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
2023-10-21
35
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、A hole scraped in the ground
B、Cup-shaped nest
C、Platforms of sticks and dried leaves
答案
B
解析
从倒数第二句The latest development in nest,the most recent vision,so to speak,is thecup-shaped nest.可知鸟巢的最新形式是杯状。
转载请注明原文地址:https://tihaiku.com/zcyy/3116500.html
相关试题推荐
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
A.incomeB.polarizationC.transformationsD.oldE.changesF.worse
随机试题
Therearemanywaysinwhichthephenomenaoflanguageandcultureareintim
WaystoGetaHappyStateofMind
Peoplemaybethemostinterestingshowinalargecity.Strollthroughbusiness
煤气灶台高度一般是()m。A.0.6 B.0.7 C.0.8 D.0.
影响X线照片密度的因素错误的是A.照射量 B.管电压 C.摄影距离 D.被
张某,女,30岁,教师。身高165cm,体重60公斤。平时喜欢喝牛奶,吃烤牛肉,
A.-6q B.6q C.0 D.p
下列辅助检查对鉴别格林-巴利综合征和脊髓灰质炎有价值的是A.血常规 B.肌肉活
既能凉血止血,又能收敛止血,解毒敛疮的药物是( ) A.侧柏叶 B.大蓟
患者女,15岁,诊断为急性扁桃体炎,给予抗菌药物治疗。青霉素皮试:(-)。但肌内
最新回复
(
0
)