Over the last 150 years, large stretches of salmon habitat have been eliminated by human activity: mining, livestock grazing, timber harvesting, and agriculture as well as recreational and urban development. The numerical effect is obvious: there are fewer salmon in degraded regions than in pristine ones; however, habitat loss also has the potential to reduce genetic diversity. This is most evident in cases where it results in the extinction of entire salmon populations. Indeed, most analysts believe that some kind of environmental degradation underlies the demise of many extinct salmon populations. Although some rivers have been recolonized, the unique genes of the original populations have been lost.

    Large-scale disturbances in one locale also have the potential to alter the genetic structure of populations in neighboring areas, even if those areas have pristine habitats. Why? Although the homing instinct of salmon to their natal stream is strong, a fraction of the fish returning from the sea(rarely more than 15 percent) stray and spawn in nearby streams. Low levels of straying are crucial, since the process provides a source of novel genes and a mechanism by which a location can be repopulated should the fish there disappear. Yet high rates of straying can be problematic because misdirected fish may interbreed with the existing stock to such a degree that any local adaptations that are present become diluted. Straying rates remain relatively low when environmental conditions are stable, but can increase dramatically when streams suffer severe disturbance. The 1980 volcanic eruption of Mount Saint Helens, for example, sent mud and debris into several tributaries of the Columbia River. For the next couple of years, steelhead trout (a species included among the salmonids) returning from the sea to spawn were forced to find alternative streams. As a consequence, their rates of straying, initially 16 percent, rose to more than 40 percent overall.

    Although no one has quantified changes in the rate of straying as a result of the disturbances caused by humans, there is no reason to suspect that the effect would be qualitatively different than what was seen in the aftermath of the Mount Saint Helens eruption. Such a dramatic increase in straying from damaged areas to more pristine streams results in substantial gene flow, which can in turn lower the overall fitness of subsequent generations.

Line	Linda Kerber argued in the mid-1980s that after
	the American Revolution (1775–1783), an ideology
	of “republican motherhood” resulted in a surge of
	educational opportunities for women in the United
(5)	States. Kerber maintained that the leaders of
	the new nation wanted women to be educated in
	order to raise politically virtuous sons. A virtuous
	citizenry was considered essential to the success
	of the country's republican form of government;
(10)	virtue was to be instilled not only by churches and
	schools, but by families, where the mother's role
	was crucial. Thus, according to Kerber, motherhood
	became pivotal to the fate of the republic, providing
	justification for an unprecedented attention to female
(15)	education.
	Introduction of the “republican motherhood”
	thesis dramatically changed historiography. Prior
	to Kerber's work, educational historians barely
	mentioned women and girls; Thomas Woody's
(20)	1929 work is the notable exception. Examining
	newspaper advertisements for academies, Woody
	found that educational opportunities increased for
	both girls and boys around 1750. Pointing to “An
	Essay on Woman” (1753) as reflecting a shift in
(25)	view, Woody also claimed that practical education
	for females had many advocates before the
	Revolution. Woody's evidence challenges the notion
	that the Revolution changed attitudes regarding
	female education, although it may have accelerated
(30)	earlier trends. Historians’ reliance on Kerber's
	“republican motherhood” thesis may have obscured
	the presence of these trends, making it difficult
	to determine to what extent the Revolution really
	changed women's lives.

    A pressing need in the study of organizations is for more research into how an organization's values (anLine organization's guiding principles and beliefs as perceived by its members) affect managerial decision-making. Traditional theories have been based on a "rational model," which focuses on the decision-maker and either ignores the organizational value climate or conveniently assumes that the organization's values are consistent or clearly prioritized. In reality, however, decisions are shaped not only by a manager's own values, but also by those of the corporate culture and of organizational superiors. A recent study found that managers' most stressful decisions involved "valuecontention" (conflicts among any of these sets of values). Furthermore, different types of organizational value systems were associated with different frequencies of contending values as well as with different types of managerial response. Explicit corporate values, for example, produced a greater percentage of decisions that were stressful due to value contention. Hidden values (those that an organization practices but does not acknowledge or which a superior furtively pursues in opposition to the values of the organization) produced a lower level of value contention. Although explicit values created more value contention, they were nonetheless more likely to produce flexible, well-reasoned decisions. Conversely, managers perplexed by hidden values reported feeling unable to identify an appropriate range of options.