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
2024-01-04
30
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/3332506.html
相关试题推荐
CyclingholidayinAustriaExampleAnswerMostsuitableholidaylasts__10__days
CyclingholidayinAustriaExampleAnswerMostsuitableholidaylasts__10__days
CyclingholidayinAustriaExampleAnswerMostsuitableholidaylasts__10__days
CyclingholidayinAustriaExampleAnswerMostsuitableholidaylasts__10__days
CyclingholidayinAustriaExampleAnswerMostsuitableholidaylasts__10__days
TransportfromBayswaterExampleDestinationHarbourCityExpr
TransportfromBayswaterExampleDestinationHarbourCityExpr
TransportfromBayswaterExampleDestinationHarbourCityExpr
TransportfromBayswaterExampleDestinationHarbourCityExpr
HotelbookingenquiryExampleDestination:VancouverHotelname:Holiday【L1】____
随机试题
Thelastheart-poundingraceoftheSummerGamesendedSundayinawhitemar
Thatpeopleoftenexperiencetroublesleepinginadifferentbedinunfamili
病人法律权利中,________要求医务人员对待不同病人一视同仁,在分配医疗卫生
根据以下资料,回答下列问题。 2010年1~6月,全国电信业务收入总量累计完
重大劳动安全卫生事故处理对策的内容包括( )。A.重大劳动安全卫生事故处理对策
某女52岁。患慢性支气管炎10年,受寒后引发咳嗽经久不愈痰少而黄、无发热,口不渴
A.巴比妥类 B.丝裂霉素C C.珍氯片 D.四环素 E.左甲状腺素四逆
(2019年真题)期末同一合同下的合同资产净额大于合同负债净额的差额,如超过一年
发电厂中,高压厂用电系统短路电流计算时,考虑以下哪几项条件?()A.应按可能发
(2015年)下列废水处理方法中,属于利用密度差异去除污染物的有:()。A.板
最新回复
(
0
)