首页
登录
职称英语
What evolutionary change in birds led to a nest’s building? [originaltext] Ma
What evolutionary change in birds led to a nest’s building? [originaltext] Ma
游客
2023-10-21
59
管理
问题
What evolutionary change in birds led to a nest’s building?
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、Their flying ability improved greatly.
B、They became warm-blooded.
C、They began to lay eggs.
答案
B
解析
文中此句For this,they needed a place—a nest中的For this是指上文when they be-came warm-blooded creatures living in cold places,they had to remain on the eggs to keepthem warm,故B项正确。
转载请注明原文地址:http://tihaiku.com/zcyy/3116206.html
相关试题推荐
Massivechangesinalloftheworld’sdeeplycherishedsportinghabitsareu
Readcarefullythefollowingexcerptonhistoricalbuildings,andthenwrite
(1)Twosidesalmostneverchange:Thatyoucanmanipulatepeopleintoself-
(1)Overthepastdecade,therehasbeenaseachangeinChina’seconomicpo
(1)Overthepastdecade,therehasbeenaseachangeinChina’seconomicpo
[originaltext]W:Goodmorning,John.IamLucy.M:Goodmorning.W:Howareyou
[originaltext]W:Goodmorning,John.IamLucy.M:Goodmorning.W:Howareyou
[originaltext]W:Goodmorning,John.IamLucy.M:Goodmorning.W:Howareyou
[originaltext]W:Hi,John,itisgoodtoseeyou.M:Samehere,Nancy.Ithasb
[originaltext]W:Hi,John,itisgoodtoseeyou.M:Samehere,Nancy.Ithasb
随机试题
Marketriskreferstotheriskof______.A、defaultB、financialpricesfluctuation
Bloggingisapastimeformany,evenalivelihoodforafew.Forsome,itbe
Canelectricitycausecancer?Inasocietythatliterallyrunsonelectricp
闪婚(flashmarriage)这一都市情感快餐已在我国不少城市悄然登场。青年男女,尤其是20一30岁之间的青年,闪电相识,爱情速配,已成为一种时尚。
A. B. C.葡萄糖 D.白蛋白血浆胶体渗透压的形成主要取决于()
患者男,45岁。经常咳嗽,最近出现咯血。痰液经抗酸染色,在蓝色背景上出现细长、粉
下列对注射用油的质量要求描述不正确的是A.无异臭,无酸败味B.碘值、皂化值、酸值
工程保险属于工程建设项目风险的()应对措施。A.风险回避B.风险转移C.风险
以下说法正确的是( )。A.2015年5月1日,国务院公布《存款保险条例》
古道西风有限公司被裁定进入破产程序,根据《破产法解释(三)》,下列选项正确的是?
最新回复
(
0
)