豹身上为何会有斑点
文章来源:未知 文章作者:meng 发布时间:2010-10-21 00:59 字体: [ ]  进入论坛
(单词翻译:双击或拖选)

Why do leopards2 have rosette(莲座丛) shaped markings but tigers have stripes? Rudyard Kipling suggested that it was because the leopard1 moved to an environment "full of trees and bushes and stripy, speckly, patchy-blatchy shadows" but is there any truth in this just-so story? Researchers at the University of Bristol investigated the flank(侧面) markings of 35 species of wild cats to understand what drives the evolution of such beautiful and intriguing3 variation. They captured detailed4 differences in the visual appearance of the cats by linking them to a mathematical model of pattern development.

They found that cats living in dense5 habitats, in the trees, and active at low light levels, are the most likely to be patterned, especially with particularly irregular or complex patterns. This suggests that detailed aspects of patterning evolve for camouflage6(伪装,掩饰) . Analysis of the evolutionary7 history of the patterns shows they can evolve and disappear relatively8 quickly.

The research also explains why, for example, black leopards are common but black cheetahs9(印度豹,猎豹) unknown. Unlike cheetahs, leopards live in a wide range of habitats and have varied10 behavioural patterns. Having several environmental niches11 that different individuals of the species can exploit allows atypical(非典型的) colours and patterns to become stable within a population.

Although a clear link between environment and patterning was established, the study also highlighted some anomalies(异常现象) . For example, cheetahs have evolved or retained spotted12 patterns despite a strong preference for open habitats, while a number of cats, such as the bay cat and the flat-headed cat, have plain coats despite a preference for closed environments. Why this should be remains13 unclear.

The study also highlighted just how few species of cats have vertical14 stripes. Of the 35 species examined, only tigers always had vertically15 elongated16(细长的) patterns and these patterns were not associated with a grassland17 habitat, as might be expected. However, tigers seem to be very well camouflaged18 so this raises the question why vertical stripes are not more common in cats and other mammals.

Will Allen of Bristol's School of Experimental Psychology19, who led the research, said: "The method we have developed offers insights into cat patterning at many levels of explanation and we are now applying it to other groups of animals."



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1 leopard n9xzO     
n.豹
参考例句:
  • I saw a man in a leopard skin yesterday.我昨天看见一个穿着豹皮的男人。
  • The leopard's skin is marked with black spots.豹皮上有黑色斑点。
2 leopards 5b82300b95cf3e47ad28dae49f1824d1     
n.豹( leopard的名词复数 );本性难移
参考例句:
  • Lions, tigers and leopards are all cats. 狮、虎和豹都是猫科动物。 来自《简明英汉词典》
  • For example, airlines never ship leopards and canaries on the same flight. 例如,飞机上从来不会同时运送豹和金丝雀。 来自英语晨读30分(初三)
3 intriguing vqyzM1     
adj.有趣的;迷人的v.搞阴谋诡计(intrigue的现在分词);激起…的好奇心
参考例句:
  • These discoveries raise intriguing questions. 这些发现带来了非常有趣的问题。
  • It all sounds very intriguing. 这些听起来都很有趣。 来自《简明英汉词典》
4 detailed xuNzms     
adj.详细的,详尽的,极注意细节的,完全的
参考例句:
  • He had made a detailed study of the terrain.他对地形作了缜密的研究。
  • A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。
5 dense aONzX     
a.密集的,稠密的,浓密的;密度大的
参考例句:
  • The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
  • The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。
6 camouflage NsnzR     
n./v.掩饰,伪装
参考例句:
  • The white fur of the polar bear is a natural camouflage.北极熊身上的白色的浓密软毛是一种天然的伪装。
  • The animal's markings provide effective camouflage.这种动物身上的斑纹是很有效的伪装。
7 evolutionary Ctqz7m     
adj.进化的;演化的,演变的;[生]进化论的
参考例句:
  • Life has its own evolutionary process.生命有其自身的进化过程。
  • These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。
8 relatively bkqzS3     
adv.比较...地,相对地
参考例句:
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
9 cheetahs 49fe48184ec612a4c6ab48e2544552ef     
n.(奔跑极快的)非洲猎豹( cheetah的名词复数 )
参考例句:
  • Unlike lions or cheetahs, leopards are secretive, solitary cats. 花豹不像狮子或印度豹,是属于较神秘而隐居的大猫。 来自互联网
  • Among this lot are cheetahs, lions, leopards, rhinoceroses, spotted hyenas and elephants. 印度豹、狮子、花豹、犀牛、斑点土狼、大象等,都是此地的居民。 来自互联网
10 varied giIw9     
adj.多样的,多变化的
参考例句:
  • The forms of art are many and varied.艺术的形式是多种多样的。
  • The hotel has a varied programme of nightly entertainment.宾馆有各种晚间娱乐活动。
11 niches 8500e82896dd104177b4cfd5842b1a09     
壁龛( niche的名词复数 ); 合适的位置[工作等]; (产品的)商机; 生态位(一个生物所占据的生境的最小单位)
参考例句:
  • Some larvae extend the galleries to form niches. 许多幼虫将坑道延伸扩大成壁龛。
  • In his view differences in adaptation are insufficient to create niches commensurate in number and kind. 按照他的观点,适应的差异不足以在数量上和种类上形成同量的小生境。
12 spotted 7FEyj     
adj.有斑点的,斑纹的,弄污了的
参考例句:
  • The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
  • Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。
13 remains 1kMzTy     
n.剩余物,残留物;遗体,遗迹
参考例句:
  • He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
  • The remains of the meal were fed to the dog.残羹剩饭喂狗了。
14 vertical ZiywU     
adj.垂直的,顶点的,纵向的;n.垂直物,垂直的位置
参考例句:
  • The northern side of the mountain is almost vertical.这座山的北坡几乎是垂直的。
  • Vertical air motions are not measured by this system.垂直气流的运动不用这种系统来测量。
15 vertically SfmzYG     
adv.垂直地
参考例句:
  • Line the pages for the graph both horizontally and vertically.在这几页上同时画上横线和竖线,以便制作图表。
  • The human brain is divided vertically down the middle into two hemispheres.人脑从中央垂直地分为两半球。
16 elongated 6a3aeff7c3bf903f4176b42850937718     
v.延长,加长( elongate的过去式和过去分词 )
参考例句:
  • Modigliani's women have strangely elongated faces. 莫迪里阿尼画中的妇女都长着奇长无比的脸。
  • A piece of rubber can be elongated by streching. 一块橡皮可以拉长。 来自《用法词典》
17 grassland 0fCxG     
n.牧场,草地,草原
参考例句:
  • There is a reach of grassland in the distance.远处是连绵一片的草原。
  • The snowstorm swept the vast expanse of grassland.暴风雪袭击了辽阔的草原。
18 camouflaged c0a09f504e272653daa09fa6ec13da2f     
v.隐蔽( camouflage的过去式和过去分词 );掩盖;伪装,掩饰
参考例句:
  • We camouflaged in the bushes and no one saw us. 我们隐藏在灌木丛中没有被人发现。 来自《现代英汉综合大词典》
  • They camouflaged in bushes. 他们隐蔽在灌木丛中。 来自《简明英汉词典》
19 psychology U0Wze     
n.心理,心理学,心理状态
参考例句:
  • She has a background in child psychology.她受过儿童心理学的教育。
  • He studied philosophy and psychology at Cambridge.他在剑桥大学学习哲学和心理学。
TAG标签: species tigers leopards
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