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
80
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
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage1?Inboxes11-13onyouranswersheet,writeTR
Choosethecorrectletter,A,B,CorD.Writeyouranswerinbox40onyouranswersheet.Whatisthemainthemeofthepassage?
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage2?Inboxes19-24onyouranswersheet,writeTR
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage3?Inboxes34-40onyouranswersheet,writeTR
Youshouldspendabout20minutesonQuestions27-40whicharebasedonReadingPassage3below.THEINGENUITYGAPIngenuity,as
Youshouldspendabout20minutesonQuestions27-40,whicharebasedonReadingPassage3below.ArtificialartistsCancompute
LivingDunesWhenyouthinkofasanddune,youprobablypictureabarrenpileoflifelesssand.Butsanddunesareactuallydyn
WhichpiechartshowstheagesoftheAsianstudentssurveyed?WhichpiechartshowsthemainreasonsAsianstudentswantedto
WhichTWOthingsintherainforestdoesthespeakergiveawarningabout?
Whichattitudeisassociatedwiththefollowingpeopleduringtheconversation?ChooseSIXanswersfromtheboxandwritetheco
随机试题
行政案件由违法行为人居住地公安机关管辖更为适宜的,可以由违法行为人居住地公安机关管辖,但是涉及卖淫、嫖娼、赌博、毒品的案件除外。
对于非法批准而使用的土地,当事人必须予以退还。如果拒不退还的,当事人就要承担()的法律责任。
房地产开发项目应当建立资本金制度,资本金占项目总投资的比例不得低于20%。()
某工程施工中,关于推荐性技术标准T的适用问题,有关各方产生了争议,下列观点中正确的是()。
根据《物权法》的规定,预告登记后,自能够进行不动产登记之日起()个月内未申请登记的,预告登记失效。
事业单位办理备案登记时,需提供行政属地( )的证明材料。
赵峰是班里的数学科代表,不仅数学成绩好,其他各科成绩也都名列前茅。可是,他上课时发言积极,课余时间却不愿意与同学主动交流,也不喜欢参加班集体活动,显得有些冷漠,每当有同学向他请教问题时,他总是先强调一下:“连这样的题你都不会做?……那好吧,就由我来教教你吧
我国社会主义初级阶段是指()的阶段。
在数据库系统中,当数据库的模式改变时,用户程序可以不做改变。这是数据的
Playistheprincipalbusinessofchildhood,andmoreandmoreinrecentyearsresearchhasshownthegreatimportanceofplayi
最新回复
(
0
)