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
2023-10-15
31
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] 【R1】
选项
答案
a phenomenon
解析
(由原文These are examples of co—evolution,a phenomenon first described by Charles Darwin可知答案。)
转载请注明原文地址:https://tihaiku.com/zcyy/3101019.html
相关试题推荐
Mygardenhaslargetrees.Mygardenhasflowerswhichsmelllovelywheninbloo
-WhatamIgoingtodoaboutapresentforCarol?-You______someflowers.A、mig
Mygardenhaslargetrees.Mygardenhasflowerswhichsmelllovelywheninbloo
Someofthesensesthatweandotherterrestrialmammalstakeforgrantedar
Someofthesensesthatweandotherterrestrialmammalstakeforgrantedar
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
Aseveryschoolboyknows,insectspollinateflowers,whilebirdsandmammals
随机试题
Motivationis"thedrivingforcewithinindividualsthatimpelsthemtoacti
PASSAGEFOURWhydidthegirlplaybasketballoverandoveragain?[br]Whatis
Googlemustbethemostambitiouscompanyintheworld.Itsstatedgoal,"to
关于以连续三年停止使用为由申请撤销商标注册的案件,用以证明系争商标不存在连续三年
不属于霍奇金病组织学分型的是( )。A.淋巴细胞为主型 B.结节硬化型 C
医院使用麻醉乙醚时,打开安瓿24小时后A.视其颜色有无变化,决定是否可以使用
磷存在于我们的DNA中,是构成生命的基本元素之一。但它早期是如何到达地球的仍是一
唯物辩证法认为,事物的运动、变化、发展都离不开联系。这主要表现在()。 A.事
关于担保概念的表述中,不正确的是( )。A.担保通常由当事人双方订立担保合同
关于侵蚀性葡萄胎的特点、诊断和治疗,下列哪项错误 A.多发生在葡萄胎术后6个月
最新回复
(
0
)