Lecture 2-2

1. Lecture 2-2 The Beginnings of Human Culture

2. Lecture Outline • To what group of animals do humans belong? • When and how did humans evolve? • Is the biological concept of race useful for studying physical variation in humans?

3. Anthropology: Four Field Discipline • Anthropology includes: • Research on human cultures and languages worldwide and through time. • Paleoanthropologists analyze ancient fossil humans and their ancestors. • Primatologists study the behaviors of our closest animal relatives and other primates. • Others investigate the genetic basis for variations among human populations.

4. Human Cultural Adaptation • Cultural adaptations allow people to survive in their environment: • Manufacture and utilize tools. • Organize social units to make searching for food more successful. • Preserve and share traditions and knowledge.

5. Human Cultural Adaptation • Computer technology enables us to organize and manipulate information. • Space technology may enable us to propagate our species in extraterrestrial environments. • Biomedical technology may enable us to control genetic inheritance and the future of our biological evolution.

6. Humans and Other Primates • The human species is one kind of primate, a subgroup of mammals that includes lemurs, monkeys, and apes. • Humans are most closely related to apes: • chimpanzees, gorillas, orangutans, and gibbons

7. Anatomical Adaptation • Preadaptation • Characteristics adaptive to one way of life that also are suitable for a different way of life. • Ancestral primates • Preadapted to arboreal life favored by natural selection. • Over time • Arboreal life involves changes in various anatomical features.

8. Primate Dentition • Diet available to arboreal primates requires unspecialized teeth. • Over time, there is a trend toward economy, with fewer smaller teeth doing more work: • Number of incisors decrease. • Number of cusps on molars increases.

9. Sense Organs • Decrease dependency upon sense of smell. • Increase dependency upon sight: • Stereoscopic color vision • Corresponding increase in brain size in the visual area • More acute sense of touch.

10. The Primate Brain • An increase in brain size, particularly in the areas supporting conscious thought occurred in the course of primate evolution. • In monkeys, apes, and humans the cerebral hemispheres cover the cerebellum, the part of the brain that coordinates muscles and maintains balance. • Rather than relying on reflexes controlled by the cerebellum, primates constantly react to a variety of features in the environment.

11. The Primate Brain • Messages from hands and feet, eyes and ears, and balance, movement, heat, touch, and pain sensors are simultaneously relayed to the cerebral cortex. • The cortex had to develop in order to receive, analyze, and coordinate these impressions and transmit a response back to the motor nerves. • The enlarged, responsive, cerebral cortex provides the biological basis for flexible behavior patterns found in all primates, including humans.

12. The Primate Skeleton • Opening of the skull for the spinal cord shifts forward toward the skull’s base accommodating upright posture. • Snout or muzzle portion of the skull reduced • Arms at side rather than the front part of the body • Retention of the primate prehensile hand with opposable thumb

13. Primate Skeleton Bison skeleton (left) and Gorilla skeleton (right)

14. Adaptation Through Behavior • Arboreal life involved changes in behavior as well as in anatomical features. • Learned social behavior plays an important role: • Social behavior rarely observable in fossil record • Examination of contemporary primate behavior may lead to clues to early primate behavior and the emergence of human cultural behavior

15. Chimpanzee Behavior • Communities with open subgroups • Males generally move • Male dominance with mother important in determining rank • Maintain strong mother-child bond • Grooming is a common pastime • Promiscuous sex when female is fertile • Settle disputes by aggressive behavior • Dependence upon cultural behavior • Make and use tools • Males hunt in groups and share kill

16. Reconciliation and Its Cultural Modification in Primates • There is evidence for reconciliation in more than 25 different primate species. • Reconciliation is common mechanism found whenever relationships need to be maintained despite occasional conflict. • Chimpanzees are the only animals to use mediators in conflict resolution. • Reconciliation is a learned social skill subject to what primatologists now increasingly call “culture”.

17. Human Ancestors • Chimpanzees and gorillas • Closest living relatives to humans • Humans, bonobos and chimpanzees 98.5% genetically identical • Separation from a common stock • Genetics suggest divergence at least 5.5 million years ago • Fossil evidence shows separation at least 4.4 mya

18. Human Ancestors • Ancestors of humans • Most likely apelike animals • Living in Africa • Forced by climactic changes to leave trees

19. Monkeys, Apes, and Humans • Molecular evidence indicates the split between the human and African ape lines took place between 8 and 5 million years ago.

20. The First Hominines: Australopithecus • Earliest well-known hominine, who lived between 1 and 4.2, if not 5.6 m.y.a. and which includes several species. • Found in eastern Africa and westward into Chad • Fully bipedal • Brain appears apelike • Teeth more like modern humans than apes • Males about twice the size of females • Likely depended upon animal flesh in diet

21. Homo habilis • Earliest species of the genus Homo • Increased consumption of meat • Living primarily on the savannah • Scavenging from carcasses • Dentition not suited for meat eating, so they probably needed tools to butcher carcasses. • Increased brain complexity and size

22. Homo habilis • Culture • Using wits to compete with large animals • Food sharing and preparation • Butchering sites where carcasses are brought

23. Homo habilis • Invention of tools about 2.5 million years ago • Oldowan tools • Striking flakes from core • Paleolithic • The Old Stone Age, characterized by chipped stone tools.

24. Homo erectus • Species directly ancestral to modern humans • Had a body size and proportions similar to modern humans, though with heavier musculature. • Average brain size fell within the higher range of H. habilis and the lower range of modern human brain size. • Dentition was fully human, though relatively large by modern standards.

25. Homo erectus • Culture • Fire and cooking circa 700,000 years ago • Toolkit diversity • New tool making techniques • Selectivity of raw material • Evidence of organized hunting as the means for procuring meat, animal hides, horn and bone.

26. Homo sapiens • First appear about 300,000 years ago • Archaic Homo sapiens • Neanderthal • Europe and Asia • Large brained • Massive face • Other groups found in Java, Zambia, China • Modern Homo sapiens • Less massive face • Less bony architecture

27. Anatomically Modern Peoples and the Upper Paleolithic • Upper Paleolithic peoples • First people of modern appearance, who lived in the last part of the Old Stone Age. • Culture emerges as a more potent force than biology • Tools surpass the physical equipment of predators • Bow and arrow

28. Tool Making: Upper Paleolithic • A technique used to manufacture blades: The stone was broken to create a striking platform, then vertical blades were flaked off to form sharp-edged tools.

29. Anatomically Modern Peoples and the Upper Paleolithic • Art • Decoration • Sculpture • Pendants • Cave painting • Ritual • Trance • Burial

30. Race and Human Evolution • Anthropologists agree no subspecies exist within currently surviving Homo sapiens. • As far as contemporary humanity is concerned, race is not a valid biological category. • Anthropologists work to expose the concept of race as scientifically inapplicable to humans.

31. Race as a Cultural Construct • Although biological variation exists in the human species, biological races or distinct subspecies do not. • Variation such as differences in skin color is the result of genetically adaptive processes to different natural environments. • The majority of human variation exists within populations rather than among populations due to • independent inheritance of individual traits • genetic openness of human populations