ADVANTAGES OF BIPEDALISM
- when upright, can see over grass in search for food and spot predators
- walking on two legs takes less energy than on all fours
- upright exposes less surface area to direct sun rays .:. assists temperature
regulation
- large surface area exposed to wind and air currents to cool body
- temp regulation mechanisms enable survival in variety of niches
- arms free to:
• make, carry and use tools
• hold young
• gather + prepare food
• development of social communication (hand gestures)
*NB: evolutionary theory DOES NOT state that humans evolved from chimpanzees,
but that we share a common ancestor.
3 MAIN LINES OF EVIDENCE to indicate hominids have common ancestor:
1. fossil evidence
2. genetic evidence
3. cultural evidence
1. FOSSIL EVIDENCE
- large number of hominid fossils found
Palaeontologists looked at the following features:
1. bipedalism
2. brain size
3. teeth (dentition)
4. prognathism
5. palate shape (roof of mouth)
6. cranial (sagittal) and brow ridges
- early hominid fossils rare and have been found in Africa, mostly South Africa
- show combination of ape- and human-like characteristics, we call them transitional
fossils
- fossils belong to a genus called Australopithecus (southern ape-man)
- when upright, can see over grass in search for food and spot predators
- walking on two legs takes less energy than on all fours
- upright exposes less surface area to direct sun rays .:. assists temperature
regulation
- large surface area exposed to wind and air currents to cool body
- temp regulation mechanisms enable survival in variety of niches
- arms free to:
• make, carry and use tools
• hold young
• gather + prepare food
• development of social communication (hand gestures)
*NB: evolutionary theory DOES NOT state that humans evolved from chimpanzees,
but that we share a common ancestor.
3 MAIN LINES OF EVIDENCE to indicate hominids have common ancestor:
1. fossil evidence
2. genetic evidence
3. cultural evidence
1. FOSSIL EVIDENCE
- large number of hominid fossils found
Palaeontologists looked at the following features:
1. bipedalism
2. brain size
3. teeth (dentition)
4. prognathism
5. palate shape (roof of mouth)
6. cranial (sagittal) and brow ridges
- early hominid fossils rare and have been found in Africa, mostly South Africa
- show combination of ape- and human-like characteristics, we call them transitional
fossils
- fossils belong to a genus called Australopithecus (southern ape-man)
