to maturity 2, with the shortest generation time of any vertebrate.
To monitor the development of the so-called annual fish, researchers raised two different species in the lab.
The fish could grow by almost a quarter of their body length each day. One species could already reproduce at 17 days of age. The other took an additional day. The eggs these youngsters fertilized 3 then hatched in as little as 15 days, leaving only a month between generations. The study is in the journal EvoDevo.
Embryonic 4 annual fish survive the dry season by lying dormant 5 underground. Once the rains return and the pool forms, they quickly reproduce before the water dries up again. Their short generation time is thus a crucial evolutionary 6 adaptation. Their temporary ponds force them to live fast, die young and leave a desiccated corpse 7.
n.大草原
- The savanna is also the home of meat-eaters--the lion,leopard,and hyena who feed on the grasseaters.大草原也是食肉动物的家乡--狮子、豹、鬣狗--它们都是以草食动物维持生命的。
- They sped upon velvet wheels across an exhilarant savanna.他们的马车轻捷地穿过一片令人赏心悦目的大草原。
n.成熟；完成；(支票、债券等)到期
- These plants ought to reach maturity after five years.这些植物五年后就该长成了。
- This is the period at which the body attains maturity.这是身体发育成熟的时期。
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。
adj.胚胎的
- It is still in an embryonic stage.它还处于萌芽阶段。
- The plan,as yet,only exists in embryonic form.这个计划迄今为止还只是在酝酿之中。
adj.暂停活动的；休眠的；潜伏的
- Many animals are in a dormant state during winter.在冬天许多动物都处于睡眠状态。
- This dormant volcano suddenly fired up.这座休眠火山突然爆发了。
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。