Investigating the Nature of Humankind Chapter One Investigating the Nature of Humankind

The World of Physical Anthropology Physical anthropology is the subfield of anthropology that studies human biological evolution. Anthropologists who specialize in this subfield study topics such as genetics, growth and development, evolution, primatology, the fossil record, and modern human variation. Other subfields within the discipline of anthropology include cultural anthropology, archaeology, anthropological linguistics, and applied anthropology.

The Nature of Science The steps of a scientific investigation include empirical observation, identifying variables, proposing a hypothesis, testing hypotheses, and developing generalizations. A theory is a statement based upon highly confirmed hypotheses that generalizes about conditions that are not yet tested. Science is not able to answer all questions. Some questions cannot be subjected to scientific inquiry and therefore are not in the domain of empirical research.

Views on the Essence of Humans, Nature and Time Older ideas established about the nature of the universe had to be challenged before new concepts could arise. Early views included the idea of anthropocentricity, defined as the belief that earth is the center of the universe, and that humans were created to rule over the earth. People of that era also believed that humans and animals were the product of spontaneous generation, and immutable upon creation.

Questioning the Old Ideas In the sixteenth century, Nicolas Copernicus showed that the earth was not the center of the universe, or even the center of this solar system. Carolus Linnaeus created a classification of plants and animals, an important step towards understanding the relationship of one plant or animal to the next. Increased exploration of the world and technological advances in the 18th and 19th century helped lead to the idea that nature could be dynamic.

Early Evolutionary Ideas Many elements of evolutionary thought had been suggested earlier by such theorists as Buffon. Lamarck proposed an early theory of evolution, which suggested the inheritance of acquired characteristics as the mechanism for change. Another important step was establishing the age of the earth. This was accomplished by Charles Lyell and his theory of uniformitarianism.

Darwin’s Voyage of Discovery It was Charles Darwin who proposed a compelling theory for the mechanisms of organic evolution, synthesizing the available evidence. Many of Darwin’s ideas stemmed from his observations as the naturalist on the HMS Beagle. Darwin was on the Beagle between 1831 and 1836 and visited such places as the Galápagos Islands.

Darwinian Natural Selection Based on work by Malthus, Darwin noted that populations grow more rapidly than resources do. More individuals are born than live to reproduce. Individuals vary from one another, and those individuals with traits that are better adapted to their environment are more likely to survive and reproduce. If these individuals pass the favorable trait down to their offspring, the trait will spread throughout the population over time.

Anti-Evolution Movements Darwin’s concept of natural selection has survived over 145 years of biological study, becoming a foundation of modern biological science. There are people who oppose Darwin’s theory, for reasons beyond the realm of science. They believe that evolution should be discarded in favor of a creationist interpretation. That latest battleground is the idea of “intelligent design.” This is essentially a religious, not a scientific, explanation.

The Synthetic Theory The basic concepts of Darwin’s theory of evolution remain the cornerstone of modern evolutionary theory, and have been further built upon. Darwin and others of his time were not aware of the mechanisms of inheritance. The addition of genetic knowledge to Darwin’s ideas has greatly increased our understanding. As this understanding is based on a synthesis of information from diverse fields, it is sometimes called the synthetic theory of evolution.