The problem: Answer a question about this article:
In the 11th century, the Seljuk Turks took over much of the Middle East, occupying Persia during the 1040s, Armenia in the 1060s, and Jerusalem in 1070. In 1071, the Turkish army defeated the Byzantine army at the Battle of Manzikert and captured the Byzantine Emperor Romanus IV (r. 106871). The Turks were then free to invade Asia Minor, which dealt a dangerous blow to the Byzantine Empire by seizing a large part of its population and its economic heartland. Although the Byzantines regrouped and recovered somewhat, they never fully regained Asia Minor and were often on the defensive. The Turks also had difficulties, losing control of Jerusalem to the Fatimids of Egypt and suffering from a series of internal civil wars. The Byzantines also faced a revived Bulgaria, which in the late 12th and 13th centuries spread throughout the Balkans.
Who conquered Jerusalem from the Turks?
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The answer: the Fatimids of Egypt

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Perhaps the most prominent, controversial and far-reaching theory in all of science has been the theory of evolution by natural selection put forward by the British naturalist Charles Darwin in his book On the Origin of Species in 1859. Darwin proposed that the features of all living things, including humans, were shaped by natural processes over long periods of time. The theory of evolution in its current form affects almost all areas of biology. Implications of evolution on fields outside of pure science have led to both opposition and support from different parts of society, and profoundly influenced the popular understanding of "man's place in the universe". In the early 20th century, the study of heredity became a major investigation after the rediscovery in 1900 of the laws of inheritance developed by the Moravian monk Gregor Mendel in 1866. Mendel's laws provided the beginnings of the study of genetics, which became a major field of research for both scientific and industrial research. By 1953, James D. Watson, Francis Crick and Maurice Wilkins clarified the basic structure of DNA, the genetic material for expressing life in all its forms. In the late 20th century, the possibilities of genetic engineering became practical for the first time, and a massive international effort began in 1990 to map out an entire human genome (the Human Genome Project).
What was the major break through for the study of genetics?
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The answer: the basic structure of DNA

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The history of Academies in France during the Enlightenment begins with the Academy of Science, founded in 1635 in Paris. It was closely tied to the French state, acting as an extension of a government seriously lacking in scientists. It helped promote and organize new disciplines, and it trained new scientists. It also contributed to the enhancement of scientists' social status, considering them to be the "most useful of all citizens". Academies demonstrate the rising interest in science along with its increasing secularization, as evidenced by the small number of clerics who were members (13 percent). The presence of the French academies in the public sphere cannot be attributed to their membership; although the majority of their members were bourgeois, the exclusive institution was only open to elite Parisian scholars. They perceived themselves as "interpreters of the sciences for the people". For example, it was with this in mind that academicians took it upon themselves to disprove the popular pseudo-science of mesmerism.
Members of what group were considered to be the "most useful of all citizens?"
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The answer: scientists

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External evidence is evidence of each physical witness, its date, source, and relationship to other known witnesses. Critics will often prefer the readings supported by the oldest witnesses. Since errors tend to accumulate, older manuscripts should have fewer errors. Readings supported by a majority of witnesses are also usually preferred, since these are less likely to reflect accidents or individual biases. For the same reasons, the most geographically diverse witnesses are preferred. Some manuscripts show evidence that particular care was taken in their composition, for example, by including alternative readings in their margins, demonstrating that more than one prior copy (exemplar) was consulted in producing the current one. Other factors being equal, these are the best witnesses. The role of the textual critic is necessary when these basic criteria are in conflict. For instance, there will typically be fewer early copies, and a larger number of later copies. The textual critic will attempt to balance these criteria, to determine the original text.
Why are older manuscripts preferred?
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The answer:
Since errors tend to accumulate, older manuscripts should have fewer errors.