首页
登录
职称英语
What evolutionary change in birds led to a nest’s building? [br] [originaltext]
What evolutionary change in birds led to a nest’s building? [br] [originaltext]
游客
2024-08-22
39
管理
问题
What evolutionary change in birds led to a nest’s building? [br]
Many egg-laying animals merely lay their eggs and leave. Turtles, for instance, and horseshoe crabs, the eggs are hatched and the little ones are on their own. The current theory about birds is the earliest birds did just that when they were cold-blooded creatures living in warm places. However, when they became warm-blooded creatures living in cold places, they had to remain on the eggs to keep them warm. For this, they needed a place—a nest. Very likely, the first nest was just a primitive hole scraped in the ground. Even now many species still lay eggs in this sort of crude nest. Primitive nests found on the ground were fine for some birds, but others began to elevate their nests in branches, perhaps to avoid predators. These early elevated nests were probably cup-shaped nest. This type is still built by some birds today. The latest development in nest, the most recent vision, so to speak, is the cup-shaped nest. This is the one we regard today as the typical bird’s nest, you know, like a robin’s nest.
选项
A、To avoid predators.
B、To expose the eggs to stronger sunlight.
C、To have a better view of predators.
答案
A
解析
根据此句others began to elevate their nests in branches,perhaps to avoid predators,可知A项正确。
转载请注明原文地址:http://tihaiku.com/zcyy/3731069.html
相关试题推荐
Wheredidthethiefstealthecarsfrom?[br][originaltext]W:...andnowtolo
Wheredidthethiefstealthecarsfrom?[br][originaltext]W:...andnowtolo
Wheredidthethiefstealthecarsfrom?[br][originaltext]W:...andnowtolo
Whataretheytalkingabout?[br][originaltext]W:Hi,Tony.How’sthenewjob
Whataretheytalkingabout?[br][originaltext]W:Hi,Tony.How’sthenewjob
WhydoesRuthcallJackie?[br][originaltext]W:Hi,Jackie!We’regoingtoaf
WhydoesRuthcallJackie?[br][originaltext]W:Hi,Jackie!We’regoingtoaf
Howwillthepricebedetermined?[br][originaltext]M:HowshouldIpricethes
Howwillthepricebedetermined?[br][originaltext]M:HowshouldIpricethes
Howwillthepricebedetermined?[originaltext]M:HowshouldIpricethesecalc
随机试题
AfterWorldWar11theglorificationofaneverlargerGNPformedthebasis
Inwhatnowseemsliketheprehistorictimesofcomputerhistory,theearly
______isthelargestcityinScotland.A、CardiffB、EdinburghC、GlasgowD、Manchest
已知反应,当反应达平衡后,欲使反应向右进行,可采取的方法是:A.升温,升压
工程清单项目特征描述的重要意义有哪些?
根据迈克尔?波特的竞争战略理论,当一家银行的实力范围狭窄、资源有限时,专业化策略
金银花不适用的病证是()。A.痈肿疔疮B.外感风热C.肺痈乳痈D.热毒泻痢E.
A.出生到1岁 B.1岁至1岁半 C.2岁 D.2岁半 E.3岁出生后,
根据下列资料回答问题。 以下为某省的人口失业率图表。其中,黑色部分表示该省全省
对同一宗房地产而言,关于其土地价值、建筑物价值和房地价值的表述中,错误的是( )
最新回复
(
0
)