Biological factors
1. Factors related to Man
- Nervous system- development of brain, PNS, CNS, Encephalization
- Skeleton system – erect posture, opposable thumb, Ulnar opposition, Bipedalism
- Integumentary system – homeostasis and homeothermy
- Digestive system – omnivore diet
- Reproductive system – large gestation period Sexual dimorphism
2. Factors related to Environment
- Elaborate parental care
- End of ice age, inter glacial period
Cultural factors
- Discovery of fire
- Agriculture
- Instruments, implements
- Social organization
- Political organisation
- Language
- Wheel
- Economic organisation
