2015年10月24日
托福阅读真题词汇题：
magnitude=size
stamina=endurance
ornament=decorated
deliberate=intentional
peak = the high point
authority=expert
aggregation=accumulation
presumably =supposedly
remarkable=extradinary
10月24日托福阅读真题第一篇 驯化物种
原文回顾： 古代人驯化物种，先说不同时代驯化的品种不同。最早的时候，人们驯养的都是狗，后来开始驯养羊，牛之类的，因为是从野生驯化的所以还存在很多问题。后来人们渐渐也知道了对于比较社会的那些动物首先驯服它们的领导者比较重要，还会把幼崽和父母分开驯养，让它们逐渐变得更驯养化。
相关背景学习：The Variation of Animals and Plants under Domestication
Darwin had been working for two years on his "big book" on Natural Selection, when on 18 June 1858 he received a parcel from Alfred Wallace, who was then living in Borneo. It enclosed a twenty pages manuscript describing an evolutionary mechanism that was similar to Darwin's own theory. Under pressure to publish his ideas, Darwin started work on an "abstract" trimmed from his Natural Selection which was published in November 1859 as On the Origin of Species. In the introduction he announced that in a future publication he hoped to give "in detail all the facts, with references, on which my conclusions have been grounded".
On 9 January 1860, two days after the publication of the second edition of Origin, Darwin returned to his original Natural Selection manuscript and began expanding the first two chapters on "Variation under Domestication". He had a large collection of additional notes and by the middle of June had written drafts of an introduction and two chapters on the domestication of pigeons that would eventually form part of The Variation of Animals and Plants under Domestication. Darwin apparently found writing the book tiresome and writes in his autobiography that he had been "tempted to publish on other subjects which at the time interested me more."[5] In the following July (1861) he began work on different book, the Fertilisation of Orchids which was published in May 1862.
Darwin continued to gather data. His own practical experiments were confined to plants but he was able to gather information from others by correspondence and even to arrange for some of his correspondents to conduct experiments on his behalf. In spite of protracted periods of illness, he made progress and in March 1865 wrote to his publisher, John Murray, saying that "Of present book I have 7 chapters ready for press & all others very forward, except the last & concluding one" (the book as finally published consisted of 28 chapters). In the same letter he discussed illustrations for the book.
Darwin had been mulling for many years on a theory of heredity. In May 1865 he sent a manuscript to his friend Thomas Huxley outlining his theory which he called pangenesis and asking whether he should publish it. In his accompanying letter Darwin wrote "It is a very rash & crude hypothesis yet it has been a considerable relief to my mind, & I can hang on it a good many groups of facts." Huxley pointed out the similarities of pangenesis to the theories of Georges Louis Leclerc, Comte de Buffon, and the Swiss naturalist Charles Bonnet but eventually wrote encouraging Darwin to publish: "Somebody rummaging among your papers half a century hence will find Pangenesis & say 'See this wonderful anticipation of our modern Theories—and that stupid ass, Huxley, prevented his publishing them'".
第二篇 暗礁
原文回顾：有一种暗礁很容易被摧毁，主要的方式是严重的风暴，还会受到飓风，或者是捕食者的影响。后来发现被摧毁很有可能是人类的原因，因为人类活动导致了植被移除，使得暗礁无法生存。
相关背景学习：Geologic reef
Geologists define reefs and related terms (for example, bioherm, biostrome, carbonate mound, pseudo-atoll) using the factors of depositional relief, internal structure, and biotic composition. There is no consensus on one universally applicable definition. A useful definition distinguishes reefs from mounds as follows. Both are considered to be varieties of organosedimentary buildups: sedimentary features, built by the interaction of organisms and their environment, that have synoptic relief and whose biotic composition differs from that found on and beneath the surrounding sea floor. Reefs are held up by a macroscopic skeletal framework. Coral reefs are an excellent example of this kind. Corals and calcareous algae grow on top of one another and form a three-dimensional framework that is modified in various ways by other organisms and inorganic processes. By contrast, mounds lack a macroscopic skeletal framework. Mounds are built by microorganisms or by organisms that don't grow a skeletal framework. A microbial mound might be built exclusively or primarily by cyanobacteria. Excellent examples of biostromes formed by cyanobacteria occur in the Great Salt Lake of Utah (USA), and in Shark Bay, Western Australia.
Cyanobacteria do not have skeletons and individuals are microscopic. Cyanobacteria encourage the precipitation or accumulation of calcium carbonate and can produce distinct sediment bodies in composition that have relief on the seafloor. Cyanobacterial mounds were most abundant before the evolution of shelly macroscopic organisms, but they still exist today (stromatolites are microbial mounds with a laminated internal structure). Bryozoans and crinoids, common contributors to marine sediments during the Mississippian (for example), produced a very different kind of mound. Bryozoans are small and the skeletons of crinoids disintegrate. However, bryozoan and crinoid meadows can persist over time and produce compositionally distinct bodies of sediment with depositional relief.
The Proterozoic Belt Supergroup contains evidence of possible microbial mat and dome structures similar to stromatolite reef complexes.
第三篇 鸟类的生物特征
原文回顾：雄性鸟普遍羽毛颜色比雌性的鸟鲜艳，比如火鸡，孔雀，因为它们需要竞争配偶。现在研究范围和领域已经先进了很多，看羽毛可以判断鸟是不是得了病。羽毛鲜艳还会引来捕食者的注意，所以它们比较强壮。
相关背景学习：Aerodynamics of wings
The design and analysis of the wings of aircraft is one of the principal applications of the science of aerodynamics, which is a branch of fluid mechanics. The properties of the airflow around any moving object can - in principle - be found by solving the Navier-Stokes equations of fluid dynamics. However, except for simple geometries these equations are notoriously difficult to solve.Fortunately, simpler explanations can be described.
For a wing to produce "lift", it must be oriented at a suitable angle of attack relative to the flow of air past the wing. When this occurs the wing deflects the airflow downwards, "turning" the air as it passes the wing. Since the wing exerts a force on the air to change its direction, the air must exert a force on the wing, equal in size but opposite in direction. This force manifests itself as differing air pressures at different points on the surface of the wing.
A region of lower-than-normal air pressure is generated over the top surface of the wing, with a higher pressure on the bottom of the wing. (See: airfoil) These air pressure differences can be either measured directly using instrumentation, or can be calculated from the airspeed distribution using basic physical principles—including Bernoulli's Principle, which relates changes in air speed to changes in air pressure.
The lower air pressure on the top of the wing generates a smaller downward force on the top of the wing than the upward force generated by the higher air pressure on the bottom of the wing. Hence, a net upward force acts on the wing. This force is called the "lift" generated by the wing.
The different velocities of the air passing by the wing, the air pressure differences, the change in direction of the airflow, and the lift on the wing are intrinsically one phenomenon. It is, therefore, possible to calculate lift from any of the other three. For example, the lift can be calculated from the pressure differences, or from different velocities of the air above and below the wing, or from the total momentum change of the deflected air. Fluid dynamics offers other approaches to solving these problems—and all produce the same answers if done correctly. Given a particular wing and its velocity through the air, debates over which mathematical approach is the most convenient to use can be mistaken by novices as differences of opinion about the basic principles of flight.
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