首页
登录
职称英语
All mammals feed their young. Beluga whale mothers, for example, nurse their
All mammals feed their young. Beluga whale mothers, for example, nurse their
游客
2025-02-07
35
管理
问题
All mammals feed their young. Beluga whale mothers, for example, nurse their calves for some twenty months, until they are about to give birth again and their young are able to find their own food. The behavior of feeding of the young is built into the reproductive system. It is a nonelective part of parental care and the defining feature of a mammal, the most important thing that mammals-- whether marsupials, platypuses, spiny anteaters, or placental mammals -- have in common.
But not all animal parents, even those that tend their offspring to the point of hatching or birth, feed their young. Most egg-guarding fish do not, for the simple reason that their young are so much smaller than the parents and eat food that is also much smaller than the food eaten by adults. In reptiles, the crocodile mother protects her young after they have hatched and takes them down to the water, where they will find food, but she does not actually feed them. Few insects feed their young after hatching, but some make other arrangement, provisioning their cells and nests with caterpillars and spiders that they have paralyzed with their venom and stored in a state of suspended animation so that their larvae might have a supply of fresh food when they hatch.
For animals other than mammals, then, feeding is not intrinsic to parental care. Animals add it to their reproductive strategies to give them an edge in their lifelong quest for descendants. The most vulnerable moment in any animal’s life is when it first finds itself completely on its own, when it must forage and fend for itself. Feeding postpones that moment until a young animal has grown to such a size that it is better able to cope. Young that are fed by their parents become nutritionally independent at a much greater fraction of their full adult size. And in the meantime those young are shielded against the vagaries of fluctuating of difficult-to-find supplies. Once a species does take the step of feeding its young, the young become totally dependent on the extra effort. If both parents are removed, the young generally do no survive. [br] The word "provisioning" in line 13 is closest in meaning to
选项
A、supplying
B、preparing
C、building
D、expanding
答案
A
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3947066.html
相关试题推荐
[img]2012q1/ct_etoefm_etoefspeakc_0346_20121[/img]Usingpointsandexamplesf
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
Allmammalsfeedtheiryoung.Belugawhalemothers,forexample,nursetheir
[img]2012q1/ct_etoefm_etoefspeakc_0119_20121[/img]Usingexamplesanddetails
"Thermoregulation"Mammalsandbirdsgenerallymaintainbodytemperaturewith
随机试题
Ascientistwhowantstopredictthewayinwhichconsumerswillspendthei
IsthereenoughoilbeneaththeArcticNationalWildlifeRefuge(保护区)(ANWR)to
______,Iagreewithyourestimateofthesituation.A、InthewayB、InonewayC
[originaltext]Wouldyouliketogoswimmingwithmethisafternoon?[/originalte
关于中国共产党历史上的重要会议,下列说法不正确的是:A.古田会议:解决了建设新型
生产厂应根据产量和生产设备条件将混凝土外加剂分批编号,掺量小于1%的外加剂每一批
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性: A.如
皮亚杰的“三山实验”考察的是()A.儿童的深度知觉 B.儿童的计数
下列行为不构成伪造金融票证罪的是()。A:伪造、变造汇票、本票、支票B:伪造委
(2021年真题)下列各项中,关于有限责任公司资本公积的表述正确的是( )A.
最新回复
(
0
)