首页
登录
职称英语
As every schoolboy knows, insects pollinate flowers, while birds and mammals
As every schoolboy knows, insects pollinate flowers, while birds and mammals
游客
2024-08-11
9
管理
问题
As every schoolboy knows, insects pollinate flowers, while birds and mammals disperse seeds by eating fruits or transporting burs on their feathers and fur. These are examples of co-evolution, a phenomenon first described by Charles Darwin in The Descent of Man, and Selection in Relation to Sex, published in 1871.
Co-evolution, in which two species have evolved together in response to adaptations that each has imposed on the other, can be extremely subtle. For instance, some animals may help to transfer pollen from one plant to another without acting directly as the carrier themselves. Instead, they make it easier for the pollen to be dispersed by other creatures. Mats Olsson and Richard Shine, of the University of Sydney, and Elisabeth Bak-Olsson, of the University of Gothenburg in Sweden, have discovered, apparently for the first time, such a mutually beneficial arrangement between a reptile and a plant.
For most of the year the Tasmanian snow skink lizard confined to mountain tops in that island is catholic in what it eats. But when the honey-bush is in bloom, the skinks make a point of tearing off the tough, red petals that enclose the rest of the flower. They chew them to extract the nectar and spit out what is left. At first sight, this skink-savaging may not seem all that helpful to the honey-bush. But it is. It exposes the reproductive parts of the flowers, thereby allowing pollinating insects to get at them. Dr. Olsson and his colleagues found that flowers with the petals left intact never produced seed. But, according to their paper in the Biological Journal of the Linnean Society, 87% of flowers with the petals torn off did so.
To check that it was the skinks alone that were the plants’ little helpers, the researchers placed cages around some honey-bushes. Virtually all of the petals were removed from the flowers on bushes without cages. Only 16% of the caged bushes had their petals ripped off, possibly by high winds battering them.
Dr. Olsson found no evidence of pollen being carried on a skink and so concluded that the lizards play no role in transporting honey-bush pollen from one flower to another. But he did see a range of insects: wasps, flies, bumble-bees and others feeding from honey-bush flowers that had no petals covering them. Without the petals removed, it was impossible for insects to do any pollinating.
Question 71 to 75
Complete the summary below with information from the passage, using three words or fewer for each blank.
Co-evolution is【R1】______described by Charles Darwin in The Descent of Man. In the process of co-evolution, two species may have to respond to adaptations they have imposed on each other.
For example, some animals may not carry【R2】______from one plant to another. They may help by making it easier for other creatures to disperse the pollen from one plant to another. Such an arrangement seems【R3】______to both species. In Tasmania, the skink lizards chew the red petals of【R4】______and spit out what is left. In doing so, they expose the reproductive parts of the flower and enable pollinating insects to reach them. It was discovered that 87% of these flowers produced seeds. Conversely, flowers with petals remaining【R5】______never did. [br] 【R3】
选项
答案
beneficial
解析
(由第二段such a mutually beneficial arrangement between a reptile and a plant可知答案。)
转载请注明原文地址:https://tihaiku.com/zcyy/3714900.html
相关试题推荐
Mygardenhaslargetrees.Mygardenhasflowerswhichsmelllovelywheninbloo
Mygardenhaslargetrees.Mygardenhasflowerswhichsmelllovelywheninbloo
Someofthesensesthatweandotherterrestrialmammalstakeforgrantedar
Someofthesensesthatweandotherterrestrialmammalstakeforgrantedar
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
随机试题
Theguestpaid(little)______moneythanheshouldfortheroom.less本题考查形容词比较级的用法
唐三彩(theTangtri-coloredglazedpottery)是一种以黄、褐、绿为基本色的陶器(ceramics),它盛行于唐代,距今
中风的中医健康干预主要是( )。A.发现中风先兆及时综合干预 B.发病期扶正
下列关于受益权的转让、撤销和丧失的说法,正确的有()。 A.受益权在转化为现
可一日数次对同一地点扫描,并用它观察城市热岛的变化情况的主体是( )。A.气象
《资政新篇》的主要内容有( ) A.政治上,主张加强中央集权 B.经济上,
健脾康儿片既能健脾养胃,又能A.消食止泻 B.止咳化痰 C.泻火通便 D.
以设备寿命期周期成本为基础的评标价法包括的费用是()。A.估算寿命期内所需
肝硬化的重要实验室诊断依据是A.ALT升高 B.白蛋白下降及A/G比值倒置
某工程单代号网络图如下所示,工期为()。 A.9 B.11 C.12 D
最新回复
(
0
)