托福阅读背景资料bird

托福阅读真题之鸟类的进化话题托福阅读真题之鸟类的进化话题多数同学在做托福阅读练习时会找托福阅读的以往试题，除了TPO的练习题，其他很多试题都是比较零散的，所以复习起来很费劲，那么到哪里可以找到托福阅读真题来练习呢？今天新通教育就为大家总结了10篇托福阅读真题：鸟类的进化话题，同时附带问题和答案，希望可以为大家的复习带来帮助。

托福阅读文章：The first flying vertebrates were true reptiles in which one of the fingers of the front limbs became very elongated, providing support for a flap of stretched skin that served as a wing. These were the pterosaurs, literally the "winged lizards." The earliest pterosaurs arose near the end of the Triassic period of the Mesozoic Era, some 70 million years before the first known fossils of true birds occur, and they presumably dominated the skies until they were eventually displaced by birds. Like the dinosaurs, some the pterosaurs became gigantic; the largest fossil discovered is of an individual that had a wingspan of 50 feet or more, larger than many airplanes. These flying reptiles had large, tooth-filled jaws, but their bodies were small and probably without the necessary powerful muscles for sustained wing movement. They must have been expert gliders,not skillful fliers, relying on wind power for their locomotion.1Birds, despite sharing common reptilian ancestors with pterosaurs, evolved quite separately and have been much more successful in their dominance of the air. They are an example of a common theme in evolution, the more or less parallel development of different types of body structure and functionfor the same reason —in this case, for flight. Although the fossil record, as always, is not complete enough to determine definitively the evolutionary lineage of the birds or in as much detail as one would like, it is better in this case than for many other animal groups. That is because of the unusual preservation in a limestone quarry in southern Germany of Archaeopteryx, a fossil that many have called the link between dinosaurs and birds. Indeed, had it not been for the superb preservation of these fossils, they might well have been classified as dinosaurs. They have the skull and teeth of a reptile as well as a bony tail, but in the line-grained limestone in which these fossils occur there are delicate impressions of feathers and fine details of bone structure that make it clear that Archaeopteryx was a bird. All birds living today, from the great condors of theAndes to the tiniest wrens, trace their origin back to the Mesozoic dinosaurs.托福阅读题目：21. What does the passage mainly discuss?(A) Characteristics of pterosaur wings(B) The discovery of fossil remains of Archaeopteryx(C) Reasons for the extinction of early flying vertebrates(D) The development of flight in reptiles and birds2. Which of the following is true of early reptile wings?(A) They evolved from strong limb muscles.(B) They consisted of an extension of skin.(C) They connected the front and back limbs.(D) They required fingers of equal length.3. The word "literally" in line 3 is closest in meaning to(A) creating(B) meaning(C) related to(D) simplified4. It can be inferred from the passage that birds were probably dominant in the skies(A) in the early Triassic period(B) before the appearance of pterosaurs(C) after the decline of pterosaurs(D) before dinosaurs could be found on land.35. The author mentions airplanes in line 8 in order to(A) illustrate the size of wingspans in some pterosaurs(B) compare the energy needs of dinosaurs with those of modern machines(C) demonstrate the differences between mechanized flight and animal flight(D) establish the practical applications of the study of fossils6. The word "They" in line 10 refers to(A) powerful muscles(B) bodies(C) jaws(D) flying reptiles7.According to the passage , pterosaurs were probably "not skillful fliers" (lines 10-11) because(A) of their limited wingspan(B) of their disproportionately large bodies(C) they lacked muscles needed for extended flight(D) climate conditions of the time provided insufficient wind power8. In paragraph 2, the author discusses the development of flight in birds as resulting from(A) a similarity in body structure to pterosaurs4(B) an evolution from pterosaurs(C) the dominance of birds and pterosaurs over land animals(D) a separate but parallel development process to that of pterosaurs9. The word "classified" in line 21 is closest in meaning to(A) perfected(B) replaced(C) categorized(D) protected10. Which of the following helped researchers determine thatArchaeopteryx was not a dinosaur?(A) Its tail(B) Its teeth(C) The shape of its skull(D) Details of its bone structure11. What is the significance of the discovery that was made in southern Germany?(A) It is thought to demonstrate that birds evolved from dinosaurs.(B) It is proof that the climate and soils of Europe have changed over time.(C) It suggests that dinosaurs were dominant in areas rich in limestone.5(D) It supports the theory thatArchaeopteryx was a powerful dinosaur.托福阅读答案：DBBCADCDCDA以上就是新通教育为大家提供的托福阅读真题之鸟类的进化话题内容，希望可以为大家的托福阅读练习带来帮助，更多内容请点击6。

智课网TOEFL备考资料托福阅读机经：不会飞行的鸟类摘要：托福阅读机经：不会飞行的鸟类.以前，存在没有翅膀的鸟。

因为它们生活在岛屿上，没有天敌。

这种鸟翅膀肌肉不发达是因为发展翅肌的能量还不如自己保存体力。

又说到后来它们因为环境等因素不得不进化，而没有进化的鸟就因为人类入侵而灭绝了。

不会飞的鸟是指已失去飞行能力的鸟类，取而代之的是奔跑及游泳的能力。

虽然如此，但普遍相信它们都是由懂得飞行的共同祖先进化而来。

现存约有40种不会飞的鸟类，包括企鹅、鸵鸟及鹬鸵(奇异鸟)等广为人知的物种，及部分属于其他目的物种。

除了诸如鸵鸟等大型的不会飞的鸟仍拥有强而有力的爪去对抗猎食者之外，大部分不会飞的鸟所面对的均为没有太多捕猎者的环境、或是隔绝性的海岛，花费极大气力的飞行并不符合效益，因此它们的进化倾向失去这种能力。

相比起其他地区，新西兰有较多的不会飞的鸟类，如奇异鸟、企鹅及南秧鸡等。

其中一个原因是在人类首次踏足这个土地上时(约1000年前)，岛上并没有地栖形的捕猎者，它们最大的敌人反而是大型的猛禽——飞行并不是逃避敌人的有效方法。

不会飞的鸟类在面对人类所造成的威胁时冲击较大，因此它们面临灭绝的机会也较高;幸运的是它们也较易被圈养保护，简单的栏杆已是有效的工具。

人类很早就懂得牧养鸵鸟以取得其羽毛，现在的规模更大，以取得其肉作食及皮作为皮革制品。

【英文题源】Flightless birds are birds which lack the ability to fly, relying instead on their ability to run or swim. They are thought to haveevolved from flying ancestors. There are about forty species in existence today, the best known being the ostrich, emu, cassowary, rhea, kiwi, and penguin. It is believed by somecitation needed that most flightless birds evolved in the absence of predators on islands, and lost the power of flight because they had few enemies — although this is likely not the case for the ratites (the ostrich, emu and cassowary), as all have claws on their feet to use as a weapon against predators.Two key differences between flying and flightless birds are the smaller wing bones of flightless birdsand the absent (or greatly reduced) keel on their breastbone. The keel anchors muscles needed for wing movement. Flightless birds also have more feathers than flying birds.There are at least another two possibilities as to why flightless birds such as ostriches and emus have wings, either.The wings are indeed “useless” and derivedfrom birds that once could fly. This is possible in the creationist model. Loss of features is relatively easy by natural processes, whereas acquisition of new characters, requiring specific new DNA information, is impossible. Loss of wings most probably occurred in a beetle species that colonized a windy island. Again, this is a loss of genetic information, so it is not evidence for microbe-to-man evolution, which requires masses of new genetic information.Some possible functions, depending on the species of flightless bird, are: balance while running, cooling in hot weather, warmth in cold weather, protection of the ribcage during falls, mating rituals, scaring predators (emus will run at perceived enemies of their chicks, mouth open and wings flapping), sheltering of chicks, etc. If the wings are useless, why are the muscles functional, allowing these birds to move their wings?New Zealand has more species of flightless birds than any other country. One reason is that until the arrival of humans roughly a thousand years ago, there were no large land predators in New Zealand; the main predators of flightless birds were larger birds.The flightless birds of New Zealand are a principal feature of the 'edge ecology' of the country.In an island environment isolated fromthe rest of the world for more than 80 million years, and free of mammal predators, a number of birds developed flightlessness andeccentric habits. Each of them filled different ecological functions; moa and kakapo as forest browsers, takahe as grass eaters, and kiwi and wrens as ground insect eaters - roles taken by mammals in other ecosystems. Many of the birds are unafraid of humans, a common characteristic resulting from the absence of predators, which became deadly when human hunters arrived. The takahe, for example, is the largest living member of the rail family which is found throughout the Southern Oceanic islands.They were hunted until they were rarely found in the 19th century. None were seen after 1900 and it was declaredextinct, but amazingly, 200 pairs were found in a remote region of Fiordland in 1948. The North Island takahe is extinct, but about 220 of the South Island species continue their dramatic brink of extinction existence.Some flightless varieties of island birds are closely related to flying varieties, implying flight is a significant biological cost.The smallest flightless bird is the Inaccessible Island Rail (length 12.5 cm, weight 34.7 g). The largest (both heaviest and tallest) flightless bird, which is also the largest living bird, is the Ostrich (2.7 m, 156 kg), although some extinct species grew to larger sizes.Flightless birds are the easiest to take care of in captivity because they do not have to be caged. Ostriches were once farmed for their decorative feathers. Today they are raised for meat and for their skins, which are used to make leather.There were also other families of flightless birds, such as the now extinct Phorusrhacidae, that evolved to be very powerful terrestrial predators.【托福高频词】evolvedcitationfromderivedroughlypredatorseccentricdramaticextinctterrestrial【长难句分析】It is believed by some citation needed that most flightless birds evolved in the absence of predators on islands, and lost the power of flight because they had few enemies — although this is likely not the case for the ratites (the ostrich, emu and cassowary), as all have claws on their feet to use as a weapon against predators.Some possible functions, depending on the species of flightless bird, are: balance while running, cooling in hot weather, warmth in cold weather, protection of the ribcage during falls, mating rituals, scaring predators (emus will run at perceived enemies of their chicks, mouth open and wings flapping), sheltering of chicks, etc.Many of the birds are unafraid of humans, a common characteristic resulting from the absence of predators, which became deadly when human hunters arrived.相关推荐:托福阅读机经背景：印加古国的书写系统托福阅读机经：英国农业的发展托福阅读机经：婴幼儿的记忆能力相关字搜索：托福阅读机经背景复习。

【托福阅读真题解析】鸟群2017年9月9日的考试真题解析已经出来了，阅读考试题目有哪些呢?托福栏目小编整理了相关的资料，希望可以帮助考生度过考试的难关，下面是小编搜集的托福阅读真题解析相关资讯，欢迎参考!Passage Three学科分类：生物题目：Bird coloniesPassage3新托福阅读题目回忆版本一:birds colonies这篇文章讲的是birds colonies，先讲了它为什么会形成，然后说了birds colonies的优缺点。

优点是可以防天敌，也能通过跟着其他鸟来找食物，举了yellow-rumped birds和cliff swallow的例子。

然后说了适合居住的地方，一般是食物比较充足的地方，或者是个别物种适应的cold water区域。

但缺点是面临着竞争，鸟会各种互相争。

但总的来说还是优点outweigh缺点1. vicinity = region2. contribute to = add to3. exhaust= use up4. on balance= overall新托福阅读题目回忆版本二:Bird Colony 重复2017.4.15先说了什么情况下鸟会聚集在一起，举了一种黄色小鸟的例子，在colony边缘的窝要比中心的窝更易损(vulnerable)，所以colony中心的鸟窝分布密度很大。

鸟类住在colony当中有好处也有坏处，好处是比如可以躲避predator、一起孵蛋(hatch eggs)、share食物信息等。

其中对付predator的手段有三种：一是集群攻击，二是用废弃的窝(abandoned nest)和新窝混合在一起迷惑敌人，三是把窝建在W鸟窝的周围，predator就不会靠近。

这些方法中，一三鸟群受到的伤害最少。

关于一起孵蛋，即便有被天敌吃掉的蛋，但总会有漏网之鱼(outnumber)活下来。

最后说到食物来源(food supply)，colony一般在食物来源的周围分布，还说到了一个食物丰富的地方，但是给鸟类留下的落脚点很少，所以就会使鸟群集中。

托福阅读tpo75R-1原文+译文+题目+答案+背景知识原文 (1)译文 (5)题目 (8)答案 (17)背景知识 (17)原文Clutch Size in Birds①Each year the emperor penguin lays one egg, the pigeon lays one or two eggs, the gull typically lays three eggs, the Canada goose four to six eggs, and the American merganser ten or eleven eggs. What determines clutch size in birds? The ultimate factors that determine clutch size are the requirements for long-term (evolutionary)survival. Clutch size is viewed as an adaptation under the control of natural selection.②Natural selection will favor those birds that leave the mostdescendants to future generations. At first thought we might hypothesize that natural selection favors a clutch size that is the physiological maximum the bird can lay. We can test this hypothesis by taking eggs from nests as they are laid. When we do this, we find that some birds, such as the common pigeon, are determinate layers; they lay a given number of eggs, no matter what. The pigeon lays two eggs, if you take away the first, it will incubate the second egg only. If you add a third egg, it will incubate all three. But many other birds are indeterminate layers; they will continue to lay eggs until the nest is "full". If eggs are removed once they are laid, these birds will continue laying. When this subterfuge was used on a mallard female, she continued to lay one egg per day until she had laid 100 of them. Evidence from other, similar experiments suggests that most birds under normal circumstances do not lay their physiological limit of eggs but that ovulation is stopped long before this limit is reached.③The British ornithologist David Lack was one of the first ecologists to recognize the importance of evolutionary thinking in understanding adaptations in life history traits. In1947 Lack put forward the idea that clutch size in birds was determined by the number of young that parents can provide with food. If his hypothesis is correct, the total production of young ought to be highest at the normal clutch size. And if one experimentally increased clutch size by adding eggs to nests, increased clutches should suffer greater losses because the parents could not feed the extra young in the nest.④One way to think about this problem of optimum clutch size is to use a simple economic approach. Everything an organism does has some costs and some benefits. The benefits of laying more eggs are very clear--more descendants in the next generation. The costs are less clear. There is an energy cost to make each additional egg, and there is a further cost to feed each additional nestling. If the adult birds must work harder to feed their young, there is also a potential cost in adult survival -the adults may not live until the next breeding season. If adults are unable to work harder, there is a risk of reduction in offspring quality. Models of this type are useful because they help us think about the costs and benefits for a particular ecological strategy. No organism has an infiniteamount of energy to spend on its activities. The reproductive rate of birds can be viewed as one sector of a bird's energy balance, and the needs of reproduction must be maximized within the constraints of other energy requirements. The total requirements involve metabolic maintenance, growth, energy used for predator avoidance, competitive interactions, and reproduction. According to Lack's hypothesis, if enough additional eggs are placed in a bird's nest, reproductive energy requirements escalate and the whole brood will suffer from starvation so that, in fact, fewer young birds will fledge from nests containing large numbers ofeggs.⑤In England, the blue tit normally lays a clutch of nine to eleven eggs. What would happen if blue tits had a brood of twelve or thirteen? A researcher artificially manipulated broods at hatching by adding or subtracting chicks and found that the survival of the young blue tits in manipulated broods was poor. Blue tits feed on insects and apparently cannot feed additional young adequately, so more of the young starve. Consequently, it would not benefit a blue tit in the evolutionary sense to lay more eggs and the results areconsistent with Lack's hypothesis. Individual birds appear to produce the clutch size that maximizes their reproductive potential.译文鸟窝的大小①每年，皇帝企鹅会产下一枚蛋，鸽子会产下一颗或两颗蛋，海鸥通常会产下三颗蛋，加拿大鹅会产下四到六颗蛋，而美洲红颈潜鸭则会产下十到十一颗蛋。

智课网TOEFL备考资料托福TPO17综合写作精讲【动物类-鸟】摘要：有关动物类的文章也是我们托福考试过程中经常会遇到，托福TPO17综合写作部分的内容就设计到了这一块，下面我们就通过对托福TPO17综合写作内容的精讲，来为大家详细介绍一二，希望对大家会有一定的帮助。

托福 TPO17综合写作阅读材料：In the past century, the steady growth of the human population and the corresponding increasing in agriculture and pesticide use have caused much harm to wildlife in the United States – birds in particular. Unfortunately for birds, these trends are likely to continue, with the result that the number of birds in the United States will necessarily decline.在过去的一个世界，人类数量的增加以及随之而来的农业生产的发展和杀虫剂的增加使得很多美国的野生动物受到了影响，而这种问题在鸟类上表现得更为明显。

更加不幸的是，由于人口数量、农业生产和杀虫剂使用的趋势不会改变，美国的鸟类数量将会必然地随之下降。

First, as hu man populations and settlements continue to expand, birds ’ natural habitats will continue to disappear. Forests, wetlands, and grasslands will give way to ever more homes, malls,and offices. As the traditional areas suitable for birds keep decreasing, so will the size of the birds ’populations that depend on those vanishing habitats.首先，随着人口数量和居住面积的不断扩张，鸟类天然的栖息地持续地减少。

clutch size in birds托福阅读Clutch Size in BirdsClutch size refers to the number of eggs laid by a bird in a single nesting attempt. It is an important aspect of avian reproductive biology and can vary greatly among different bird species. The clutch size in birds is influenced by various factors, including environmental conditions, predation risk, and parental investment.One of the main factors affecting clutch size is the availability of resources. Birds living in environments with abundant food resources tend to have larger clutch sizes compared to those living in resource-poor habitats. This is because a larger clutch size increases the chances of at least some offspring surviving and successfully reproducing in environments with high resource availability.Predation risk also plays a significant role in determining clutch size. Birds nesting in areas with high predation risk, such as open habitats or near predator-rich areas, tend to have smaller clutch sizes. This is because smaller clutches allow parents to invest more time and energy into each individual offspring, increasing their chances of survival.Parental investment is another important factor influencing clutch size. In species where both parents contribute equally to incubation and chick-rearing, larger clutch sizes are more common. Thisis because both parents can share the workload and provide sufficient care for a larger number of offspring. On the other hand, species where only one parent provides most of the care tend to have smaller clutch sizes as it becomes more challenging for a single parent to raise multiple offspring.Furthermore, there are also trade-offs associated with clutch size. Larger clutches require more energy and resources from parents for incubation and feeding, which may result in reduced parental survival or future reproductive success. Therefore, there is often an optimal clutch size that maximizes the overall fitness of the parents. In conclusion, clutch size in birds is influenced by various factors including resource availability, predation risk, and parental investment. It serves as an important adaptation strategy for birds to maximize their reproductive success under different environmental conditions. Understanding the factors that influence clutch size can provide valuable insights into avian reproductive biology and help in conservation efforts for bird populations.。

clutch size in birds 托福阅读摘要：I.引言- 介绍鸟类的clutch size- 提出研究clutch size 对鸟类生活习性的影响II.鸟类clutch size 的定义和测量- 解释clutch size 是指鸟类一次繁殖中产下的蛋的数量- 描述测量clutch size 的方法，如统计鸟巢中的蛋的数量III.clutch size 对鸟类生活习性的影响- 分析clutch size 对鸟类繁殖成功率的影响- 讨论clutch size 对鸟类种群数量和分布的影响- 阐述clutch size 与鸟类体型、食物供应、气候等因素的关系IV.鸟类clutch size 的变化和适应性- 描述clutch size 在不同鸟类和不同环境中的变化- 探讨鸟类如何根据环境条件调整clutch size 以提高生存和繁殖机会V.人类活动对鸟类clutch size 的影响- 讨论人类活动（如捕猎、破坏栖息地等）对鸟类clutch size 的影响- 提出保护鸟类和其栖息地的措施，以维护鸟类clutch size 的稳定VI.结论- 总结clutch size 对鸟类生活习性的重要性- 强调保护鸟类及其栖息地的重要性正文：I.引言鸟类的生活习性千差万别，而其中一个有趣的方面就是它们的clutch size。

Clutch size 是指鸟类在一次繁殖过程中产下的蛋的数量。

对于鸟类来说，选择合适的clutch size 对其繁殖成功率和种群数量具有重要意义。

本文将详细探讨clutch size 对鸟类生活习性的影响，以及鸟类如何根据环境条件调整clutch size。

II.鸟类clutch size 的定义和测量Clutch size 是鸟类繁殖生物学中的一个重要概念，通常是指鸟类在一次繁殖过程中产下的蛋的数量。

在实际研究中，科学家们会通过统计鸟巢中的蛋的数量来测量clutch size。

clutch size in birds托福阅读托福阅读中有一个话题涉及到鸟类的抱窝大小（clutch size）。

抱窝大小是指在一次繁殖中，鸟类每次所产的蛋的数量。

鸟类种类繁多，其抱窝大小也因种类而异。

不同鸟类的抱窝大小差异很大，有些鸟类一次只产下一个蛋，而有些鸟类一次能产下几十个蛋。

抱窝大小受到多种因素的影响，其中包括鸟类的体型、饮食习惯以及栖息地的可用资源等。

首先，较小的鸟类通常产下较小的抱窝。

由于体型较小，它们需要更少的能量和营养来产卵，因此抱窝通常较小。

例如，金丝雀通常一次只会产下3到6个蛋，而鸽子一次会产下2个蛋。

其次，鸟类的饮食习惯也会影响到抱窝大小。

食物资源丰富的鸟类，比如鸽子和鸦科鸟类，一次可以产下几个蛋。

而食物稀缺的鸟类，比如雀科鸟类，在一次繁殖中通常只会产下一个蛋。

此外，栖息地的可用资源也会对抱窝大小产生影响。

在资源丰富的环境中，鸟类可以获得更多的食物和营养，因此能够产下更多的蛋。

而在资源匮乏的环境中，鸟类会因为食物短缺而减少产卵数量，以节省能量。

需要注意的是，鸟类的抱窝大小不仅受到外部因素的影响，还受到鸟类繁殖策略的调控。

有些鸟类采取单卵策略，即每次只产下一个蛋，这样可以确保孵化出的幼鸟能够得到充分的营养和抚育。

而有些鸟类采取多卵策略，一次产下多个蛋，这样增加了幼鸟的存活机会，因为即使有部分幼鸟未能成功孵化或成长，仍然有其他幼鸟可以存活下来。

总的来说，鸟类的抱窝大小受到多种因素的影响，包括鸟类的体型、饮食习惯以及栖息地的可用资源等。

了解鸟类的抱窝大小可以帮助我们更好地理解鸟类的生态习性和繁殖行为。

托福阅读真题第58篇TheMostCommonBirdonEarthThe red-billed quelea is small, mostly brown bird found in the annual grasslands of Africa. Other than ornithologists and the people who see the bird in its native habitat, almost no one has ever heard of the little quelea, although, with a population estimated at 10 billion, it may be the most common bird on Earth.Given the seemingly stressful conditions in the environments where the birds are found, it is surprising that the red-billed quelea survives at all, much less that it is so remarkably successful. Queleas feed on native annual grasses. Any animal that feeds primarily on the seeds of annual grasses has a potentially major problem-its food supply periodically appears and then disappears. A wide range of adaptations allows annual-seed eaters to survive. For example. rodents in annual grasslands often store their extra seeds to survive lean times, an adaptation that was taken up by human populations once they domesticated and became dependent on annual grasses, such as barley and wheat. If they are to survive, queleas must also cope with the challenging feast-or-famine situation attending annual-grass feeders. One might expect such species to be regularly wiped out (at least locally)when fluctuations in the growing season result in seed failures of their food. The red-billed quelea copes well enough to be the world's most common bird.Part of the quclea's success arisces from its life-history adjustments to its environment. Over the African dry scason, the species has to subsist on the ever-diminishing supply of seeds produced by the annual grasses at the end of the last wet season. As food becomes scarcer, the species feeds actively and gains sufficient weight reserves to be able to migrate to moreauspicious areas. With the onset of rains in the African wet season, the seeds that queleas eat germinate (develop) and so are no longer available for food. The resulting severe food shortage lasts six to eight weeks. The birds are forced to migrate to better situations (if they can find them). For red-billed qucleas, the savannas in which they live are an ever-shifting mosaic of patches of varying suitability depending on their recent rainfall history: some areas have dry seeds: others have immature grasses, mature grasses with abundant green seeds or old grasses with no seed. By moving over distances of 30 to 120 miles (50 to 200 km). the birds subsist in an inhospitable universe by moving from one patch of habitat with suitable food to another.The so-called early-rains migration ends when queleas return to formerly abandoned locations. By this time the rains have come and grass seeds have germinated. The new grasses mature, and eventually fresh green seeds become available. ending the local food shortage. Then queleas establish communal breeding colonies in appropriate locations. They typically nest in thorny acacia trees. Their breeding colonies can contain several million pairs of breeding birds and can cover tens of hectares. The entire breeding cycle, from nesting colony to independent fledged young, requires six weeks-an exceptionally short interval for birds. The biological synchrony found among the birds in a breeding colony can be remarkable. Millions of eggs in millions of nests hatch on the same day. The fall of eggshells from subsequent dropping of the shells from the nests after these synchronous hatchings has been likened to a snowstorm. Sometimes the dry season comes early and the breeding areas dry out prematurely. In such times, the breeding colonies are abandoned. In other instances, the rains may sustaina prolonged green period and several episodes of breeding can occur in the same general area.Since red-billed queleas feed on the seeds of annual grasses, they are preadapted to be effective feeders on the seeds of domesticated annual grasses as well. As human agriculture has planted more and more cereal grains across Africa, the numbers of quelea have exploded in response to the abundance of suitable food. The quelea's magnitude as pest animal has increased correspondingly. Although the numbers may be overestimated, the species is certainly capable of destroying 10 to 20 percent of the production of large farms and the entire crop of small, independent farmers. The red-billed quelea is not only the most abundant bird; it can also be described as the most destructive pest bird on Earth.1.The red-billed quelea is small, mostly brown bird found in the annual grasslands of Africa. Other than ornithologists and the people who see the bird in its native habitat, almost no one has ever heard of the little quelea, although, with a population estimated at 10 billion, it may be the most common bird on Earth.。