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Micro-wear patterns found on the teeth of long-extinct specimens of the primate species australopithecine may provide evidence about their diets. For example, on the basis of tooth micro-wear patterns, Walker dismisses Jolly's hypothesis that australopithecines ate hard seeds. He also disputes Szalay's suggestion that the heavy enamel of australopithecine teeth is an adaptation to bone crunching, since both seed cracking and bone crunching produce distinctive micro-wear characteristics on teeth. His conclusion that australopithecines were frugivores (fruit eaters) is based upon his observation that the tooth micro-wear characteristics of east African australopithecine specimens are indistinguishable from those of chimpanzees and orangutans, which are commonly assumed to be frugivorous primates.However, research on the diets of contemporary primates suggests that micro-wear studies may have limited utility in determining the foods that are actually eaten. For example, insect eating, which can cause distinct micro-wear patterns, would not cause much tooth abrasion in modern baboons, who eat only soft-bodied insects rather than hard-bodied insects. In addition, the diets of current omnivorous primates vary considerably depending on the environments that different groups within a primate species inhabit; if australopithecines were omnivores too, we might expect to find considerable population variation in their tooth micro-wear patterns. Thus, Walker's description of possible australopithecine diets may need to be expanded to include a much more diverse diet.
Historians have identified two dominant currents in the Russian women's movement of the late tsarist period. "Bourgeois" feminism, so called by its more radical opponents, emphasized "individualist" feminist goals such as access to education, career opportunities, and legal equality. "Socialist" feminists, by contrast, emphasized class, rather than gender, as the principal source of women's inequality and oppression, and socialist revolution, not legal reform, as the only road to emancipation and equality.However, despite antagonism between bourgeois feminists and socialist feminists, the two movements shared certain underlying beliefs. Both regarded paid labor as the principal means by which women might attain emancipation: participation in the workplace and economic self-sufficiency, they believed, would make women socially useful and therefore deserving of equality with men. Both groups also recognized the enormous difficulties women faced when they combined paid labor with motherhood. In fact, at the First All-Russian Women's Congress in 1908, most participants advocated maternity insurance and paid maternity leave, although the intense hostility between some socialists and bourgeois feminists at the Congress made it difficult for them to recognize these areas of agreement. Finally, socialist feminists and most bourgeois feminists concurred in subordinating women's emancipation to what they considered the more important goal of liberating the entire Russian population from political oppression, economic backwardness, and social injustice.
Planter-legislators of the post-Civil War southern United States enacted crop lien laws stipulating that those who advanced cash or supplies necessary to plant a crop would receive, as security, a claim, or lien, on the crop produced. In doing so, planters, most of whom were former slaveholders, sought access to credit from merchants and control over nominally free laborers--former slaves freed by the victory of the northern Union over the southern Confederacy in the United States Civil War. They hoped to reassure merchants that despite the emancipation of the slaves, planters would produce crops and pay debts. Planters planned to use their supply credit to control their workers, former slaves who were without money to rent land or buy supplies. Planters imagined continuation of the pre-Civil War economic hierarchy: merchants supplying landlords, landlords supplying laborers, and laborers producing crops from which their scant wages and planters' profits would come, allowing planters to repay advances. Lien laws frequently had unintended consequences, however, thwarting the planter fantasy of mastery without slavery. The newly freed workers, seeking to become self-employed tenant farmers rather than wage laborers, made direct arrangements with merchants for supplies. Lien laws, the centerpiece of a system designed to create a dependent labor force, became the means for workers, with alternative means of supply advances, to escape that dependence.
In Forces of Production, David Noble examines the transformation of the machine-tool industry as the industry moved from reliance on skilled artisans to automation. Noble writes from a Marxist perspective, and his central argument is that management, in its decisions to automate, conspired against labor: the power that the skilled machinists wielded in the industry was intolerable to management. Noble fails to substantiate this claim, although his argument is impressive when he applies the Marxist concept of "de-skilling" —— the use of technology to replace skilled labor —— to the automation of the machine-tool industry. In automating, the industry moved to computer-based, digitalized "numerical control" (N/C) technology, rather than to artisan generated "record-playback" (R/P) technology.Although both systems reduced reliance on skilled labor, Noble clearly prefers R/P, with its inherent acknowledgment of workers` skills: unlike N/C, its programs were produced not by engineers at their computers, but by skilled machinists, who recorded their own movements to "teach" machines to duplicate those movements. However, Noble's only evidence of conspiracy is that, although the two approaches were roughly equal in technical merit, management chose N/C. From this he concludes that automation is undertaken not because efficiency demands it or scientific advances allow it. but because it is a tool in the ceaseless war of capitalists against labor.
C13

     The stock market tends to move in response to the monthly release of the U.S. consumer confidence index (CCI), signaling that individuals make investment decisions on the basis of this information. Such behavior is mostly irrational. The CCI is generally understood to be a lagging indicator; by the time the CCI has been released, the stock market should have already reflected the latest adjustments to its prices based on consumer sentiment. Furthermore, the CCI, to the degree that it reflects on the stock market, reflects only on the stock market as a whole, not on individual stocks. The questions that make up the CCI, indeed, gauge individual levels of confidence about factors, such as employment rates, that should have little direct bearing on most individual stocks relative to other factors. To dampen the influence of the CCI on the stock market, the Conference Board, the nonprofit group that reveals the information each month, should adjust its timetable in order to publish the CCI outside of stock market hours. In that case, the impact of the CCI on stock market prices would be smoothed and would be more likely to reflect individual investors' business estimates, rather than their animal whims.    
Micro-wear patterns found on the teeth of longextinct specimens of the primate species australopithecine may provide evidence about their diets. For example, on the basis of tooth micro-wea patterns, Walker dismisses Jolly's hypothesis that australopithecines ate hard seeds. He also disputes Szalay's suggestion that the heavy enamel of australopithecine teeth is an adaptation to bone crunching, since both seed cracking and bone crunching produce distinctive micro-wear characteristics on teeth. His conclusion that australopithecines were frugivores (fruit eaters) is based upon his observation that the tooth micro- wear characteristics of east African australopithecine specimens are indistinguishable from those of chimpanzees and orangutans, which are commonly assumed to be frugivorous primatesHowever, research on the diets of contemporary primates suggests that micro-wear studies may have limited utility in determining the foods that are actually eaten. For example, insect eating, which can cause distinct micro-wear patterns, would not cause much tooth abrasion in modern baboons, who eat only soft-bodied insects rather than hard-bodied insects. In addition, the diets of current omnivorous primates vary considerably depending on the environments that different groups within a primate species inhabit; if australopithecines were omnivores too, we might expect to find considerable population variation in their tooth micro-wear patterns. Thus, Walker's description of possible australopithecine diets may need to be expanded to include a much more diverse diet.
Ready4 To determine whether one species blocks another out of an area, one approach is to infer assembly rules, which reconstruct the sequence in which species were added to an evolving community. For example, the presence of a plant species might support the establishment of a beetle that feeds on the plant, and a wasp that in turn parasitizes the beetle. Each of these species, like a puzzle piece, might block the entry of some competing species into the community. But whether a species holds an exclusive functional place cannot easily be identified by studying a community as an isolated unit; local communities are not isolated assemblages and are better thought of as members of a metacommunity of linked smaller ecosystems. Consequently, observing the existence of two functionally similar species in a particular community could reflect that there is room for both species in the assembly or that they really belong to what are mostly distinct, neighboring communities. For example, in a particular brackish coastal lagoon, the species scophtalmus rhombus and solea solea are not only both fish, but have comparable functional traits such as eye diameters, caudal fin aspect ratios, and length-to-body-depth ratios. This functional similarity could imply mutual exclusivity, but another possibility is that scophtalmus rhombus and solea solea occupy positions in the same community within the lagoon, perhaps because food is abundant or because they are less functionally similar than they appear; another is that they occupy exclusive positions in neighboring communities within that lagoon or the mouth of that lagoon to the coastal seas, and the fact that they have been found near each other reflects an exception rather than the rule.
Ready4

     The stock market tends to move in response to the monthly release of the U.S. consumer confidence index (CCI), signaling that individuals make investment decisions on the basis of this information. Such behavior is mostly irrational. The CCI is generally understood to be a lagging indicator; by the time the CCI has been released, the stock market should have already reflected the latest adjustments to its prices based on consumer sentiment. Furthermore, the CCI, to the degree that it reflects on the stock market, reflects only on the stock market as a whole, not on individual stocks. The questions that make up the CCI, indeed, gauge individual levels of confidence about factors, such as employment rates, that should have little direct bearing on most individual stocks relative to other factors. To dampen the influence of the CCI on the stock market, the Conference Board, the nonprofit group that reveals the information each month, should adjust its timetable in order to publish the CCI outside of stock market hours. In that case, the impact of the CCI on stock market prices would be smoothed and would be more likely to reflect individual investors' business estimates, rather than their animal whims.    
The dry mountain ranges of the Western United States contain rocks dating back 440 to 510 million years, Line to the Ordovician period, and teeming with evidence of tropical marine life.This rock record provides clues about one of the most significant radiations (periods when existing life-forms gave rise to variations that would eventually) evolve into entirely new species) in the history of marine invertebrates. During this radiation the number of marine biological families increased greatly, and these families included species that would dominate the marine ecosystems of the area for the next 215 million years. Although the radiation spanned tens of millions of years, major changes in many species occurred during a geologically short time span within the radiation and, furthermore, appear to have occurred worldwide, suggesting that external events were major factors in the radiation. And, in fact, there is evidence of major ecological and geological changes during this period: the sea level dropped drastically and mountain ranges were formed, in this instance, rather than leading to large-scale extinctions, these kinds of environmental changes may have resulted in an enriched pattern of habitats and nutrients, which in turn gave rise to the Ordovician radiation, However, the actual relationship between these environmental factors and the diversification of life forms is not yet fully understood
The system of patent-granting, which confers temporary monopolies for the exploitation of new technologies, was originally established as an incentive to the pursuit of risky new ideas. Yet studies of the most patent-conscious business of all—the semi-conductor industry—suggest that firms do not necessarily become more innovative as they increase their patenting activity. Ziedonis and Hall, for example, found that investment in research and development (a reasonable proxy for innovation) did not substantially increase between 1982 and 1992, the industry's most feverish period of patenting. Instead, semiconductor firms simply squeezed more patents out of existing research and development expenditures. Moreover, Ziedonis and Hall found that as patenting activity at semiconductor firms increased in the 1980's, the consensus among industry employees was that the average quality of their firms' patents declined. Though patent quality is a difficult notion to measure, the number of times a patent is cited in the technical literature is a reasonable yardstick, and citations per semiconductor patent did decline during the 1980's. This decline in quality may be related to changes in the way semi-conductor firms managed their patenting process: rather than patenting to win exclusive rights to a valuable new technology, patents were filed more for strategic purposes, to be used as bargaining chips to ward off infringement suites or as a means to block competitors' products.
More selective than most chemical pesticides in that they ordinarily destroy only unwanted species, biocontrol agents (such as insects, fungi, and viruses) eat, infect, or parasitize targeted plant or animal pests. However, biocontrol agents can negatively affect nontarget species by, for example, competing with them for resources: a biocontrol agent might reduce the benefits conferred by a desirable animal species by consuming a plant on which the animal prefers to lay its eggs.[hl:6]Another example of indirect negative consequences occurred in England when a virus introduced to control rabbits reduced the amount of open ground (because large rabbit populations reduce the ground cover), in turn reducing underground ant nests and triggering the extinction of a [hl:3]blue butterfly[/hl:3] that had depended on the nests to shelter its offspring.[/hl:6] The paucity of known extinctions or disruptions resulting from indirect interactions may reflect not the infrequency of such mishaps but rather the failure to look for or to detect them: most organisms likely to be adversely affected by indirect interactions are of little or no known commercial value and the events linking a biocontrol agent with an adverse effect are often unclear. Moreover, determining the potential risks of biocontrol agents before they are used is difficult, especially when a nonnative agent is introduced, because, unlike a chemical pesticide, a biocontrol agent may adapt in unpredictable ways, so that it can feed on or otherwise harm new hosts.
Conodonts, the spiky phosphatic remains (bones and teeth composed of calcium phosphate) of tiny marine animals that probably appeared about 520 million years ago, were once among the most controversial of fossils. Both the nature of the organism to which the remains belonged and the function of the remains were unknown. However, since the 1981 discovery of fossils preserving not just the phosphatic elements but also other remains of the tiny soft-bodied animals (also called conodonts) that bore them, scientists' reconstructions of the animals' anatomy have had important implications for hypotheses concerning the development of the vertebrate skeleton.The vertebrate skeleton had traditionally been regarded as a defensive development, champions of this view postulating that it was only with the much later evolution of jaws that vertebrates became predators. The first vertebrates, which were soft bodied, would have been easy prey for numerous invertebrate carnivores, especially if these early vertebrates were sedentary suspension feeders. Thus, traditionalists argued, these animals developed coverings of bony scales or plates, and teeth were secondary features, adapted from the protective bony scales. Indeed, external skeletons of this type are common among the well-known fossils of ostracoderms, jawless vertebrates that existed from approximately 500 to 400 million years ago. However, other paleontologists argued that many of the definitive characteristics of vertebrates, such as paired eyes and muscular and skeletal adaptations for active life, would not have evolved unless the first vertebrates were predatory. Teeth were more primitive than external armor according to this view, and the earliest vertebrates were predators.The stiffening notochord along the back of the body, V-shaped muscle blocks along the sides, and posterior tail fins help to identify conodonts as among the most primitive of vertebrates. The lack of any mineralized structures apart from the elements in the mouth indicates that conodonts were more primitive than the armored jawless fishes such as the ostracoderms. It now appears that the hard parts that first evolved in the mouth of an animal improved its efficiency as a predator, and that aggression rather than protection was the driving force behind the origin of the vertebrate skeleton.
(This passage was excerpted from material published in 1993.)Like many other industries, the travel industry is under increasing pressure to expand globally in orderto keep pace with its corporate customers, who have globalized their operations in response to market pressure, competitor actions, and changing supplier relations. But it is difficult for service organizations to globalize. Global expansion through acquisition is usually expensive, and expansion through internal growth is time-consuming and sometimes impossible in markets that are not actively growing. Some service industry companies, in fact, regard these traditional routes to global expansion as inappropriate for service industries because of their special need to preserve local responsiveness through local presence and expertise. One travel agency has eschewed the traditional route altogether. A survivor of the changes that swept the travel industry as a result of the deregulation of the airlines in 1978 — changes that included dramatic growth in the corporate demand for travel services, as well as extensive restructuring and consolidation within the travel industry - this agency adopted a unique structure for globalization. Rather than expand by attempting to develop its own offices abroad, which would require the devel- opment of local travel management expertise sufficient to capture foreign markets, the company solved its globalization dilemma effectively by forging alliances with the best foreign partners it could find. The resulting cooperative alliance of independent agencies now comprises 32 partners spanning 37 countries.
In the fourteenth and fifteenth centuries, many Western Pueblo settlements in what is now the southwestern United States may have possessed distinctly hierarchical organizational structures. These communities' agricultural systems-which were "intensive" in the use of labor rather than "extensive" in area-may have given rise to political leadership that managed both labor and food resources. That formal management of food resources was needed is suggested by the large size of [hl:2]storage spaces[/hl:2] located around some communal Great Kivas (underground ceremonial chambers). Though no direct evidence exists that such spaces were used to store food, Western Pueblo communities lacking sufficient arable land to support their populations could have preserved the necessary extra food, including imported foodstuffs, in such apparently communal spaces.Moreover, evidence of specialization in producing raw materials and in manufacturing ceramics and textiles indicates differentiation of labor within and between communities. The organizational and managerial demands of such specialization strengthen the possibility that a decision-making elite existed, an elite whose control over labor, the use of community surpluses, and the acquisition of imported goods would have led to a concentration of economic resources in their own hands. [hl:1]Evidence for differential distribution of wealth is found in burials of the period: some include large quantities of pottery, jewelry, and other artifacts, whereas others from the same sites lack any such materials.[/hl:1]
In a new book about the antiparty feeling of the early political leaders of the United States, Ralph Ketcham argues that the first six Presidents differed decisively from later Presidents because the first six held values inherited from the classical humanist tradition of eighteenth-century England. In this view, government was designed not to satisfy the private desires of the people but to make them better citizens; this tradition stressed the disinterested devotion of political leaders to the public good. Justice, wisdom, and courage were more important qualities in a leader than the ability to organize voters and win elections. Indeed, leaders were supposed to be called to office rather than to run for office. And if they took up the burdens of public office with a sense of duty, leaders also believed that such offices were naturally their due because of their social preeminence or their contributions to the country. Given this classical conception of leadership, it is not surprising that the first six Presidents condemned political parties. Parties were partial by definition, self-interested, and therefore serving something other than the transcendent public good.Even during the first presidency (Washington's), however, the classical conception of virtuous leadership was being undermined by commercial forces that had been gathering since at least the beginning of the eighteenth century. Commerce--its profit-making, its self-interestedness, its individualism--became the enemy of these classical ideals. Although Ketcham does not picture the struggle in quite this way, he does rightly see Jackson's tenure (the seventh presidency) as the culmination of the acceptance of party, commerce, and individualism. For the Jacksonians, nonpartisanship lost its relevance, and under the direction of Van Buren, party gained a new legitimacy. The classical ideals of the first six Presidents became identified with a privileged aristocracy, an aristocracy that had to be overcome in order to allow competition between opposing political interests. Ketcham is so strongly committed to justifying the classical ideals, however, that he underestimates the advantages of their decline. For example, the classical conception of leadership was incompatible with our modern notion of the freedoms of speech and press, freedoms intimately associated with the legitimacy of opposing political parties.
After the Second World War, unionism in the Japanese auto industry was company-based, with separate unions in each auto company. Most company unions played no independent role in bargaining shop-floor issues or pressing autoworkers' grievances. In a 1981 survey, for example, fewer than 1 percent of workers said they sought union assistance for work-related problems, while 43 percent said they turned to management instead. There was little to distinguish the two in any case: most union officers were foremen or middle-level managers, and the union's role was primarily one of passive support for company goals. Conflict occasionally disrupted this cooperative relationship--one company union's opposition to the productivity campaigns of the early 1980s has been cited as such a case. In 1986, however, a caucus led by the Foreman's Association forced the union's leadership out of office and returned the union's policy to one of passive cooperation. In the United States, the potential for such company unionism grew after 1979, but it had difficulty taking hold in the auto industry, where a single union represented workers from all companies, particularly since federal law prohibited foremen from joining or leading industrial unions.The Japanese model was often invoked as one in which authority decentralized to the shop floor empowered production workers to make key decisions. What these claims failed to recognize was that the actual delegation of authority was to the foreman, not the workers. The foreman exercised discretion over job assignments, training, transfers, and promotions; worker initiative was limited to suggestions that fine-tuned a management-controlled production process. Rather than being proactive, Japanese workers were forced to be reactive, the range of their responsibilities being far wider than their span of control. For example, the founder of one production system, Taichi Ohno, routinely gave department managers only 90 percent of the resources needed for production. As soon as workers could meet production goals without working overtime, 10 percent of remaining resources would be removed. Because the "OH! NO!" system continually pushed the production process to the verge of breakdown in an effort to find the minimum resource requirement, critics described it as "management by stress."
In a 1918 editorial, W.E.B. Du Bois advised African Americans to stop agitating for equality and to proclaim their solidarity with White Americans for the duration of the First World War. The editorial surprised many African Americans who viewed Du Bois as an uncompromising African American leader and a chief opponent of the accommodationist tactics urged by Booker, T.Washington. In fact, however, Du Bois often shifted positions along the continuum between Washington and confrontationists such as William Trotter. In 1895, when Washington called on African Americans to concentrate on improving their communities instead of opposing discrimination and agitating for political rights, Du Bois praised Washington's speech. In 1903, however, Du Bois aligned himself with Trotter, Washington's militant opponent, less for ideological reasons than because Trotter had described to him Washington's efforts to silence those in the African American press who opposed Washington's positions.Du Bois's wartime position thus reflected not a change in his long-term goals but rather a pragmatic response in the face of social pressure: government officials had threatened African American journalists with censorship if they continued to voice grievances. Furthermore, Du Bois believed that African Americans' contributions to past war efforts had brought them some legal and political advances. Du Bois' accommodationism did not last, however. Upon learning of systematic discrimination experienced by African Americans in the military, he called on them to "return fighting" from the war.
In a 1918 editorial,W.E.B. Du Bois advised African Americans to stop agitating for equality and to proclaim their solidarity with White Americans for the duration of the First World War. The editorial surprised many African Americans who viewed Du Bois as an uncompromising African American leader and a chief opponent of the accommodationist tactics urged by Booker T. Washington. In fact, however, Du Bois often shifted positions along the continuum between Washington and confrontationists such as William Trotter. In 1895, when Washington called on African Americans to concentrate on improving their communities instead of opposing discrimination and agitating for political rights, Du Bois praised Washington's speech. In 1903, however, Du Bois aligned himself with Trotter, Washington's militant opponent, less for ideological reasons than because Trotter had described to him Washington's efforts to silence those in the African American press who opposed Washington's positions. Du Bois's wartime position thus reflected not a change in his long-term goals but rather a pragmatic response in the face of social pressures: government officials had threatened African American journalists with censorship if they continued to voice grievances. Furthermore, Du Bois believed that African Americans' contributions to past war efforts had brought them some legal and political advances. Du Bois's accommodationism did not last, however. Upon learning of systematic discrimination experiencedby African Americans in the military, he called on them to "return fighting"from the war.
In a 1918 editorial, W.E.B. Du Bois advised African Americans to stop agitating for equality and to proclaim their solidarity with White Americans for the duration of the First World War. The editorial surprised many African Americans who viewed Du Bois as an uncompromising African American leader and a chief opponent of the accommodationist tactics urged by Booker, T.Washington. In fact, however, Du Bois often shifted positions along the continuum between Washington and confrontationists such as William Trotter. In 1895, when Washington called on African Americans to concentrate on improving their communities instead of opposing discrimination and agitating for political rights, Du Bois praised Washington's speech. In 1903, however, Du Bois aligned himself with Trotter, Washington's militant opponent, less for ideological reasons than because Trotter had described to him Washington's efforts to silence those in the African American press who opposed Washington's positions.Du Bois's wartime position thus reflected not a change in his long-term goals but rather a pragmatic response in the face of social pressure: government officials had threatened African American journalists with censorship if they continued to voice grievances. Furthermore, Du Bois believed that African Americans' contributions to past war efforts had brought them some legal and political advances. Du Bois' accommodationism did not last, however. Upon learning of systematic discrimination experienced by African Americans in the military, he called on them to "return fighting" from the war.
All the cells in a particular plant start out with the same complement of genes. How then can these cells differentiate and form structures as different as roots, stems, leaves, and fruits? The answer is that only a small subset of the genes in a particular kind of cell are expressed, or turned on, at a given time. This is accomplished by a complex system of chemical messengers that in plants include hormones and other regulatory molecules. Five major hormones have been identified: auxin, abscisic acid, cytokinin, ethylene, and gibberellin. Studies of plants have now identified a new class of regulatory molecules called oligosaccharins.Unlike the oligosaccharins, the five well-known plant hormones are pleiotropic rather than specific; that is, each has more than one effect on the growth and development of plants. The five have so many simultaneous effects that they are not very useful in artificially controlling the growth of crops. Auxin, for instance, stimulates the rate of cell elongation, causes shoots to grow up and roots to grow down, and inhibits the growth of lateral shoots. Auxin also causes the plant to develop a vascular system, to form lateral roots, and to produce ethylene.The pleiotropy of the five well-studied plant hormones is somewhat analogous to that of certain hormones in animals. For example, hormones from the hypothalamus in the brain stimulate the anterior lobe of the pituitary gland to synthesize and release many different hormones, one of which stimulates the release of hormones from the adrenal cortex. These hormones have specific effects on target organs all over the body. One hormone stimulates the thyroid gland, for example, another the ovarian follicle cells, and so forth. In other words, there is a hierarchy of hormones.Such a hierarchy may also exist in plants. Oligosaccharins are fragments of the cell wall released by enzymes: different enzymes release different oligosaccharins. There are indications that pleiotropic plant hormones may actually function by activating the enzymes that release these other, more specific chemical messengers from the cell wall.