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
75
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://kaotiyun.com/show/uUyO777K
0
托福(TOEFL)
相关试题推荐
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage2?Inboxes19-24onyouranswersheet,writeTR
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage2?Inboxes19-24onyouranswersheet,writeTR
Youshouldspendabout20minutesonQuestions27-40whicharebasedonReadingPassage3below.TheRainmakerSometimesideasj
Youshouldspendabout20minutesonQuestions27-40,whicharebasedonReadingPassage3below.ArtificialartistsCancompute
HowdesertsareformedA.Adesertreferstoabarrensectionofland,mainlyinaridandsemi-aridareas,wherethereisal
EducationPhilosophyA.Althoughwelackaccuratestatisticsaboutchildmortalityinthepre-industrialperiod,wedohave
WhichthreeforeignlanguagesaretraditionallytaughtintheUSA?HowoldaretheyoungestschoolchildrenlearningChinese?
Gestures—especially______ones.Put______onboardandstudentslabelit.
Theprofessorsaysthatsuperhighways______.【27】
ChooseTWOletters,A-E.WhichTWOpre-existingfeaturesofthesitearenowpartofthenewfacilities?AfootballstadiumBpl
随机试题
患者,女,40岁。该病人自30岁患原发性“高血压”病。多年来经常头晕胀痛,心烦易怒并伴腰膝酸软无力,手足心热,潮热盗汗,舌红少苔,脉弦细数。辨证为
有头疽初期,外用方为有头疽溃脓期,外用方为
税务机关干部张某向个体工商户李某征税,李某要求减免,张某拒不同意,李某便对其妻说:“你去找张某,不惜一切手段把减免税这件事办成。”李某之妻便找到张某,与张某发生了性关系。几天后,张某仍旧要求李某纳税,李便说:“五天之内你要么批准我的免税申请,要么拿一万块钱
现浇混凝土墩台施工中,模板设计应包括()内容。
以下选项符合证券自营业务运作管理要求的是()。
中小学教师职业道德教育的内容主要包括政治理论、法律法规、教师心理及健康教育等。()
网络时代,个人隐私被侵犯已经成为很多网民的______与困扰。公民个人信息通过网络被泄露、个人电脑被黑客人侵、网上购物清单被人留底等情况时有发生。一种普遍的不安全感______在网络世界,不同程度地影响着人们的正常工作和生活。填入横线部分最恰当的一
A、1B、0C、3D、出现错误提示A
新建文档WD12B.DOC,插入文档WD12A.DOC,将标题“习惯与自然”设置为黑体、小二号、居中;正文部分的汉字设置为宋体,字号为四号,字形为“加粗”,存储为文档WD12B.DOC。
Inmanystressfulsituationsthebody’sresponsescanimproveourperformance.Webecomemore【B1】______,morealert,betterabl
最新回复
(
0
)