Hominin footprints preserved at Laetoli, Tanzania, are about 3.6 million years old. These individuals were between 3 and 4 feet tall when standing upright. For a close-up view of one of the footprints and further information, go to the human origins section of the website of the Smithsonian Institution’s National Museum of Natural History, www.mnh.si.edu/anthro/ humanorigins/ha/laetoli.htm. THE EVOLUTION OF HUMANITY AND CULTURE 2 the BIG questions v What do living nonhuman primates tell us about OUTLINE human culture? Nonhuman Primates and the Roots of Human Culture v Hominin Evolution to Modern What role did culture play Humans during hominin evolution? Critical Thinking: What Is Really in the Toolbox? v How has modern human Eye on the Environment: Clothing as a Thermal culture changed in the past Adaptation to Cold and Wind 12,000 years? The Neolithic Revolution and the Emergence of Cities and States Lessons Applied: Archaeology Findings Increase Food Production in Bolivia 33 Substantial scientific evidence indicates that modern hu- closest to humans and describes how they provide insights into mans have evolved from a shared lineage with primate ances- what the lives of the earliest human ancestors might have been tors between 4 and 8 million years ago. The mid-nineteenth like. It then turns to a description of the main stages in evolu- century was a turning point in European thinking about tion to modern humans. The last section covers the develop- human origins as scientific thinking challenged the biblical ment of settled life, agriculture, and cities and states. narrative of human origins. Two British thinkers, Charles Darwin and Alfred Russel Wallace, independently discovered vvv the principle of natural selection, the process by which or- ganisms better adapted to the environment reproduce more Nonhuman Primates and the effectively compared to less well-adapted forms. This princi- Roots of Human Culture ple, in turn, supported the acceptance of the concept of evolution, or inherited and cumulative change in the charac- According to abundant evidence from genetics, anatomy, teristics of a species, population, or culture. This scientific physiology, and behavior, humans are primates. This section view conflicts with some religious perspectives, including describes primate characteristics in general and then situates Christian creationism, based on a literal understanding of bib- humans within the group of primate with whom we are most lical writings, that all animal species, including humans, date closely related in order to provide some comparisons. from the Day of Creation and have always existed in the physical form that they do now. The scientific view of human PRIMATE CHARACTERISTICS origins, however, does not conflict with all religious perspec- The primates are an order of mammals that includes modern tives, including nonliteralist Christians and Buddhists. humans. Primates vary in size from several ounces to over Fossils (the preserved remains of a plant or animal of 400 pounds. Some inhabit limited areas, and others range the past), artifacts (portable objects made or modified by more widely. In defining primate characteristics, morphology, humans), and new genetic analyses provide strong evidence or physical form, is a basic consideration because it is related that modern humans existed before the Christian Day of to behavior. Compared to the faces of other mammals such as Creation, estimated to be 4004 BCE. The evidence also shows dogs or cows, primate faces tend to be flat with reduced that human anatomy evolved over time from more ape-like to snouts. Relatedly, primates differ from other mammals in more human-like, and human cultural capabilities have terms of being highly reliant on vision for dealing with their changed dramatically. Many anthropologists, like other scien- environment and social interactions. Primates have five digits tists, find ways to reconcile the scientific evidence with their on their hands and feet, opposable thumbs, and they can grasp personal religious beliefs. with both their hands and feet. Primate brains are large in re- This chapter accepts the scientific perspective on human lation to body size. Because of their large brain size, primates evolution. It therefore begins with a discussion of the primates take longer to mature than other mammals do. This extended Members of a group of Hanuman langurs in India involved in social behavior. Most primates are highly social and interact with their group-mates in complex ways. 34 PART I INTRODUCTION TO CULTURAL ANTHROPOLOGY MAP 2.1 Where Nonhuman Primates Live Today. The habitats of nonhuman pri- mates are greatly reduced from what they were in prehistory, and they are increasingly threatened by human encroachment and environmental change. 01,500 3,000 Miles 01,500 3,000 Kilometers developmental period, combined with the fact that most pri- use to gouge the outer layer of trees to start the flow of mate species are highly social, provides a context for the social gums and saps. Many have large intestines to help them molding of primate behavior. digest these food sources. In terms of environmental adaptations, most nonhuman • Omnivores are generalists: many kinds of foods make up primate species live in low-altitude areas of the tropics or sub- their diet. Therefore, they lack specialized dental or gut tropics (see Map 2.1). A few live in high altitudes in Africa, morphology. Humans are omnivores. Nepal, and Japan. Most primate species are arboreal (tree- dwelling), quadrupedal (moving on all fours), and diurnal Most primates live in a social group, or collection of ani- (active during the day), and most, like humans, have a high mals that interact regularly. Group life has advantages in terms degree of sociality, or a preference for living in groups and of information sharing about food sources and protection interacting regularly with members of the same species. against threats from other groups. The details of group organi- All nonhuman primates in the wild provide for their zation vary.The most common social group among nonhuman food needs by foraging, or obtaining food available in nature primates, by far, is the multi-male/multi-female (MM/MF) through gathering, hunting, or scavenging. Species vary, how- group. This type of group contains adults of both sexes and the ever, in terms of the kinds of foods they prefer (Strier 2007). females’ offspring. Females make up the core of the group and Five major dietary patterns of primates are based on their often have strong alliances with each other. Male membership primary food sources: in these groups is less stable. A rare subvariety is called a fission-fusion group, a large group of 50 or more individuals that • Frugivores eat mainly fruit. They have large front teeth, regularly breaks up into much smaller subgroups for foraging. or incisors, to allow them to puncture the flesh of large Although rare among nonhuman primate species overall, fruits and transfer pieces into their mouths, like when the fission-fusion pattern is important because it is found in you bite into an apple. Digestion of fruits occurs in the chimpanzees and bonobos, the nonhuman primates most like small intestine, so frugivores have a long small intestine. humans. Thus it is possible that the early human ancestors may • Folivores eat primarily leaves. Leaves are difficult to di- have had a fission-fusion form of social organization. gest because of the chemicals, such as cellulose, in their walls. Folivores’ chewing teeth are designed to help them natural selection process by which organisms better break leaves into small pieces, and bacteria in their diges- adapted to the environment reproduce more effectively tive systems break down the cell walls of leaves. Some compared with less well-adapted forms. folivores have an expanded large intestine (Milton 1984). evolution inherited and cumulative change in the • Insectivores eat mainly insects. They have high, sharp characteristics of a species, population, or culture. cusps on their molar teeth to puncture and break up the fossil preserved remains of a plant or animal of the past. insects’ hard covering. The contents of insects are quite artifact portable object made or modified by humans. easy to digest, so insectivores have short and simple primates order of mammals that includes modern humans. guts. Insects are difficult to catch, so the limited food sociality preference for living in groups and interacting sources mean that insectivores are small-bodied. regularly with members of the same species. • Gummivores have a diet that relies on the gums and saps foraging obtaining food available in nature through of trees. Some have protruding lower incisors that they gathering, hunting, or scavenging. CHAPTER 2 THE EVOLUTION OF HUMANITY AND CULTURE 35 the lives and behavior of early human ancestors might have Orangutans Gorillas Chimpanzees Modern been like. and Bonobos Humans Apes differ from other primates in the absence of a tail, larger brains relative to body size, and the tendency to travel by brachiation. All apes, including humans, are capable of 8 million years ago brachiation, a form of arboreal travel, using the forelimbs to swing from branch to branch, related to changes in the shoul- der anatomy and distinct to apes (see Figure 2.2). Apes are 12 million years ago typically frugivores but they eat a variety of other foods, in- cluding insects such as termites. Mountain gorillas eat mainly 15 million years ago leaves and stalks. Orangutans are the only Asian great ape. They live on the islands of Borneo and Sumatra (see Map 1.1, p. 10). Sexual dimorphism in body size (difference in size between FIGURE 2.1 The Great Apes, Including Modern Humans. males and females) is marked, with the weight of an adult male (175–200 pounds) roughly double that of an adult Complex communication and signaling systems are an- female (73–99 pounds).