Pollution That Causes Acid Rain and Effects of Acid Rain

Acid rain is a general term for rain or other precipitation that has been polluted by chemicals called acids. This environmental problem can pollute lakes, rivers, and streams. It can damage metals and other construction materials. And it can even pose a health risk to people.

Acid rain forms when certain pollutants mix with tiny droplets of water vapor in the atmosphere. These pollutants include sulfur oxides and nitrogen oxides. Power plants are the main source of pollutants causing acid rain. Smoke from factories, exhaust fumes from automobiles and trucks, and even gases given off by chemical fertilizers also put pollutants into the air. The pollutants change the clean, fresh water to droplets of acid. These acids fall to the ground as rain, snow, or sleet. Even fog can contain acids.

Rain normally contains some naturally occurring acids. These are not considered a problem. However, sulfuric and nitric acids in rain are a problem. Acid rain soaks the ground and can make soil, lakes, and rivers abnormally acidic. In badly affected regions, plants and many types of aquatic animals are harmed. Entire lakes and some forest trees can be affected. Even buildings and statues can be damaged by acid rain.

Pollution That Causes Acid Rain

Pollutants such as sulfur oxides and nitrogen oxides enter the air when fossil fuels are burned. Fossil fuels include oil, coal, and gas. They are burned in industrial plants or automobile engines.

Nitrogen oxides and other acid-forming chemicals also enter the air from the breakdown of agricultural fertilizers. Hydrochloric acid often comes directly from smokestacks. Carbon monoxide and carbon dioxide are produced by motor vehicles.

Pollutants can travel over hundreds and even thousands of miles. As a result, acid rain often affects areas that are far from power plants and heavy automobile exhaust. Pollutants in smoke enter the air high above the ground through tall smokestacks. And they are carried by winds for great distances. Pollutants from the midwestern United States are regularly carried to New York, New England, and southeastern Canada. Similarly, pollution from Canada is carried by winds into the United States. Norway and Sweden have received acid rain created by pollutants from England, Germany, Italy, France, and Austria.

The Effects of Acid Rain

Millions of tons of acids fall in rain on the United States and Canada each year. The concentrations of these acids are too weak to cause burns. But they do produce other less severe effects.

When acid rain falls on metal objects, the objects can be damaged. Shiny objects become dull. If the process continues for many years, the metal objects can corrode and lose strength or crumble. Acid rain also affects the surfaces of stone statues and stone or brick buildings.

The way in which acid rain reacts with aluminum can cause serious ecological problems. Aluminum is normally present in soil. If acid rain causes soil acidification, the aluminum in the soil may dissolve in water. This aluminum may be absorbed by plants, where it can damage root cells. Animal cells are also very sensitive to aluminum. In lakes and streams, it can kill the eggs of many kinds of fish and the embryos of salamanders and other amphibians. Aluminum affects mature fish by causing the gills to clog with mucus. The fish cannot breathe. Aluminum also disrupts eggshell formation in birds.

Human beings may also be at risk from the effects of acid rain. In moist air, high levels of pollutants from acidic aerosols have been found to affect lung function in experimental studies. People who suffer from asthma, emphysema, and chronic bronchitis are more sensitive to acid environments.

Stopping Acid Rain

In 1990, the United States passed the Clean Air Act Amendments. This was a law that required significant annual reductions in air pollution. One measure to fight acid rain is to remove from the air those sulfur and nitrogen compounds that become acids. Some of these compounds can be taken out of fuel before the fuel is burned. Or the pollutants can be removed from smoke before the smoke enters the air. Each individual can also play a role in reducing air pollution by conserving energy. Individuals can cut back on the use of electricity, carpool, or use public transportation.

Language and Social Order

Language and Social Order

One of the most important goals of anthropology is to identify the range of possible forms of social organization in human societies. The study of language use is important in clarifying these and in showing how they are reproduced or overturned.

Even small and homogeneous communities exhibit internal linguistic diversity. The repertoires of ways of speaking found in Australian aboriginal groups include languages revealed only to initiates of secret societies, special forms for talking to in-laws, and extensive multilingualism. Edward Sapir reported that the Yana, a culture of Native American hunters and collectors in California, had special forms of speech for men and women. Like Sapir, contemporary linguistic anthropologists conclude that the unpredictable ways in which such differences are manifested cross-culturally means they have nothing to do with biological differences between the sexes. Speakers of Malagasy in Madagascar and Taiap in New Guinea believe that the extremes of rudeness and profanity appear in women's speech. This contrasts sharply with the assumption widely shared among English and Japanese speakers, for instance, that women are innately more polite than men.

When people speak, they tend to reveal and "reproduce" their social position, since the most important social differences within a community, such as gender, age, ethnicity, caste, and class, are usually reflected in language use. Dell Hymes has argued that differences in "communicative competence," the capacity to use effectively the language forms appropriate to a context, are a key source of inequalities in human communities. Exactly how a particular type of context will be made manifest can, however, be quite unpredictable in cross-cultural perspective. An excellent example is diversity in the way that social prestige is expressed. In the traditional African kingdom of Burundi, noble speech was valued for elegance and fluency, and people of low rank were expected to display their inferiority through clumsy speech. In contrast, among the Wolof of West Africa, fluency is the province of the low caste of griots. Nobles take care to stutter and make grammatical errors, and they employ griots to speak for them on occasions when eloquence is required.

Differences in ways of speaking may be an important clue to social differentiation that is covert or even denied. Thus in Mexican communities where both Spanish and Nahuatl, a Native American language, are spoken, members claim that they are all "farmers." However, differences in how speakers combine resources from the two languages (including the frequency of Spanish loanwords in speech considered to be in Nahuatl, and the way that these loanwords are pronounced) clearly distinguish people who make their living primarily from cultivation from those who are heavily involved in wage labor, and point to conflicts of interest between these two groups.

In addition to delineating social differences, language used effectively and appropriately can create the contexts in which efficacious interactions can move forward. For instance, among the Ilongot of the Philippines, traditional orators use highly indirect metaphorical speech to avoid offending political opponents. Through their expertise, "political arenas"—occasions when people gather to make decisions and negotiate disputes—can be constituted even though the authority to compel attendance is weak.

Almost any detail of linguistic form may be recruited to social purposes. The assignment of social meaning to differences in pronunciation is of course well known, but details of syntax may also have special social functions. In Samoan, a Polynesian language, the ergative case marks the agent of a transitive verb, contrasting with the absolute case, marking the subjects of intransitive verbs together with the objects of transitive verbs. In most languages that make this case distinction, its use is neutral in value, having only a grammatical function. In Samoan, however, the ergative case is generally avoided unless speakers are eager to assign blame or claim credit. Samoan children hardly use the ergative case marker at all because it is inappropriate for children to make value-laden judgments about responsibility.

Communication does not, of course, take place only among members of small communities. A research program originated by John Gumperz explores problems in cross-cultural communication, such as that between English speakers from India and England. Here, conflict may emerge partly because interactants, even though they are speaking the same language, do not share the same principles for interpreting conversational moves. Linguistic anthropologists have learned not to assume that the dominant ideologies about language and its use in any community will be universally accepted by its members. Much current research examines conflict stemming from resistance by subordinate groups against the linguistic values of elites. An excellent example is the language use encountered on "free radios" in the Basque region of Spain. By promiscuously mixing Basque and Spanish, and by using slangy and nonstandard forms of both languages, young people who run the illicit transmitters challenge the linguistic purism (and conformity to nationalist ideologies) of both Basque- and Spanish-speaking elites.

Language, Species, and Population

While quite complex symbolic abilities have been demonstrated in other animals, including at least the great apes and some birds, the capacity to acquire full human language is unique to Homo sapiens. Thus research on language is important for anthropologists who study human evolution. We do not know why language evolved, but since modifications of the organs of the vocal tract that apparently are required for human speech production detract from the efficiency of respiration, and cause an increased risk of choking on food (which can be fatal), the adaptive pressures in favor of full language must have been quite powerful. The phonetician Philip Lieberman has made the controversial suggestion that the anatomical structures required for modern human language do not appear in Neanderthals. If he is correct, full human language may be less than 40,000 years old.

The capacity for language can be manifested through gesture as well as speech, as in the sign languages of deaf communities, such as American Sign Language. Some scholars have argued that such gestural languages may predate oral forms in evolution. However, all human languages known today manifest the same evolutionary grade; no "primitive" languages have survived.

Boas and other founders of modern anthropology dismissed the possibility of a relationship between language and race. Because many people around the world are multilingual, and because abundant evidence exists from recent history of massive language shift (as in the spread of official national languages and the extinction of minority languages in Europe, or the acquisition of European languages by Native American groups and by Africans forced into slavery), it seems unlikely that any group defined as "all speakers of languages descended from a common ancestral tongue L" would match the group defined as "all human beings descended from a common ancestral biological population who spoke L." Recent highly controversial work has called this assumption into question. In collaboration with anthropological linguist Joseph Greenberg, human geneticists have suggested that there is a strong correlation between (1) phylogenetic groupings of languages at the highest level and (2) the large-scale, global distribution of genetic markers in human populations. If this finding is upheld, the study of historical linguistics will become an increasingly important tool for understanding the recent history of the human species.

However, many scholars doubt the validity of the methods used to establish phylogenetic groupings at the time depth claimed by Greenberg and other long-distance comparativists. Widely accepted historical linguistic techniques may be useful only for the very recent period, perhaps the last 8,000 to 10,000 years at most. Linguists often collaborate with archaeologists in the reconstruction of prehistory within this time depth. Research into the Bantu's expansion in Africa illustrates this type of collaboration. Bantu languages are spoken today over a very wide area in Central, East, and South Africa. Some scholars have argued that their spread was facilitated by the development of iron metallurgy in the proto-Bantu community. However, others challenged this view, claiming that a common word for iron can be reconstructed only for the Eastern Bantu. If this is true, the spread of the Bantu from a probable point of origin in the northwestern end of their range, in what today is the Cameroons, must have been made possible by some other technology, perhaps by an agricultural complex suited to the tropical forest environment, evidenced by proto-Bantu linguistic roots for "yam" and "oil palm," or by a marine technology that permitted the exploitation of tropical rivers, attested in proto-Bantu roots related to fishing and boating. The spread of iron technology into Central Africa would then be secondary and would come from the east. These claims yield models for archaeological interpretation.

Language, Culture and Thought

Major Questions

A central question of anthropology is whether, and how, different human cultures incline their members toward different understandings of the world. Investigation into the role of language in these understandings is a key project of linguistic anthropology.

Language, Culture, and Thought

For nearly 150 years a theoretical framework known as linguistic relativity dominated linguistics and, in turn, linguistic anthropology. This can be summarized as the idea that human languages are extremely diverse and that different languages may be organized according to locally distinctive principles. Wilhelm von Humboldt argued that these differences produced distinctive worldviews. Boas made significant contributions to this line of thought. His 1889 essay, "On Alternating Sounds," shows how speakers of one language, even when highly trained, often cannot accurately distinguish the sounds of another; their hearing is organized in terms of the sound system of the native tongue. In his 1911 "Introduction" to the Handbook of North American Indian Languages, Boas emphasized that the characteristic constructions of one language might pick out conceptual distinctions that were neglected in others. In a famous and often mischaracterized example, Boas pointed out that four Inuit words, aput ("snow on the ground"), qana ("falling snow"), piqsirpoq ("drifting snow"), and qimuqsuq ("a snowdrift"), share no common root. In English, in contrast, all these ideas require constructions incorporating the element snow. As Boas was not a linguistic determinist, he felt that a language such as that of the Inuit could easily develop an encoding for the more abstract notion of snow if the need arose.

Benjamin Whorf, a student of Sapir who was originally trained as an engineer, determined that relatively covert, yet far-reaching, patterns of co-occurrence between linguistic forms could strongly influence "habitual modes of thought and behavior" (as opposed to careful reflection). In one of his best-known illustrations of this point, he showed how European languages treat terms for units of time in the same way they treat terms for countable physical entities such as stones and dogs, which, unlike days or years, can be experienced by human beings in the form of several simultaneous exemplars. In contrast, in Hopi, a Native American language spoken in Arizona, terms for units of time do not accept plural affixation, and they occur only with ordinal numbers. Thus Hopi permits "the third day" but not "three days." Whorf argued that these patterns resonated in cultural manifestations such as European clocks and calendars, which stand for collections of units of time, and Hopi rituals that aim to regulate temporal succession and cyclicity. Since language, in Whorf's view, was the more intricately organized variable in this system of resonances, he felt that its structure shaped habitual forms of thought and behavior, rather than vice versa. That is, his position was a mild form of linguistic determinism.

Dell Hymes, a student of Carl F. Voegelin, who was a student of Sapir, argued in a 1966 paper for "two types of linguistic relativity": to the differences of form discussed by Whorf should be added differences of function. The functions assigned to varieties of a single language, or to several languages in a multilingual repertoire, may vary cross-culturally. Functional relativity can be illustrated by the question of how a speaker's native language marks community membership. For some speakers of the so-called standard languages of European national units, such as French and Castilian Spanish, competence in the standard is a central manifestation of nationality and, indeed, of patriotism itself. Such speakers may strongly oppose usages that depart from the official standard (such as giving children names in foreign languages or using foreign words on signboards) and may see cultivation of the national language as a logical function of government. In contrast, among highly multilingual Native American groups in the Upper Vaupes basin in Brazil and Colombia, one language in an individual's repertoire, the so-called father language, signals membership in the father's lineage. However, an individual must marry outside the group that claims this father language, and prestige lies not in conformity to it but in good control of a large number of languages within the local system.

Since the early 1960s the theory of relativity of linguistic form has faced sharp challenges. Hymes pointed out that a single language within the multilingual repertoire of a native of the Upper Vaupes would be unlikely to have important influence on that speaker's worldview. Anthropological linguist Joseph Greenberg identified many "language universals," ranging from limits on the possible arrays of distinctive sounds to limits on diversity in word order. Noam Chomsky, a formal theoretical linguist, argued that the language capacity must include a substantial genetic component and that the goal of linguistic science should be to identify the elements of this "universal grammar." Anthropological linguists Brent Berlin and Paul Kay showed that the apparent unwieldy diversity of color-term systems could be organized in terms of a very few fundamental principles, such that once the number of "basic color terms" in a language is known, the color domains that they designate can be largely predicted. For instance, systems with three terms will label a domain of darkness, centered in black; a domain of lightness, centered in white; and a domain of hue, centered in red. Systems with five terms will retain the black and white labels and will label three hue-based domains: one centered in yellow, a second centered in red, and a third domain of cool hues centered in blue or green.

Despite such challenges, research within a modified relativistic framework continues in linguistic anthropology alongside work on universals. Even though scholars now recognize that the diversity of languages is limited, many believe that local realizations of universal principles often yield "Whorfian effects": naive conclusions about the nature of the world suggested by the categories of a language. Research has shown that Whorfian effects appear very early in the speech of children and can be identified even in technical and scientific discourse. For instance, Berlin and Kay's basic color terms theory may depend on a language-specific fact: that these two scholars, as speakers of English, use a word, color, that refers to both brightness and hue. Many languages do not have such a term. Experimental studies conducted in the field show that speakers of English and Yucatec (a Mayan language of Mexico) respond differently to stimuli involving number and substance, in ways that correlate closely with differences in how the two languages treat these dimensions of experience. Speakers of Navajo—a language requiring that mention of more-animate referents (such as adult humans) always precedes the mention of less animate ones (such as animals) in transitive sentences (sentences that express the action of one entity on another)—understand the world to be organized as a complex hierarchy of types of entities that vary in their potential for motion, ranging from holy beings with the power to create the world to inert logs. Furthermore, the pragmatic and rhetorical dimensions of language, as well as poetic and artistic uses, are not constrained by the same kinds of universal principles that limit variation in sentence construction. These can focus and intensify experience, producing locally distinctive forms of cultural knowledge. For instance, the Kuna of Panama, in a chant for the magical control of dangerous snakes, exploit the contrast between the rhyming verbal suffixes -mai ("horizontal position") and -nai ("hanging position") to suggest how the magician controls the serpent by raising it from a horizontal position on the ground into the air, where it "hangs" under his power.

Linguistic,the Subfield of Anthropology

Anthropology, Linguistic,the subfield of anthropology that attends to the place of language in all its forms in the life of human communities, past and present. Many specialists today prefer the designation linguistic anthropology, but both terms are used.

History

The leading questions of linguistic anthropology can be traced at least to the period of the Enlightenment. Johann Gottfried von Herder, in his prizewinning "Essay on the Origin of Language" (1772), explored how language came to exist, the relationship between language and thought, and the relationship between language diversity and ethnic diversity. Enlightenment scholars collected linguistic materials from all over the world, as with the compilation made for Catherine the Great by Simon Pallas. The 1791 edition of this work contained information on 272 languages. Our understanding that the diversity of human languages results from the radiation of relatively few ancient languages into many descendant forms dates also to this era, to Sir William Jones's 1786 pronouncement that Sanskrit, Greek, and Latin were so similar that they must have "sprung from some common source" (the language known today as Proto-Indo-European).

In the early years of the 20th century, research on Native American languages shaped the discipline. The U.S. anthropologist Franz Boas argued that investigations into the structure of language could reveal the "fundamental ethnic ideas": basic understandings about the world that shape the development of human cultures and distinguish one from another. Edward Sapir, a prolific grammarian, wrote his dissertation on the Takelma language of Oregon under Boas's direction. The breadth of Sapir's interests, including the principles of linguistic structure, the history of languages and their speakers, the social organization of linguistic variation, and the relationship between language and thought, is taken by many linguistic anthropologists today as a charter for their field.

Reflecting on the magical spells used in gardening by the Trobriand Islanders of Melanesia, the Polish-born anthropologist Bronislaw Malinowski realized that their language was not merely a sign of thought but a "mode of action." In his first publication on this point, in 1921, Malinowski argued that this was characteristic of "primitive" languages, but in Coral Gardens and Their Magic (1935), he moved to the position held by Boas and Sapir, that there are no primitive languages. Instead, language exhibits these functions in all human communities. European linguists of the Prague School focused in the 1920s and 1930s on the functional relationships between language and society, including language standardization and the development of literary language. One leader of the Prague circle, the Russian linguist Roman Jakobson, fled Europe for the United States in 1941, and his functionalist perspective became a major influence on American linguistic anthropology.

Methodology

Boas insisted on firsthand contact with speakers of languages, rather than the compilation of materials collected by travelers and missionaries. Both Boas and Sapir worked directly with speakers of Native American languages, often in remote communities. They devised writing systems for these languages and trained native-speaker consultants to use them, making these local experts partners in data collection. Such collaborations foreshadowed our current understanding of field research, as a dialogue between investigators from two traditions, not a one-way extraction of data by a knowing scholar from a "naive" informant. Boas, believing that the principles of a culture were fully revealed only in the local language, placed heavy emphasis on the collection of textual materials, ranging from myth cycles to recipes. While Boas, Sapir, and their students recorded language data writing on wax cylinders and wire, advances in recording technology now permit linguistic materials to be inexpensively recorded on audio or videotape, played back in the field for discussion with speakers, and archived as permanent evidence of findings. Ease of recording facilitates the use of survey methods that draw on large samples of speakers rather than on only a few key consultants. It also permits full exploitation of the ethnographic method of participant observation. Early scholars of necessity depended heavily on interviews, structured by principles emanating from the home culture of the anthropologist, not from the culture of the consultant. Portable recorders permit investigators to record language use during events that are part of the ordinary life of the community, such as rituals, legal proceedings, and interactions between caretakers and children. The ability to manipulate such recordings makes possible very fine-grained discourse analysis, now widely used by linguistic and cultural anthropologists to explore subtle details of interactional dynamics, emotional disposition, and the organization of cultural knowledge.

Fieldwork today is strongly influenced by the "ethnography of speaking," a program initiated in the 1960s by Dell H. Hymes and John Gumperz. This framework approaches the forms and uses of language as a part of culture, just like food production or religious practice, and equally susceptible to ethnographic study. An ethnographer of speaking should identify the full range of linguistic patterns and occasions and their use by the group under study, from everyday conversation to theatrical performances, philosophical discourse, and all forms of written language. Research should ideally address all languages spoken in a multilingual community, and deal with the full range of competencies among speakers.