首页
登录
职称英语
[originaltext] Human population near the equator have evolved dark skin over
[originaltext] Human population near the equator have evolved dark skin over
游客
2025-02-06
26
管理
问题
Human population near the equator have evolved dark skin over many generations because of exposure to the fiercest rays of the sun. A similar phenomenon has also occurred in other parts of the animal kingdom. The African grass mouse is a good example. Most mice are nocturnal, but the African grass mouse is active during daylight hours. This means that it spends its days searching for food in the semi-dry bush in squired habitats of eastern and southern Africa. Its furry stripe’s like a chipmunk’s, which helps it blend in with its environment.
Because it spends a lot of time in the intense tropical sun, the grass mouse has also evolved two separate safeguards against the sun’s ultraviolet radiation. First, like the population of humans in this region of the world, the skin of the grass mouse contains lots of melanin, or dark pigment. Second and quite unusual, this mouse has a layer of melanin pigmented tissue between its skull and skin. This unique cap provides an extra measure of protection for the grass mouse and three other types of African mouse, like rodents that are active during the day. The only other species scientists have identified with the same sort of skull of that occasion is the white camp-making bat of the Central American tropic. Although these bats sleep during the day, they do so curled up with their head exposed to the sun.
选项
A、They are active during daylight hours
B、Their heads are exposed to sunlight while they sleep
C、They have only partially adapted to their tropical environment
D、Their wings are easily damaged by ultraviolet radiation
答案
B
解析
Why do white camp-making bats need protection from the sun’s rays?
转载请注明原文地址:https://tihaiku.com/zcyy/3945778.html
相关试题推荐
[originaltext]Finallythereisonemoreelementtobusinesssuccessthatwe
[originaltext]Finallythereisonemoreelementtobusinesssuccessthatwe
[originaltext]M:Isthatamap?Areyougoingsailingorsomething?W:Iwish.
[originaltext]M:Isthatamap?Areyougoingsailingorsomething?W:Iwish.
[img]2012q2/ct_etoefm_etoefspeaka_0444_20124[/img][originaltext]StudentAIwa
[originaltext]W:Hi,Dan,youknowthatlabyoumissed?Youcanhavemynotes.
[originaltext]W:Hi,Dan,youknowthatlabyoumissed?Youcanhavemynotes.
[img]2012q1/ct_etoefm_etoefspeakc_2097_20121[/img][originaltext]Professor
[img]2012q2/ct_etoefm_etoefspeakc_0447_20124[/img][originaltext]The"greenh
[originaltext]W:HeySteve,gotanyplansfortonight?M:Hi,Jane.No,Idon’
随机试题
[originaltext]Doyouknowwhyweinstalledtheextratelephones?(A)Yes,theyj
Lastyear,sheearned______hellhusband,whohasabetterposition.A、threetim
以下不符合《营业性演出管理条例》的是()。A.演出举办单位应当为文化稽查人
A.儿童外伤后,局部骨皮质和骨小梁扭曲,看不见骨折线 B.外力经过骺板达干骺端
大多数药物在体内转运的主要方式是()。A.易化扩散 B.简单扩散 C.过滤
A.心悸气短,动则加剧,胸闷心痛,咳唾 B.喘促气逆,不能平卧,痰稀量多,形寒
脑主司感觉运动,有赖于A、脑髓充养 B、营血充养 C、肾精充养 D、肝血充
Thedoctorshaveabandonedthehopetor
各种运输方式内外部的各个方面的构成和联系,就是( )。 A.运输系统
某企业的产品生产按照工艺顺序需连续经过甲车间、乙车间、丙车间、丁车间的生产才能完
最新回复
(
0
)