Defining Physical Anthropology

Note: These materials are intended as supplements for students in Ant. 301. These pages are in development and will contain errors.

DEFINING PHYSICAL ANTHROPOLOGY

What Are Humans?

What Is Anthropology?

Culture

The Subdiscipline of Physical Anthropology

Biological Continuity

Anthropological Perspective

Science as a Way of Understanding

Summary

Questions for Review

Further Reading

DEFINING PHYSICAL ANTHROPOLOGY

The fundamental questions addressed by physical anthropologists are "What does it mean to be human?" and "How did we become human?" We will draw upon data from many fields to provide scientific answers to those questions. The nature of the scientific process is that it continuously refines our ideas with new information and new insights that add to their accuracy. Although the general features of these answers have been firmly established for half a century, there is still much to debate and much to learn. It is an exciting, challenging process, and perhaps the ultimate intelligence test for our species is to understand ourselves.

Two concepts provide the fundamental tools to understand the history of our species and our planet. The first concept - uniformitarianism, the idea that the physical processes that shape our landscape today and the biological processes that shape our lives are the same forces that operated in the past- offers a possibility that if we study and understand these processes, we may gain insights about events of the past and the magnitude of time they represent. The second concept is biological continuity, the thread of descent that connects all life. When living beings reproduce, they do not create life -- they pass it along.

What Are Humans?

Modern humans belong to a single species that exhibits considerable variation in behavior, size, shape, and appearance. In modern usage, humans belong to the species Homo sapiens Linnaeus 1758, a name coined by an 18th century botanist, Carl Linnaeus. (Note that the year and the originator are part of the name.) For purposes of nomenclature (classification) he placed Homo sapiens with the anatomically similar apes, monkeys, and lemurs into a group that he called Primates. In modern view, the Order Primates is retained as the mammalian group that contains humans and their nearest nonhuman relatives.

What Is Anthropology?

Anthropology is the scientific study of the origin, behavior, physical variation, and cultural development of human beings. It embraces the whole of humanity, past and present. Contemporary anthropology in the United States is generally divided into four broad categories that loosely describe the subjects that are treated, rather than their theoretical perspective:

(1) Physical anthropology, also known as bioanthropology, is the anthropological study of human biology, particularly its origins, diversity, and adaptations. In order to place humans in a comparative perspective, physical anthropologists also study the origins and biology of the Primates, the group of mammals that includes humans and our closest nonhuman relatives. Physical anthropology diverges from other disciplines of biology by its focus.

(2) Archeology, the study of cultural variation over time, focuses on artifacts, constructions, or other evidence of human activities. Its techniques are used to investigate prehistory, or to provide physical evidence of contemporary events such as locating historical structures. Archeological techniques of excavation and documentation are also sometimes used to recover evidence from a crime scene. The terms bioarchaeologist and zooarchaeologist identify specialists who deal with human or other animal bones from archaeological sites.

(3) Linguistics studies human communication systems. Its topics range from language to the dynamics of human interaction.

(4) Cultural anthropology is study of human behavior, especially human culture. Culture encompasses the patterns of learned behavior and thought that are characteristic of members of a society and are not the result of biological inheritance. This learning includes languages, knowledge, beliefs, morals, laws, customs, kinship systems, values, art, and folklore.

Anthropology as an academic tradition in the United States is holistic. That is, it pays attention to a society as a functioning whole. Humanity is a very diverse and adaptable species, and no matter what one's special interest, anthropologists try to relate the process or subject of their study to a broader framework of what it means to be human. The broad scope of anthropology also makes it a convenient discipline to house social scientists who study anthropological subjects but not necessarily from an anthropological perspective.

Culture

As children, we perceive the world around us, and we learn language from other people. We must learn which sounds, images, and material things are meaningful in order to use sounds and images in the process of living and communicating. Along with learning language, we learn the organization of our world. We learn what to expect from people and what others expect us to do. We are punished when we misbehave and rewarded when we achieve. We also learn "why, how, and when." We learn correlations between events and situations. Thus, when our childhood training is complete, we carry "blueprints" in our head that organize perceptions, control thinking, predict behavior, and motivate us, similar to the ways genes control processes of cells within our body.

These blueprints, meanings of sounds, images, material things, value systems, and organization of perceptions, are summed up in the idea of "culture." Anthropology is the comparative study of humans as physical and cultural beings. It is holistic, and its aim is to understand the human animal and its place in the natural order of things. The common focus of anthropology that separates it from other academic disciplines, is culture. Anthropologists study the forms of culture, the cultural processes, the biological basis for culture, and the human body. A biological anthropologist brings the full conceptual framework of biology to the study of humanity.

It is important to distinguish between "culture" and "a culture." Whereas "culture" refers to the general history, processes and abilities that allow humans to acquire patterned, repetitive ways of perceiving, thinking, feeling and acting, "a culture" is the actual blueprint held by a particular group of people. One can thus refer to the "Navaho culture" or the "Bushman culture." One can also refer to the ability of a human to acquire "culture." Once scientists realized that other animals, particularly the nonhuman primates, also have complex learned traditions, another term, protoculture, was coined to refer to these behaviors in nonhumans

Since our culture shapes the way we understand biology, culture becomes doubly important. One's own view of the environment is continually simplified and generalized. We constantly impose our own constructions and meanings on our surroundings. For simplicity, we call the constructions and meanings that characterize our culture our world view. A world view is a major feature of human biology, shaping how we perceive and use information.

The tendency to use norms and values of one's own culture or subculture as a basis for judging others is called ethnocentrism. One of the major contributions of anthropology to social science is the recognition of the importance of ethnocentrism and the recognition of cultural relativity, that is, other cultural patterns are regarded as being intrinsically worthy of respect.

A value system is a set of roles, ideals, goals, institutions, or actions that is desirable or admirable in a particular culture. A value system can motivate complex behavioral sequences and produce consistently adaptive acts. It is not advanced technology that is the height of human achievement (that is too new); it is the efficient way in which we transmit values.

Value systems are different from less generalized rule systems in that value systems set goals to work toward or to avoid. They focus energy and effort. Each individual is primed to acquire value systems at the appropriate time in development. Furthermore, a value system can exist with no reinforcement other than mental processes, and sometimes can survive the most extraordinary negative stimulation. An unusual property of some values is that they are adaptive only as goals. However, it can be catastrophic for some of the goals to be realized - converting all the grass into cows, for example.

Protocultures are also characterized by value systems.

[We always have cats at the farm. My wife and I both have allergies, so the cats are outdoor cats. But sometimes we allow a cat inside for a few minutes. They already know the house is a source of food and treats. When a cat has kittens, the kittens learn from the mom that it is desirable to find a way to get into the house. Without the experience inside, they only know that they value getting inside. If one of the kittens manages to dash in the door, they are suddenly disoriented and confused. They only know they should want to get inside, they don't know what to do once they succeed. This is an easy example of a value system in our cat's protoculture.]

Though our technological world is rapidly changing, slow rates of adaptation of our value systems leave our social and economic institutions challenged by pressures of change. This slow rate of adaptation for our value systems appears to be an Achilles heel in a rapidly changing world. Humanity's emotional biology has evolved to be adaptive in the past, but we must live in a nuclear age of electronic communication and vast human populations. Although we have access to the very chemistry of life, our value systems sometimes deny us its medical and social benefits.

Culture is humanity's ecological niche; humans depend upon on culture to solve their environmental problems and to supply their needs. Though continued human population growth reflects our success in overcoming a myriad of obstacles to growth, it is uncertain that we will be successful as a species in dealing with the consequences of that increase.

The Subdiscipline of Physical Anthropology

Integration of four fundamental concepts is necessary to an appreciation of the nature and importance of physical anthropology:

(1) the chemistry of life,

(2) evolution as process,

(3) the interdependence of participants of a global ecosystem, and

(4) the role of culture in human adaptation.

No matter how well one may master a particular topic, the usefulness and importance of this knowledge ultimately depend upon our ability to appreciate how these concepts relate to each other.

Our past and our future are shaped by forces that operate on a scale and time frame outside of human experience. In spite of this, we are beginning to understand our world and the physical universe beyond it through the window of science.

Biological Continuity

A basic tenet of modern science is the idea of biological continuity, the idea that, once established, all life comes from life. Evolutionary theory, as formulated in the 19th century, made this continuity more understandable by proposing natural (in contrast to supernatural) mechanisms for change over time and for descent with modification. As one nineteenth century biologist phrased it, "...the whole evolution of man, in his embryology and in his phylogeny, there are no living forces at work other than those of the rest of organic and inorganic nature" ( Haeckel, 1905; page 879). Modern molecular biology has confirmed the basic homologies in the chemistry of life.

Anthropological Perspective

The anthropological perspective includes certain presumptions about humans. There are many ways to view this universe and all of us use a combination of several approaches in our daily lives. For example, if one follows a recipe without understanding causal relationships between processes, one is practicing magic (in the anthropological meaning of the word) to produce some future event. If the attempt fails, it is because one either deviated from the procedure, used defective ingredients, or was overpowered by the actions of another magician who followed a stronger recipe. All of us do things every day that fall into the category of magic. Further, one could choose to manipulate a future event by an appeal to a deity or to a force (religion). Superstition is a belief in a correlation that is spurious or demonstrably false. On a cold morning, even scientifically minded persons may invoke magic, religion, and superstition as they attempt to start their cars.

Although generalizations may rise and be dismissed in light of subsequent information, perspective of diverse disciplines is different. Perspective affects the goals, methods, and value systems of the participating scientist. Right or wrong, it exerts great influence. The presumptions of holism, biological continuity, and cultural relativity (there is no culture-free standard of judgment...) are some of the features of an anthropological perspective that distinguish it from other sciences.

Anthropology is important as a discipline in which biological and social sciences merge to attend the whole human phenomenon. Human behavior is likely to determine whether the future is bright or tragic. More than a century ago scientists demonstrated that evolutionary processes shaped human biology. In this century we have begun to comprehend the chemistry of life, the mechanics of reproduction, the principles that drive evolution, the complexities of ecology, and the major features of human evolutionary history. Our adventure of discovering what it means to be human is just beginning.

Science as a Way of Understanding

Physical anthropologists use scientific methods in their studies. Science is not a body of knowledge, although knowledge is important to science. Science is a creative activity whereby we try to understand the natural processes that shape our universe. It is conjecture that is verified by observation or experience, and each conjecture is discarded when faced with contrary evidence or a simpler explanation. In its simplest form, science is the practice of thinking critically. A statement is not accurate because some authority claims it is, but rather because it is demonstrably or logically accurate. Thus, science includes an implicit questioning of authority.

Generally, the scientific method is a hierarchy of steps from events to hypotheses that might be organized as follows:

1. A person experiences the real world of events, processes and objects.

2. The events, processes, or objects are named so they can be described and studied. This assigning of names or definitions is an arbitrary process of classification that is the first level of information organization.

3. Observation or experience forms a body of data.

4. Data are interpreted.

5. Relationships are perceived.

6. Conjecture is used to formulate hypotheses about these relationships.

7. Hypotheses are tested on new sets of observations.

8. Particularly useful explanations sometimes merit recognition as theory.

Once a hypothesis or theory is formulated, it is tested by further experiment, producing an alternating cycle between hypothesis and experiment. The majority of scientific work is spent in levels 1 through 5. Models at level 5 or lower are valued because they allow us to predict events. Models or paradigms at level 6 or 7 receive the highest acclaim because they promote understanding, representing organizing principles upon which we pin our insights.

Method refers to the procedures and rules that a scientist uses to shift information up and down this ladder of abstraction. Computations used to accomplish this task are called statistics. The plan of attack is research design. Instruments are the implements of data recording. (For example, a carefully designed questionnaire is an instrument).

All scientific activities initially involve a classification or categorization of observations. A scientist reviews a set of observations and, by induction, produces a generalization or hypothesis. A theory is a model of the processes or events that the scientist thinks occurred. Models are usually based upon a combination of observations and assumptions, but can be devised entirely from speculation. A good model is simple, but produces interesting and surprising predictions. The next step in the scientific method is to test the predictions to see if the theory is useful. If the predictions are validated, then a decision must be made about their significance. Statistical significance is a decision about validity, usually an estimate of the probability that the predictions were fulfilled by chance events. Biological significance is a judgment, based upon common sense, whether a prediction is trivial or important.

A model may also be entirely descriptive and consist of a quantification of events that comprise a phenomenon. For example, a model of traffic flow on a city freeway is the latter type of model. Although descriptive, it can be a productive step in testing and revising more global theories.

Statistics, computations used during collection, analysis and presentation of data, are important tools. There are two types of statistics; 1) descriptive statistics and 2) probability statistics. Probability statistics are used as research tools both to generate hypotheses (Exploratory Data Analysis) and to test hypotheses (Confirmatory Data Analysis).

The use of exploratory statistics (EDA) is rather like detective work: it is a search for evidence and formulation of hypotheses from clues. Therefore it is vital in this process that the investigator have an open mind. Simple descriptive statistics and graphs are elementary techniques for EDA and they represent one of the most important stages in scientific thought, since this is the most probable moment for a scientist to learn something new or unexpected.

In order to avoid circular reasoning, confirmatory statistics, CDA, (hypothesis testing and inferential statistics) must be conducted on a new, different data set than those used in EDA. CDA usually consists of calculating the probability that an observed result is consistent with a proposed hypothesis. If the probability indicates that there is little chance of an accidental agreement, the computation is recognized as statistically significant. The final step in the sequence of CDA is to decide whether a demonstrated difference of effect is important or relevant. This step, called "estimating biological significance," is the final and most important decision a scientist makes in research and thought. There is no traditional test for estimating biological significance. It is based upon intuition, experience, intelligence, and sometimes prejudice. Though scientists may be guided by data, they are ultimately responsible for exercising good judgment.

Not all scientists work at all levels of scientific method. Some specialize in creating new theory and some generate data sets. Both are important, but in anthropology, documenting new observations may be dangerous to life, health and bank account. In terms of income and recognition, most scientific disciplines pay much higher cost/benefit returns (fame and fortune) for creative theory than for generating new data bases. In reality, scientific progress requires achievement at both ends of the spectrum of anthropological method.

Scientific progress is most likely when something new is undertaken. This can be a new thought, exploration of a new type of data, or construction of the ability to accomplish a new goal. A new technology in microelectronics, developed when America decided to put an astronaut on the moon, produced the present computer and electronic communication technology. Space and weight limitations of spacecraft required smaller and lighter equipment. Thus, the present industries of computers and satellite communications is in part a "spin-off" of the space program.

An exciting feature of doing new things is that one usually does not anticipate the consequences. New information stimulates scientists to form new ideas and new theories. A feature of theory stimulated by new information is that it is more likely to be accurate and productive than speculative theory. That is, if one wishes to understand a phenomenon, testing and thought are usually more productive than merely thought alone.

A scientist deals only with observations and hypotheses, never with causal truths. Once we decide we know a truth, we have left the realm of science. Scientific conclusions are always tentative, falsifiable, and open to future review. By definition, "truth" is not tentative or falsifiable.

For example, one might imagine a society that asserts on the basis of authority that 8+1=9. A child might be punished for not knowing that 8+1=9, and might be told that this assertion is infallible. Suppose this child decides to make lemonade. All ingredients and hardware are assembled:

8 cups of cold water

1/4 cup of powdered lemonade mix

1 cup sugar

8 cup container

large stirring spoon

As ingredients are poured into the container, our child worries that this container will be too small for the task. Surprisingly, it is adequate. Clearly if one is making lemonade, 8+1 is less than 9. The processes of recognizing a deviation from the expected and of devising an explanation for the new observation are the core of scientific thinking.

Relationships that are generally, but not universally, valid may be designated rules. Rules allow convenient ways to express useful patterns. Scientific relationships that have been verified to the point that there is great confidence in their accuracy are known as laws. However, there are few laws in science, and even a law is falsifiable. A theory is an explanation that makes sense out of a set of relationships.

Scientific activities are original. It is inherent in science that its activities involve making observations that have not been made before. The exception to this is experimental replication that is necessary for quality control or verification. It is generally not scientific to repeat activities or experiments that contribute no new information or ideas. Thus building a bridge is not scientific, but rather a technical activity, unless something new is learned or attempted.

Likewise it is not scientific for an investigator to allow experiments or observations to be contaminated by bias or commitment to a particular point of view. An investigator is obligated to choose a research design that guards against the possibility of experimenter bias in observations and in testing of ideas. A properly designed experiment will survive an investigator's bias, because it will be carefully structured to shield the data from influence. Replications of the experiment or observation by other investigators can further reduce biases.

Science is thus more than a procedure. It is a way of thinking and behaving that includes critical thinking, questioning, testing, revision, peer review, and eventual public accessibility. The vital elements are questioning and testing.

One of the most successful models for scientific thinking has been reductionism, the representation of the whole as the sum of its constituent parts. By breaking a phenomenon into its component parts and figuring out how they function and interact, a model of the larger system is built. Every component that can be understood this way contributes to our understanding of the whole. Though not all subjects can be approached with reductionism, it has been very useful in biology.

Thousands of people have contributed important elements to science. The following pages of this book present a few individuals and a few ideas that have been selected to sketch a storybook thread of progress. An attempt is made to communicate how central ideas shape an anthropological perspective about human biology and its evolution. The resulting tapestry does little justice to a vast landscape of events and processes. It is only the thinnest thread, with many false connections. At times the tapestry includes praise and criticism, but it does not emphasize that these actors were humans imbedded in their own frail world of culture, family, and colleagues. Some of them ventured fortune, health, and even life itself in the adventure of scientific exploration. Most modern students recognize figures such as Charles Darwin. But, handicapped by the culture of his time, the Reverend John Ray, a seventeenth century cleric, made contributions no less ingenuous or important. Both are part of an almost endless set of contributors. However, for the process to make sense, one must remember that scientists do not comprise science.

Science is an attitude and a process, a way of knowing, not the body of knowledge it produces. Anything that enhances this process encourages scientific advancement and growth. Clearly technologies (writing, printing press, electronic computation, and communication,...) can play a role in speed and growth, but whatever the potentials of technologies, culture and value systems are critical since they shape the possibilities of thought and action.

Realistically, it is not the importance of their activities that usually drives scientists, but rather the beauty and fun of exploration and knowledge. It is exhilarating to observe an event or to perceive a relationship for the first time, and it adds to the joy to know that at that moment you may be the first and only person in history to know. Science is for curious dreamers whose imagination leads them to look in the right places for knowledge. In the words of the physicist Richard Feynman (1989; page 243):

"The same thrill, the same awe and mystery, comes again and again when we look at any question deeply enough. With more knowledge comes a deeper, more wonderful mystery, luring one on to penetrate deeper still. Never concerned that the answer may prove disappointing, with pleasure and confidence we turn over each new stone to find unimagined strangeness leading on to more wonderful questions and mysteries - certainly a grand adventure!"

Summary

Physical anthropologists assume that the physical processes that shape our landscape today and the biological processes that shape our lives are the same forces that operated in the past. We also assume biological continuity, that is, we are descended from ancestors. It should be possible to study both these processes and our ancestors. Humans are cultural beings who learn and problem solve far more that do other animals. Human behavior is organized by systems of values that both motivate and limit us. Culture and values are not unique to humanity, but the human niche is the relatively effective way that we learn and communicate values and solutions to problems.

Physical anthropology merges natural sciences (biology, geology, physics,...), forensic sciences (law, criminology,...), and social sciences (anthropology, linguistics, sociology,..) to study humans. Physical anthropologists use the tools of science to generate a body of knowledge and models to understand humanity, its origins, its evolution, and its niche.

Questions for Review

1. What is culture?

2. Why are physical anthropologists interested in culture?

3. How does science differ from most other ways of knowing (such as magic or religion)?

4. How is science different from a body of knowledge?

5. Why is the idea of biological continuity fundamental to evolutionary thinking?

6. Why is research design important?

7. What role does statistics play in science?