Part 3 The Genus Homo Biocultural Challenges
Part Outline • Chapter 7 Homo habilis and Cultural Origins • Chapter 8 Homo erectus and the Emergence of Hunting and Gathering • Chapter 9 Archaic Homo sapiens and the Middle Paleolithic • Chapter 10 Homo sapiens and the Upper Paleolithic
Chapter 7 Homo habilis and Cultural Origins
Chapter Outline • When, Where, and How Did the Genus Homo Develop? • When Did Reorganization and Expansion of the Human Brain Begin? • Why Is the Relationship Between Biological Change and Cultural Change in Early Homo?
Development of Human Culture • Some populations of early hominines began making stone tools to butcher animals for their meat. • The earliest stone tools and evidence of significant meat eating date to about 2.6 m.y.a.
Reorganization And Expansion Of The Human Brain • Began at least 1.5 million years after the development of bipedal locomotion. • Began in conjunction with scavenging and the making of stone tools. • Marks the appearance of the genus Homo, an evolutionary offshoot of Australopithecus.
Reorganization And Expansion Of The Human Brain • Australopithecus relied on a vegetarian diet while developing a massive chewing apparatus. • Homo ate more meat and became brainier.
Early Representatives of the Genus Homo • Since 1960 a number of fossils have been found in East Africa, and in South Africa, which have been attributed to Homo habilis. • From the neck down, the skeleton of Homohabilis differs little from Australopithecus. • Skull shows a significant increase in brain size and some reorganization of its structure.
Comparison of Partial Foot Skelton • Homo habilis (center) compared with a chimpanzee (left) and modern human (right).
Tool Use • Lower Paleolithic artifacts from Olduvai Gorge, Lake Turkana, and sites in Ethiopia required skill and knowledge for their manufacture. • The oldest Lower Paleolithic tools found at Olduvai are in the Oldowan tool tradition. • Oldowan choppers and flakes made the regular addition of meat to the diet possible.
Brain Structure and Tool Use • Tool making favored the development of a more complex brain: • Requires a vision of the tool to be made. • Ability to recognize the kind of stone that can be worked. • Requires steps to transform the raw material into a useful tool.
Sex, Gender and the Behavior of Early Homo • Males supplied much of the meat, while females gathered other foods. • Females shared a portion of what they gathered in exchange for meat. • Sharing required planning and problem solving.
Tools, Food, and Brain Expansion • Increased consumption of meat, beginning about 2.5 m.y.a. made new demands on coordination and behavior. • Procuring meat depended on the ability to outthink more predators and scavengers. • Eaters of high-protein foods do not have to eat as often as vegetarians, leaving time to explore and experiment with their environment.
Language Origins • There is a growing consensus that all great apes share an ability to develop language skills to the level of a 2- to 3-year-old human. • In the wild apes display language skills through gestures.
Language Origins • Regions of the human brain that control language lie adjacent to regions involved in precise hand control. • Oldowan toolmakers, like modern humans, were overwhelmingly right-handed. • In making tools, they gripped the core in the left hand, striking flakes off with the right.
Language Origins • Handedness is associated with lateralization of brain functions and lateralization is associated with language. • Tool making appears to have been associated with changes in the brain necessary for language development.