해커스 GRE 버벌 송종옥 선생님의 특급 자료

Lichens consist of a fungus and an alga living in symbiotic union. Testing the widely held hypothesis that lichen-forming fungi are a closely knit, peripheral group of fungi, a team of scientists compared DNA sequences from 10 lichen-forming and 65 non-lichen-forming fungus species. These scientists classified the lichen forming fungi into five kinds that were more closely related to kinds of non-lichen-forming fungi than to one another. The closest relatives of the lichen-forming kinds included some fungi that benefit, and others that cause disease to, associated organisms. Therefore, lichen-forming fungi probably evolved from various species whose effects on associated organisms ranged from benign to malignant. Furthermore, lichen-forming fungi seem to have given rise to other fungi that act as harmful parasites on lichens themselves. These considerations undermine the long-standing hypothesis that symbiotic relationships normally evolve in an orderly progression from those that are harmful to one partner to those that are mutually beneficial.

Researchers suspect that meteorites (particles of matter that fall to Earth’ s surface from space) are pieces of asteroids, the many minor planets primarily inhabiting the region between Mars and Jupiter called the asteroid belt. The most common meteorites are ordinary chondrites-rocks containing tiny flecks of metal. By analyzing the spectrums of sunlight reflected by asteroids to determine the asteroids’ chemical composition, researchers have found that most of the brighter asteroids contain the same silicates and other compounds that dominate chondrites. These silicaceous, or S-type, asteroids are the most abundant type in the inner asteroid belt, the part of the asteroid belt from which objects are most likely to escape and travel to Earth. However, S-type asteroids reflect red and infrared light much better than they reflect green, blue, and violet light, suggesting that they have a higher metal content than do ordinary chondrites. This has led at least one researcher to posit that meteorites come from other types of asteroids that are too small and too dim to be detected. However, S-type asteroids could be ordinary chondrites that have been weathered by the effects of the space environment, making them seem redder and more metallic than they really are.

The first phase of English literature can be described as ending with the Protestant Reformation, which radically changed English culture. Though the literature produced before the Reformation varied markedly, a consistency is often apparent: it was grounded in the Latin Christianity that dominated Western Europe from the early Middle Ages to the sixteenth century. The Christian Church, however, had taken form in the midst of the powerful pagan cultures of ancient Greece and Rome, and the later Roman and lrish missionaries to England planted the Church in the midst of still another pagan culture, that of the ancient Germanic peoples who inhabited England. Oddly enough, the new religion scorned neither the literary tradition of Greco-Roman paganism nor that of Germanic paqanism. Aldhelm, the first English poet who wrote in Latin, and Caedmon, the first to use English, were contemporaries, and each sang the praises of the Christian God in an artistic medium inherited from paganism.

For two decades after the Civil War, the political cartoons of Thomas Nast remained the most recognizable visual feature of Harper’s Weekly , at the time one of the most widely circulated magazines in the United States. But despite his considerable fame, his dominance over the pictorial content of a successful periodical, and his unprecedented salary among American illustrators, Nast often felt beleaguered and disgruntled at Harper’s Weekly. At the end of 1886, after nearly quitting on several earlier occasions, he declined to renew his contract with his publishers. Writers on Nast have commonly blamed his dissatisfaction and waning influence at the firm upon political feuding with the management, allegedly an increasingly conservative group reluctant to tolerate Nast’s radical, reformist views. But this ubiquitous explanation greatly exaggerates any such political rift while ignoring a crucial shift in cultural attitudes towards heightened civility in mainstream journalism that did far more to fuel resentments between the artist and his editorial board. Nast’s alienation from his longtime employer stemmed less from divergent political goals and more from differing approaches to the niceties of political debate, most notably his failure to adapt his distinctly violent cartoons to standards of decorum embraced by his publishing house during the 1870s.

Researchers who study human foraging have found that while hunters and fishers choose the resource areas (patches) with the highest mean profitability most frequently, they do not exploit these patches exclusively. A possible explanation for this finding might be daily variation in environmental conditions, such as prey movements and weather conditions. If such daily fluctuations do not equally impact the profitability of patches across a habitat, the most profitable patch on average may not be the most profitable patch every day. A study of Ifaluk fishers revealed that they pursue alternative lower-ranked patches when the returns on that morning or the previous day from the highest-ranked patch are lower than those typically available from alternative patches.

Glaciologists have conjectured that increasing temperatures and decreasing precipitation caused the rapid observed retreat of glaciers throughout the European Alps after the mid-nineteenth century. However, such scenarios are inconsistent with temperature records and climate proxies. During the latter half of the nineteenth century through the early twentieth century, when glaciers were retreating rapidly, temperatures in the Alpine region were apparently cooler than in the late eighteenth to early nineteenth centuries, and precipitation was largely unchanged. Glaciers subject to these climatic conditions alone should have advanced instead of retreated. One possible explanation is the dramatic rise of industrial black carbon in the mid-nineteenth century. Black carbon deposits could have increased the absorption of solar radiation by snow, generally increasing glacier melt and resulting in glacier retreat.

Kacelnik proposed that birds sing more at dawn and dusk because low light levels make feeding relatively unprofitable. Colder temperatures also make prey less active and thus harder to find. So why do birds wake up before they can feed, and why don’t they wake up much earlier to lengthen the dawn chorus? It may be that other birds are unresponsive until only shortly before foraging becomes possible. Birds could listen to mates or neighbors singing overnight, but much social behavior contingent on that signal might plausibly occur only when there is some light. Such social interactions–like chasing intruders or mating—could be performed effectively at light levels at which foraging is still inefficient.

As the United States shifted from an agricultural, production-oriented economy to an urban, bureaucratized, consumer-oriented economy, children were removed from the labor force and valued for sentimental rather than instrumental reasons. Children were increasingly studied, regulated, and protected through the rise of pediatrics, child psychology, child-welfare agencies, compulsory schooling, child-study programs, and so-called scientific parenting regimes. These changes shifted public attention away from the child considered to be in need of saving and toward the kind of child whose development would preoccupy parents, and whom advertisers would showcase—and eventually appeal to directly—in their promotion of goods. The redefinition of childhood served not to separate children from the commercial realm, but, rather, to advance the commoditization of childhood and the broader transformation to a consumer economy.

A central question in comparative politics is whether or not the state is necessary, a question that can be answered empirically in the negative on the evidence that some societies have no state. Stateless societies, however, are characterized by political processes; for that reason they can be said to share to a more or less degree some of the features of states. A more useful and accurate assertion than the empirical is that “stateness” is a quality that prevails in more or less quantity or intensity in all human communities. If one is concerned with the values of security, material well-being, the maintenance of social order, and risk-sharing, one must conclude that more stateness is better than less. On the other hand, when one is concerned with equality, freedom, justice, and self-esteem, one concludes that less stateness is better than more. Certainly none of these values can be discussed intelligibly without some degree of assumption of stateness.