1. The Incredible Journey
Human Evolution
The Incredible Journey

2. Recap – Natural Selection
There is variation between individuals in a population
Parents pass on their traits to their offspring
The organisms with features that best suit their environment have the best chance of survival and reproduction
Those organisms that are able to survive and reproduce pass on their characteristics to their offspring
Over time the population will become better suited to its environment
Let’s give it a try...

3. Natural Selection Human Adaptations that have been selected for;
Bipedalism (position of the ‘foramen magnum’)
Reduction in size of molar teeth
Reduction in jaw size
Increased cranial capacity
Cranial ridge

4. Comparison of skulls CHIMPANZEE GORILLA HUMAN SKULL
What features can you identify?
What makes the skulls different from one another?

5. Comparison of skulls
Top of the skull (cranium) is smooth There is no anterior-posterior crest to hold huge jaw muscles 
No protruding brow
No protruding jaw or teeth (ie the teeth are vertical)
No protruding nose bone
Teeth are arranged in a parabolic shape rather than a narrow u shape
Small canines and small incisors 
Foramen magnum (hole for the spine) is positioned directly underneath the skull not in the back of the skull

6. Australopithecus aferensis
Location: Eastern Africa
Cranial capacity : cc
Fossils discovered so far in Tanzania, Kenya and Ethiopia
Timeframe: 4.7 – 2.1 million years
Fully bipedal (first!), but arms longer than legs
Possibly made tools out of bone teeth and horn (Osteodontokeratic)

7. Australopithecus africanus
Location: Southern & Eastern Africa
Cranial capacity: cc
Timeframe: 3-2 million years
Slightly greater body size
Smaller canine teeth than A. aferensis
Teeth structured in a more parabolic (‘V’) shape

8. Australopithecus boisei (Oldoway)
Location: Eastern Africa
Cranial capacity: cc
Timeframe: million years
Largest teeth found in any hominid group
Huge jaw, small incisors & canines, large molars & premolars, parabolic dental structure and sagittal crest present – (hard low quality food)
Face is more vertically set

9. Homo rudolphonsis Earliest species of Homo (or maybe Homo habilis?)
Cranial capacity: 775cc
Contention as to whether the fossils are Australopithicus or Homo
Lack of crests
Smoothly rounded occipital bone compared to Homo erectus

10. Homo habilis “handy man”
Location: Eastern Africa
Cranial capacity: 800 cc
million years
Short molars, small canines, parabolic dental arcade
Full biped, increased leg length, decreased arm length, shorter in stature
Fossils accompanied by primitive stone tools

11. Homo erectus Location: Africa, Asia, Europe
Cranial capacity: cc
Useing Acheulian tools: hand axe culture, large game hunting, suggestion of communication, first to use fire
Some scientists have split H. erectus into three separate species, based on the geographic region in which specimens have been found: H. ergaster (Africa), H. erectus (Asia), and H. heidelbergensis (Europe).

12. Homo sapien Location: Africa, Asian, Europe, Australia, North America
A high, rounded cranium
Cranial capacity: cc
Art & Symbolism, first to produce fire and use language
A steep forehead
A tall and narrow nasal opening
A parabolic palate