首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Zoology Animal Defenses Based on the information in the lecture, indicate whether each situation below involves camouflage, che
Zoology Animal Defenses Based on the information in the lecture, indicate whether each situation below involves camouflage, che
admin
2012-01-14
70
问题
Zoology Animal Defenses
Based on the information in the lecture, indicate whether each situation below involves camouflage, chemical weapons, or warning coloration. For each sentence, click in the correct box. This question is worth 2 points.
One of the most important relationships between different animal species is predation—the predator-prey interaction, in which a predator eats a prey. Predator species have several adaptations that help them catch prey species. Prey species have adaptations, too—physical and behavioral adaptations that enable them to elude predators and avoid being eaten. These defensive adaptations evolved in prey species through repeated encounters with predators over evolutionary time.
Some animal defenses are passive, such as hiding. Some defenses are active, such as escaping. Fleeing—running away—is the most direct anti-predator response, but it requires the animal to expend a lot of energy. A rabbit uses up a lot of energy running away from a lynx. Many animals avoid expending too much energy by escaping into a shelter.
Several prey species have some sort of vocalization—an alarm call—to announce the presence of a predator. The alarm call often triggers a behavioral defense called mobbing. During mobbing, the prey turns the tables and attacks the predator. For example, when a chickadee spots a threat—say, an owl—it calls out the alarm. The chickadee starts scolding the owl, sometimes actually striking it from behind. Birds of other species may fly in to investigate, and often participate in the mobbing. The other birds chase, dive-bomb, or surround the owl, usually vocalizing loudly. Their intent is to encourage the "enemy" to move on to another area.
Some animals rely on defensive coloration. A well-known example of defensive coloration is camouflage, which makes prey difficult to spot against a background of similar color. All a camouflaged animal has to do is remain still to avoid being seen. Thus, camouflage is probably the most effective passive defense. Incidentally, some predators also use camouflage, especially predators who lie in wait for prey and have to blend into their environment.
Moths that camouflage themselves to match a leaf stand a good chance of not being seen by moth-eating birds, unless, of course, the moths become so populous that a bird is likely to come across one by accident. Once the bird learns the moth’s identity, it has a search image for it, and the moth’s disguise is useless. Looking like a leaf is then no advantage because the bird will start pecking at leaves in the hope that they are moths, and it will keep doing it as long as a sufficient number do turn out to be moths.
Another animal defense is the use of chemical weapons. We’re all familiar with the chemical weapon of the skunk. Some animals—like poisonous toads and flogs—can synthesize toxins that attack the nervous system of predators. Other animals acquire chemical defenses passively. For example, some caterpillars acquire poison from the plants they eat. Then, when a bird eats the caterpillar, the bird quickly vomits. After that, the bird will avoid eating that kind of caterpillar. Some birds can remember bad-tasting meals a year later.
Another defensive adaptation is warning coloration. Animals with effective chemical defenses are often brightly colored, and there is evidence that predators are more cautious in dealing with bright color patterns in potential prey. This is probably because a lot of poisonous or bad-tasting animals are colored brightly, with black and yellow, or black and red stripes.
Warning coloration quickly trains predators to avoid eating these brightly-colored animals. Some birds have an instinctive tendency to avoid eating insects with warning coloration. For example, young warblers leave wasps alone because the birds recognize the danger in the black and yellow stripes of the wasp. However, warning coloration is not an absolute defense, as there is also evidence showing that many birds occasionally feed on bees and wasps, perhaps after learning to cope with their chemical defenses.
选项
答案
Chemical weapons: A toad squirts a nerve poison from glands on its back: ...poisonous toads and frogs--can synthesize toxins that attack the nervous system of predators. Camouflage: A fish cannot be seen against rocks of the same color: ...camouflage, which makes prey difficult to spot against a background of similar color. Warning coloration: A bird avoids eating a black and yellow striped wasp: ...young warblers leave wasps alone because the birds recognize the danger in the black and yellow stripes of the wasp. Camouflage: An insect disguises itself to look like a leaf: Moths that camouflage themselves to match a leaf stand a good chance of not being seen....(2.5)
解析
转载请注明原文地址:https://www.kaotiyun.com/show/uUyO777K
0
托福(TOEFL)
相关试题推荐
Completethesummarybelow.ChooseNOMORETHANTHREEWORDSfromthepassageforeachanswer.Writeyouranswersinboxes18-25
Completethesummarybelow.ChooseNOMORETHANTHREEWORDSfromthepassageforeachanswer.Writeyouranswersinboxes18-25
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage3?Inboxes34-40onyouranswersheet,writeTR
CompletethesentencesbelowusingNOMORETHANTWOWORDSfromthepassage.Writeyouranswersinboxes23-26onyouranswershe
Youshouldspendabout20minutesonQuestions1-13whicharebasedonReadingPassage1below.ManorMachine?MIT’shumanoidr
Youshouldspendabout20minutesonQuestions1-13,whicharebasedonReadingPassage1below.AAmericanstodaychooseamong
LivingDunesWhenyouthinkofasanddune,youprobablypictureabarrenpileoflifelesssand.Butsanddunesareactuallydyn
Moreonlineusersofsocialnetworkingsitesovertheageof45allowstrangerstoseetheirphotosthanothergroups.
AncientPeopleinSaharaOnOct.13,2000,PaulSereno,aprofessorfromtheUniversityofChicago,guidedateamofpalaeon
TheConceptofChildhoodinWesternCountriesThehistoryofchildhoodhasbeenaheatedtopicinsocialhistorysincetheh
随机试题
下列关于施工合同的义务,说法正确的有()。
以下哪项与维持身体平衡和姿势无关
对患者进行口腔检查时发现其某颗指数牙的龈上牙石覆盖面积为牙面的1/3~2/3,根据简化牙石指数,应计为
下列对基准收益率理解不正确的是()。
A公司为支付购货款,向B公司签发银行承兑汇票一张,甲银行已经承兑。B公司取得汇票后,将其背书转让给C公司以支付购货款,在背书时,B公司在汇票背面第一个背书栏内签章,但将“被背书人名称”处留白,直接将汇票交付给C公司。C公司取得汇票后,在被背书人栏内记载自己
李某是某公司生产部门主管,该部门有20多名员工,其中既有生产人员又有管理人员,该部门采用的考评方法是排列法,每年对员工考评一次。具体做法是:根据员工的实际表现给其打分,每个员工最高分为100分,上级打分占30%,同事打分占70%。在考评时,20多个人互相打
如图,在△ABC中,D、E两点分别在AB、AC边上,DE//B若DE:BC=2:3,则S△ADE:S△ABC________。
智育的任务主要限于传授科学文化知识。
请在【答题】菜单下选择【进入考生文件夹】命令,并按照题目要求完成下面的操作。注意:以下的文件必须保存在考生文件夹下。书娟是海明公司的前台文秘,她的主要工作是管理各种档案,为总经理起草各种文件。新年将至,公司定于2013年2月5日下午2:00,在中关村海
UsingFacebookmakespeoplesadder,atleastaccordingtosomeresearch.Butjustwhatisitaboutthesocialnetworkthattakes
最新回复
(
0
)