1. Beginning of Human Culture
Chapter 3
Cultural Anthropology

2. Human culture came into existence 2.5 million years ago
This is when humans began to rely more on learned behaviour for survival

3. Humans and the other Primates
Humans belong to the primate order
Also includes lemurs, lorises, tarsiers, monkeys and apes

4. The first primates originated at a time when a new, mild climate favours the spread of dense tropical and subtropical forests over much of the earth
Forestation set the development of evolution from the ground to tree living

5. Evolution through adaptation
Adaptation refers to both a process organisms undergo to achieve a beneficial adjustment to an environment and the results of that process
Natural selection favours the survival of well-adapted individuals and the propagation of their genes
Well-adapted individuals produce greater percentage of offspring for next generation
Less suited individuals may survive but often do not reproduce because they may be incapable of attracting a mate, be sterile or produce offspring that die

6. What types of adaptations do you think would enhance survival in the trees?

7. Ancestral primates possessed characteristics that allowed them to survive in the forest
Small size allowed them to use branches of trees that larger and heavier competitors could not and gave them access to an abundance supply of new food
These primates could gather this food without having to wait for them to fall to the ground
This adaptation to the trees required physical adjustments

8. Anatomical adaptation
There exists characteristics common to all primates
Primate dentition
Diets of shoots, leaves, insects and soft fruit didn’t require specialized teeth
Primate ancestors had 44 teeth
Three incisors used for gripping and cutting, 1 canine used for tearing and shredding and four molars and three premolars used for grinding and chewing
Evolutionary trend for primate teeth is toward smaller and fewer teeth
Canines grew longer and first and second premolars became smaller and eventually disappeared and third and fourth premolars became bicuspids

9. Sense organs
For mammals on the ground the sense of smell is extremely important in that it helps them operate at night and sense what is out of sight
This allows ground animals to smell out food and predators
In the trees, primates are away from predators and good vision is more important than smell in guiding through branches
Thus the sense of smell declined and the sense of vision developed

10. Stereoscopic colour vision in primates creates the ability to see the world in three dimension of height, width and depth
This is accomplished with two eyes set next to each other on the same plane so the visual field of two eyes overlap
This has led to increased brain size in the visual areas in primates and a greater complexity at nerve connections

11. A more accurate sense of touch also characterized arboreal primates
A good feeling and mechanism for grasping allowed them from falling from the branches as they sped through the trees
Early mammals from which primates evolved had little hairs that gave them tactile sensitivity with were replaced by sensitive pads backed by nails in the tips of the fingers and toes

12. The cerebral hemispheres have grown dramatically
The primate brain
The most outstanding characteristic of primate evolution is the increased brain size
The cerebral hemispheres have grown dramatically
In monkeys, apes and humans they completely cover the cerebellum which is the part of the brain that coordinates the muscles and maintains body equilibrium
This is likely the result of their arboreal existence
Living in the trees means an animal is constantly reacting to its environment in complex ways
Signals from all parts of the body about various environmental factors have to simultaneously be relayed to the cortex, processed and then an appropriate response has to be sent down the motor nerves to the appropriate receptors
This enlarged cortex not only allowed for survival in the trees but also paved the way for the capacity for heightened thought

13. The primate skeleton
The trend in primates is for the foramen magnum, the hole at the base of the skull that the spinal cord attaches to, to move toward the base of skull
In quadrupeds this hole in higher in the skull
This shift allows for an animal to move in a more upright position

14. In most primates the snout or muzzle portion of the skull is reduced as the sense of smell has become less important
This smaller snout offers less interference with stereoscopic vision and enables the eyes to place in a more frontal position

15. A developed orbital bone provides more protection for the eyes
The clavicle or collarbone moves the arms to the side and allows for more movement with allowed primates to swing through the trees
At the end of the hands and feet there exists five extremely flexible digits
At the end of the digits are sensitive pads backed by nails which acts as an effective grasping mechanism
The opposable thumb and great toe allow for greater manipulation of food, branches and other objects

16. Adaptation through Behaviour
Jane Goodall’s work in studying chimps in Tanzania has provided an insight into the behaviour of our ancient ancestors

17. Like all primates, chimps are social creatures
Chimpanzee behaviour
Like all primates, chimps are social creatures
A community of chimps can be up to 50 or more individuals
These rarely gather at once and are usually found in subgroups consisting of adult males together, females with their young, or males and females with their young
Subgroups may join forces to forage together but eventually break up again into subgroups
When this happens members are often exchanged and new subgroups are composed that are different than the ones that initially came together

18. Dominance hierarchies can exist, despite the fact that most relationships between individuals in the community are stable
Generally males outrank females, although high ranking females may outrank low ranking males
Physical size and strength determine an animal’s rank but what really counts is mother’s rank and how that rank creates alliances

19. Grooming is a common chimp pastime
Besides being hygienic, it’s a gesture of friendliness, submission, appeasement and closeness
This closeness through embrace and touching is an expression of social stability

20. The sexes intermingle continually and like humans there is no fixed mating season
Sexual activity occurs only during the month that the female is fertile and can be initiated by either the male or the female
Once impregnated a females are not sexually receptive until their offspring are weaned, at around four
Chimps are relatively promiscuous and so it is not guaranteed that a dominant male will impregnate a particular female
Nonetheless a dominate male may try to monopolize a female
But the female may exercise choice in that cooperation from the female is necessary and she may make herself scarce by going to a neighbouring group
Alpha males have been known to monopolize many females at the same time

21. In primates, females and their offspring constitute the core of the social system
Among chimps the mother-infant bond is especially strong in the first five years and a close association continues after this
Commonly sons and daughters remain with their mothers for life, even if the mother leaves the group

22. Chimps appear to rely much on learned cultural behaviour
This behaviour can be different from one chimp group to another
E.g.: tool use, social interaction

23. Human Ancestors
Studies in genetics, biochemistry and anatomy confirm that chimpanzees and gorillas are our closest living relatives
Both are more closely related to us than orangutans
98% identical at genetic level
Estimated that we split up 5.5 to 8 million years ago on evolutionary tree

24. Moving from one stand of trees to another
Ape like human ancestors were forced from the trees onto the ground as a result of climate changes that shifted the environment from a forest to grass
Moving from one stand of trees to another
Food was also getting scarce in the trees
They likely walked on their hind legs as they didn’t have large upper bodies or long arms and thus their hands were free to gather food and transport it
An erect posture also aided them in transporting their offspring more effectively and reduced the amount of body area exposed to the sun which helped avoid overheating

25. Activity
In groups you will create mini poster presentations based on the following pages of your textbook.
Groups
First Hominines pg
Homo habilis pg
Homo erectus pg
Homo sapiens pg