Heat exchanger analysis follows the same procedures as chemical reactor analysis with the added complication that we need to deal with two control volumes separated by a barrier of area a. As shown in Table 3.1 we need to consider both tank type and tubular systems and allow for mixed–mixed, mixed–plug, or plug–plug fluid motions.

A heat exchanger is any device in which energy in the form of heat is transferred. The types of heat exchangers in which we will be most interested are devices in which heat is transferred from a fluid at one temperature to another at a different temperature. This is most commonly done by the confinement of both fluids in some geometry in which they are separated by a conductive material. In such devices the area available for heat transfer is set by the device type and size, and is often the object of a design calculation. If the two fluids are immiscible it is possible to exchange heat by direct contact of one fluid with the other, but such direct contact heat exchange is somewhat unusual. It is, however, the configuration most commonly employed to transfer mass between two fluids, and as such, will be treated in detail in Chapter 4. Note that the area for heat (and mass) transfer is much more difficult to measure or calculate in direct fluid–fluid contacting.

A simple heat exchanger, easily constructed, is one in which the fluids are pumped through two pipes, one inside the other.

INTRODUCTION

Although the importance of accuracy in describing primary data cannot be overemphasized, this is only one of the steps in gathering data that are needed to interpret an assemblage. The ultimate goal is to relate animal remains to the other materials from the specific site and to other sites so that larger cultural and biological inferences can be made (Schmid 1972:7; Smith 1976). To make these larger inferences, it is often necessary to derive secondary data by estimating relative proportions or specific indices from the primary data. Secondary data, by their nature, are less descriptive and more subjective than primary data. Secondary data, often derived from primary data mathematically, summarize many primary observations and require explanation and interpretation. Disagreements about all aspects of secondary data are numerous.

The secondary data reviewed in this chapter are: estimates of body dimensions, construction of age classes and sex ratios, relative frequencies of taxa, skeletal frequencies, estimates of dietary contributions; modifications, and niche breadth. These are clearly interrelated and can be interpreted in terms of many different research questions either together or alone. Methods for deriving secondary data often are developed to pursue a specific research problem and may not be widely applied. Regional zooarchaeological traditions and the frequency with which specific methods appear in the literature are strongly correlated. The methods for deriving secondary data surveyed in this chapter are widely used and have broad applications.

When we were asked to prepare a second edition to Zooarchaeology, we anticipated that this would be relatively easy. We proposed to update the literature and work on sections that we or our colleagues found did not “work” in practice. We quickly realized, however, the truth of the statement that zooarchaeology is a dynamic field. We were surprised to find a few major changes in the traditional approaches in the field over the past 10 years and significant advances in archaeogenetic, isotopic, and incremental growth applications. A shift in research emphasis also has occurred. Whereas in 1999 many zooarchaeologists focused on biological and anthropological interpretations pertaining to economies and the history of animal domestication, today publications on environmental change, environmental reconstruction, and applied zooarchaeology constitute a large percentage of the literature. Advances in geochemical applications make it possible to develop holistic perspectives on the human–environment relationship, dissolving problematic distinctions among anthropology, archaeology, ecology, geology, human biology, and zoology. At the same time, after many years of functional interpretations, structural explanations have assumed a larger place in the literature. One of the most gratifying discoveries is the increase in important zooarchaeological studies published in peer-reviewed, international journals by scholars from beyond Europe and North America. This more broadly inclusive community of scholars is a good sign that zooarchaeology continues to be strongly international.

Thus, in preparing this second edition, we made major changes in sections in which the greatest advances have been made in the past decade.

INTRODUCTION

Zooarchaeology refers to the study of animal remains excavated from archaeological sites. The goal of zooarchaeology is to understand the relationship between humans and their environment(s), especially between humans and other animal populations. Zooarchaeology is characterized by its broad, interdisciplinary character, which makes it difficult to write a review that adequately covers all aspects of the field. This diversity can be traced to the application of many physical, biological, ecological, and anthropological concepts and methods to the study of animal remains throughout the world by scholars with a wide range of theoretical interests and training.

ZOOARCHAEOLOGY, AN INTERDISCIPLINARY FIELD

Although animal remains, especially fossils, have intrigued the human mind for centuries, the first critical examinations of these remains were not conducted until the 1700s. Since then, zooarchaeologists have relied on combinations of the natural and social sciences, history, and the humanities for concepts, methods, and explanations. By tradition, many studies focus on zoogeographical relationships, environmental evolution, and the impact of humans on the landscape from the perspective of animals. Many zooarchaeologists pursue anthropological interests in nutrition, resource use, economies, residential patterns, ritual, social identity, and other aspects of human life involving animals or parts of animals. All of these topics are encompassed within modern zooarchaeology.

Biological principles and topics are fundamental to zooarchaeology. Biological research includes exploration of extinctions and changes in zoogeographical distributions, morphological characteristics, population structure, the history of domestication, paleoenvironmental conditions, and ecological relationships of extant fauna using subfossil materials to provide historical perspective.

INTRODUCTION

Many aspects of zooarchaeology are associated with establishing a reference collection and with professional responsibilities regarding animal remains and data. Although the following comments are placed in an appendix, this does not mean they are minor aspects of zooarchaeology. Errors in handling animal remains create many of the second-order changes discussed in Chapter 5. These are avoidable biases, and steps should be taken to limit their occurrence. Many of the procedures associated with primary (Chapter 6) and secondary (Chapter 7) data are controversial and subsequent publications may not provide the details necessary for reanalysis. To clarify biases or resolve differences in interpretation, it may be necessary to review the original notes as well as both the studied and the unstudied portions of archaeofaunal assemblages.

An important development in archaeology is the growing awareness of the fragility of archaeological sites. No one should undertake excavation without a commitment to studying and curating all of the materials encountered. Excavation is destructive regardless of whether it is motivated by personal pleasure, economic profit, or a better understanding of the past. Although many of the following considerations are based largely on professional and ethical treatment of our natural and cultural heritage, increasingly they are governed by legal requirements as well. Most countries have laws governing the excavation of antiquities as well as their removal from the country of origin and importation into a second country. Within a country, many levels of administrative responsibility may exist.

INTRODUCTION

Developments in zooarchaeology over the past 50 years have transformed our knowledge of the associations between animals and people, and between them and other aspects of the environment. The field has grown from one in which a few biologists provided occasional identification services to one with full-time zooarchaeologists participating as regular members of interdisciplinary archaeological projects. Just as the number of professional zooarchaeologists has increased, so too has the number of laboratories with good reference collections. Progress is being made on all levels, from improved comprehension of site-formation processes to increased sophistication in research questions. We have a much better understanding of the diverse ways in which humans respond to the challenges and opportunities of their environments; the variety of roles that animals fill; the breadth of the animals' social meaning; the importance of cuisines in sustaining our biological and social lives; and the magnitude of our species' impact on the environment.

RELATIONSHIPS AMONG DATA AND INTERPRETATIONS

From the perspective of major anthropological and biological research questions, each of the seven types of primary data can be used to derive many interrelated types of secondary data (Table 11.1). For example, animal use is an important aspect of an economy, and animals fill other social roles. To study this, it is necessary to know which animals were used; how and where they were obtained; how individual animals or their products were distributed; how each animal contributed to the diet; whether skins and wool provided protection and warmth; how sinew, bone, teeth, and shell were fashioned into tools and ornaments; if animals provided traction, transport, or dung; and what was used and what was not used.

INTRODUCTION

Ecology is “the study of the natural environment, particularly the interrelationships between organisms and their surroundings” (Ricklefs 1973:11). Ecologists investigate where animals live, what they eat, when and where they find their food, when they breed, what groups they form, and what biotic and abiotic conditions are favorable for their successful existence. Hunters and fishermen have a wealth of such information obtained empirically and passed down to them from the accumulated knowledge of generations who applied this to procure the resources required for survival. The targeted species vary through time with changing technologies and consumption patterns. They also differ from place to place according to available fauna and regional cuisines. Reconstruction and analysis of past behavior relies on present-day knowledge of the ecology of the animals represented in archaeological contexts. Life history information about these animals may suggest where and when they were caught, and which capture methods were most successful.

Caution must be used in framing hypotheses about how hunting, trapping, collecting, and fishing was conducted. In the first place, archaeological concepts of time and space are different from ecological concepts (Grayson and Delpech 1998; Lyman 2003). Capture success must be measured in the context of the technology employed at a particular time and place. Given sufficient patience some fishes can be caught by hand, although we might think a net or spear would be required. Similarly, one would expect that capturing a large predator, such as a puma, would require a substantial weapon.

INTRODUCTION

The association between humans and domestic animals is one of the closest relationships existing among species. This relationship is considered to be mutualistic because both members benefit. Domestic animals owe their distinctive physical and behavioral characteristics, care, and feeding to the humans who control them. People, in turn, modify their own behavior and technology to manage the breed and provide for the biological needs of their domesticates. If success is measured by the numbers of offspring produced and consequent population increase, clearly the mutualistic relationship between humans and their major domesticated animals is a success (Rindos 1984).

The change from a hunting way of life to one incorporating animal husbandry was a profound one. Davis (1987:126) states that animal domestication “ranks in importance alongside the discovery of fire and tools.” Animal husbandry and plant cultivation are the foundations of modern civilization. The effect of domestication on animal and plant populations and on the environment has been, and continues to be, profound. It is not surprising that the origins of domestic animals, their wild progenitors, the region(s) where domestication took place, and the spread of animal husbandry, as well as cultural conditions that promoted these economic changes, are the focus of so much study (e.g., Davis 2005; Vigne et al. 2005).

Domestic animals have many characteristics by which we recognize them and that distinguish them from wild animals. The distinctive characteristics of domestic animals include conformation and variability, social behavior, and the contexts within which they occur.

INTRODUCTION

Archaeofaunal specimens offer unique opportunities for biological and anthropological inquiry, providing insights into the relationship between humans and their environments obtainable in no other way. However, first- and second-order changes alter the image of former lives available from faunal remains. Because some second-order changes develop during the process of gathering and analyzing data, thoughtful application of appropriate methods is important. A zooarchaeological study consists of three parts: (1) identification, (2) analysis, and (3) interpretation. Some of the methods used for identification are introduced in this chapter and are followed by analysis (Chapter 7), and interpretation (Chapters 8, 9, and 10). Important aspects of collection management, publication, and curation follow these chapters (see Appendix 3).

Clason's (1972) definitions of primary and secondary data distinguish between identification and analysis. The identification stage can be equated with collecting primary data and the analytical stage with deriving secondary data. Primary data are observations that can be replicated by subsequent investigators, such as element representation and taxonomic identification (e.g., Daly 1969; Lawrence 1973; Schmid 1972). Secondary data include age classes, sex ratios, relative frequencies of taxa, butchering patterns, dietary contributions, and procurement strategies. They are derived from primary data by means of indices and other quantification techniques. Primary data may be viewed as more descriptive and objective than secondary data and subject to less interpretive latitude. Using Lyman's (1994a) terminology, primary data are based on observational units or empirical manifestations and secondary data are analytical products.

INTRODUCTION

Research does not occur in an intellectual vacuum. When developing research designs, scholars should be familiar with both the history of their discipline and the current theoretical climate in the field in which they work. Zooarchaeology is such a diverse field that it is impossible to do justice to its history on a global scale; therefore, our emphasis is on zooarchaeology in the context of anthropological archaeology, primarily in the United States. Despite regional variations, it is surprising how similar zooarchaeology is internationally. This may result, in part, from international networks and the focus on animal remains. It may also be that the biological background of many zooarchaeologists and the relative youth of the field are responsible for the many shared features (Horton 1986). Nevertheless, it is important that students review literature from their study locale to learn about zooarchaeological trajectories in that specific area. Obituaries and dedicatory reviews are good sources of information about the field and collegial networks.

Zooarchaeological research has two related goals: (1) to understand, through time and space, the biology and ecology of animals, and (2) to understand the structure and function of human behavior. To address these goals, theories and methods are drawn from a number of sources. The biological and physical sciences are one source. The second source is anthropology, particularly those methods and theories pertaining to the relationship of humans with their natural and social environments. A third source is archaeology itself, especially where anthropology and archaeology are separate disciplines.

INTRODUCTION

The ecology of humans in respect to interactions with other species and the landscape, and the consequences to both humans and animals, are major themes in zooarchaeology. Human beings are both players promoting environmental change and spectators adjusting to changing environmental conditions. Habitats and specific animal populations thought to be pristine today, unmodified by human activities at any time in the past, may actually have had a substantial impact from human activities (e.g., Branch et al. 2005; Broughton 2004; Builth 2006; Mainland 2008; Mannino and Thomas 2001; Peacock 1998; Uchiyama 2006). Humans are not the only agents of environmental change. Environments may be altered by climate change, tectonic activity, tsunamis, plant and wildlife diseases, insects, storms, fires, and landslides, among the host of natural disasters that have an impact on ecosystems with or without human initiative.

Landscape changes initiated either by people (anthropogenic) or by so-called natural processes (nonanthropogenic) can be small or large, local or worldwide. Small changes, such as a storm or a path through the woods, may be elusive and hard to trace. However, the path may become a traditional trade route and ultimately a paved highway. Some human activities have an impact on huge areas or are global. For example, the Greenland ice sheet and Swedish lake sediments contain elevated levels of copper and lead that correlate with mining and smelting of these metals in the Roman Empire 2,000 years ago (Hong et al. 1994, 1996; Renberg et al. 1994).