inevitable = unavoidableadj. 不可避免的
oversee = supervisev. 监督
surpass = exceedv. 超过
drastic = extremeadj. 极端的、剧烈的
aggregation = groupn. 聚集体、集合
designation = identificationn.名称、身份
lateral adj. 侧面的、横向的
capacity n. 能力、容量
observev. 观察
catch up with the pace of跟上……的步伐
第一篇
版本一：关于眼睛的起源
版本二：第一篇眼睛起源 不是来自多细胞动物 早起软体动物化石提供证据
版本三：讲生物眼睛的构造和进化什么的
解析：本文关注眼睛的起源，重复的是2012年8月19日阅读。该文属于起源类别文章，通过考古证据提出理论，在TPO里类似的文章非常多，自然科学类和社会科学类均涉及，在理解时重点关注不同的证据支持的观点，以及后续证据对前观点的支持或反驳。
参考阅读：
The common origin (monophyly) of all animal eyes is now widely accepted as fact. This is based upon the shared genetic features of all eyes; that is, all modern eyes, varied as they are, have their origins in a proto-eye believed to have evolved some 540 million years ago, and the PAX6 gene is considered a key factor in this. The majority of the advancements in early eyes are believed to have taken only a few million years to develop, since the first predator to gain true imaging would have touched off an "arms race" among all species that did not flee the photopic environment. Prey animals and competing predators alike would be at a distinct disadvantage without such capabilities and would be less likely to survive and reproduce. Hence multiple eye types and subtypes developed in parallel (except those of groups, such as the vertebrates, that were only forced into the photopic environment at a late stage).
Eyes in various animals show adaptation to their requirements. For example, birds of prey have much greater visual acuity than humans, and some can detect ultraviolet radiation. The different forms of eye in, for example, vertebrates and molluscs are examples of parallel evolution, despite their distant common ancestry. Phenotypic convergence of the geometry of cephalopod and most vertebrate eyes creates the impression that the vertebrate eye evolved from an imaging cephalopod eye, but this is not the case, as the reversed roles of their respective ciliary and rhabdomeric opsin classes and different lens crystallins show.
The very earliest "eyes", called eyespots, were simple patches of photoreceptor protein in unicellular animals. In multicellular beings, multicellular eyespots evolved, physically similar to the receptor patches for taste and smell. These eyespots could only sense ambient brightness: they could distinguish light and dark, but not the direction of the light source.
Through gradual change, the eyespots of species living in well-lit environments depressed into a shallow "cup" shape, the ability to slightly discriminate directional brightness was achieved by using the angle at which the light hit certain cells to identify the source. The pit deepened over time, the opening diminished in size, and the number of photoreceptor cells increased, forming an effective pinhole camera that was capable of dimly distinguishing shapes. However, the ancestors of modern hagfish, thought to be the protovertebrate were evidently pushed to very deep, dark waters, where they were less vulnerable to sighted predators, and where it is advantageous to have a convex eye-spot, which gathers more light than a flat or concave one. This would have led to a somewhat different evolutionary trajectory for the vertebrate eye than for other animal eyes.
The thin overgrowth of transparent cells over the eye's aperture, originally formed to prevent damage to the eyespot, allowed the segregated contents of the eye chamber to specialise into a transparent humour that optimised colour filtering, blocked harmful radiation, improved the eye's refractive index, and allowed functionality outside of water. The transparent protective cells eventually split into two layers, with circulatory fluid in between that allowed wider viewing angles and greater imaging resolution, and the thickness of the transparent layer gradually increased, in most species with the transparent crystallin protein.
The gap between tissue layers naturally formed a bioconvex shape, an optimally ideal structure for a normal refractive index. Independently, a transparent layer and a nontransparent layer split forward from the lens: the cornea and iris. Separation of the forward layer again formed a humour, the aqueous humour. This increased refractive power and again eased circulatory problems. Formation of a nontransparent ring allowed more blood vessels, more circulation, and larger eye sizes.
第二篇
版本一：原始 社会男女各自司职的变化 以前原始女人地位高 因为他们负责种田收获务实 后来工具发明后男人地位比女人高 女人只能生产副产品 比如养牛羊 织布 带孩子
版本二：性别作用和地位在农业发展中的变化
版本三：农业发展对男女角色分工和的影响 从女人务农到男耕女织
解析：本文属于因果型文章，侧重点在影响，涉及到男女分工在农业发展中的变化，背景知识不难，在理解时重点提取产生的影响体现在什么方面，假设是否成立。
参考阅读：
The gender division of labor varies significantly across societies. In particular, there are large differences in the extent to which women participate in activities outside of the home. For instance, in 2000, the share of women aged 15 to 64 in the labor force ranged from a low of 16.1% in Pakistan to 90.5% in Burundi.
A number of scholars have argued that these differences reflect differences in underlying cultural values and beliefs. Consistent with this, data on self-reported values about gender confirm that countries with lower female labor force participation also have stronger beliefs of gender inequality. However, this culture-based explanation still leaves unanswered the deeper question of why cultural differences exist in the first place.
One hypothesis, initially proposed by Ester Boserup (1970), is that the origin of these differences lies in the different types of agriculture traditionally practiced across societies. In particular, she highlights important differences between shifting agriculture and plough agriculture. Shifting agriculture, which uses hand-held tools like the hoe and the digging stick, is labor-intensive with women actively participating in farm work. By contrast, plough agriculture is more capital-intensive, using the plough to prepare the soil. Unlike the hoe or digging stick, the plough requires significant upper body strength, grip strength, and bursts of power, which are needed to either pull the plough or control the animal that pulls it. As well, farming with the plough is less compatible with simultaneous childcare, which is almost always the responsibility of women. As a result, men tended to specialize in agricultural work outside the home.
Within plough agriculture societies, centuries of a gender-based division of labor created a cultural belief that it is more natural for men to work outside the home than women. These cultural beliefs then continue to persist even after the economy transitions from agriculture to industry and services. Through this cultural channel, traditional agriculture affects the participation of women in activities performed outside of the home today.
第三篇
版本一：是19世纪欧洲人口数量的增长和农业的关系吧貌似。
版本二：食物供给变好了导致了工业革命欧洲人口的上升
版本三：19世纪欧洲人口变化的因素和城市化发展
解析：从话题来看重复的是2013年7月13日北美阅读。本文同第二篇，属于因果型文章，侧重点在原因，背景知识也是常考的历史发展类背景，理解时需要额外关注的是历史类文章句子偏难，在定位到答案后要小心断句，仔细理解，避免误选。同第二篇，理解时的重点是提取给定的原因及原因发挥的作用。
参考阅读：
After a century of virtually no population growth, the countries of Western Europe experienced dramatic population increases between 1750 and 1800. Many countries doubled in size. In some countries, the growth continued through the nineteenth century. The population of Great Britain, for instance, doubled between 1750 and 1800 and then tripled between 1800 and 1900.
There were several reasons for the sudden increase. Medical advances and improved hygiene limited the devastation caused by epidemic diseases and plagues. The introduction of new food crops, most notably the potato, provided a better diet for the poor and reduced the incidence of famine. The combination of greater public order and fewer civil wars meant that life was less hazardous. The net result was a lower death rate and soaring populations.
The growing population, with a rising proportion of children to raise and older people to care for, put increased pressure on every aspect of society. Many peasants were no longer able to provide land for their children, who were forced to look for other ways to make their living. Small artisans in the cities suffered similar problems, unable to provide places for their children in their own workshops.
The exact relationship between population growth and industrialization is unclear, though the two are clearly intertwined. (Even countries that were late to industrialize shared in the general population increase, and its related problems.) What is clear is that the growth in population increased the demand for both food and manufactured goods and provided an abundance of cheap labor to produce them.