some information about Australopithecus species with a short prologue about Ardipithecus species

1. Directed By:
Hamed Almasi

3. Ardipithecus
-Lived in 5.8 - 4.4 Mya
(the end of the Miocene & beginning of the Pliocene epoch)
-Probably ancestral to Australopithecus Afarensis
-Brain volume was about the size of a modern chimpanzee
-Tim White of Berkeley, the anatomist says:
"Ramidus is the first species this side of our common ancestor with chimpanzees."

5. CHAPTER 1:
AUSTRALOPITHECINES MORPHOLOGY
-Lived in East and South Africa between 4.4 and 1.4 Mya
(The Pliocene & the beginning of Pleistocene epoch)
-Trend toward larger brain size
-Brain enlargement probably arose in response to changes in foods habitat
-Brain volumes ranges from 435 to 650 cc
-Between 1.2 to 1.4 m tall
-Sexual dimorphism in earlier creature
-The normal lifespan was about 25-30 years
-Ate meat & plants(friuts.nuts,roots,eggs,lizard,fishs,carrions,...)
-Lived with: saber-thoothed tiger,lion,hyraxes,rats,baboons,pigs,monkeys,hippos,...

6. 1. Change in diet
- less “tree” food
- more open ground foraging, e.g. seeds, grasses, roots
2. Change in dentition
- smaller canine teeth
- male canines became as small as those of females

7. CHAPTER 2:
AUSTRALOPITHECINES SPECIES
Gracile Species Location
• Australopithecus Anamensis Kenya
• Australopithecus Afarensis Ethiopia & Tanzania
• Australopithecus Africanus South Africa
• Australopithecus Garhi Ethiopia
Robust Species Location
• Australopithecus Robustus South Africa
• Australopithecus Aethiopicus Kenya
• Australopithecus Boisei Kenya
Australopithecus BahrelGhazali East Africa
Australopithecus Sediba Chad

8. Gracile Species:
3.9 to 2 Mya in East Africa
3.5 to 2.3 Mya in South Africa
Erect bipeds, about 1-1.5 m. in stature
Apelike skull morphology
Teeth for chewing food in a hominin fashion

9.  Earlier fossils show dental features similar to some late
Miocene apes; later South African fossils do not
 Sexually dimorphic, in body size and canine tooth size

10.  Foramen magnum is forward and downward-
looking, as in genus Homo
 Brain is about a third of a modern human brain
in size, and three times larger than Miocene apes
 Endocasts suggest that the human cerebral
reorganization has not yet occurred
 Blood drainage system for the brain is
significantly different from genus Homo

11. South Africa
 1.8 to 1 million years ago
 Thick bones for their size, with
prominent muscle markings
 Sagittal crest, for huge temporal
muscles (more evident in males) – an
example of convergent evolution in
gorillas and hominins
In South Africa the robusts were either an offshoot of the East
African lineage, or convergent evolution from a South African
ancestor

12. East Africa
 2.5 to 1.3 million years ago
 More massive skull and larger body size than
South African relatives
 Enormous molars, premolars, mandible and
palate
East African robust forms likely evolved from earlier
gracile forms in east Africa

13. Chapter 3:
Australopithecus Anamensis

15. Chapter 4:
Australopithecus Afarensis

16. To Homo ?
“robust
Australopithecines”
Australopithecus garhi e.g. Paranthropus
(Australopithecus)
boisei
? ?
?
Australopithecus afarensis Australopithecus africanus
Australopithecus anamensis
Ardipithecus ramidus

17. Australopithecus Afarensis Skull

19. Australopithecus Afarensis Body
Ground or tree-dweller?
• Slightly curved hand & foot bones
• Relatively long and powerful arms
• Bowl-shaped pelvis
• Knock-kneed (knee joint angled
inward)
• Heel bone heavily built (like ours)

22. Anatomical Adaptations for
Habitual Upright Bipedalism
A comparison of the
chimp, human, and
A. afarensis femurs
demonstrates a
rounder femoral
head and longer
femoral neck length
in hominids.

23. Lucy: first A.Afarensis found

24. Australopithecus Afarensis Footprints
• Laetoli, Tanzania: home to a footprint trail 3.5 m.y. old
• Probably a trackway of A. afarensis

25. An A.Afarensis 3 yrs old baby girl
• Ethiopia (Hadar)
• Lived 3.3 m.y.ago
• Ape-like scapula
• Human-like knees
• Finger bones partially curved
• Heel bone well-developed
• Endocast shows delayed brain
growth (like us)
• Chimp-like hyoid bone

26. Chapter 5:
Australopithecus Africanus

27. • 3.5 - 2.0 m.y.a.
• Mainly S. Africa
• Mixture of habitats
• Fruit, salads, insects, small easily captured prey
• Sexual dimorphism
• (male:1.3m&41kg - female:1.1m & 30 kg)
• Brain size: 1/3rd ours
• Relationship to other hominids? Unknown
This species slightly different from A. afarensis: slightly taller, less facial
prognathism, slightly larger brain. Also lived in drier habitats (especially dry
scrublands and perhaps open grasslands), and thus may have exploited
different resources.

31. Chapter 6:
Australopithecus Garhi

32. • 3.0 - 2.0 M.y.a.
• Eastern Africa (the site of Bouri, Middle Awash, Ethiopia)
• Fruit, salads, insects, small easily captured prey
• Brain size: About 450 cc
• The dental arcade is U-shaped
• link between the genus of Australopithecus and Homo

35. Chapter 7:
Australopithecus Robustus

36. • 1.9 - 1.2 m.y.a.
• Southern Africa
• Sexual dimorphism
• (male:1.2m&54kg - female:under 1m & 40 kg)
• Large sagittal crests, jaws, jaw muscles, and
post-canine teeth
• Brain size: 410 - 530cc
• Teeth were larger and thicker than any Gracile
Australopithecus

38. Chapter 8:
Australopithecus Aethiopicus

39. • 2.7 – 2.5 M.y.a.
• Eastern Africa
• As tall as A. afarensis
• (male:1.5m - female: 1.05m)
• Large sagittal crest and zygomatic arch
• Brain size: About 410 cc
• Ate very tough, grainy foods

41. Chapter 9:
Australopithecus Boisei
boisei

42. NutCracker Man!
• 2.3 - 1.2 m.y.a.
• Ethiopia, Tanzania, and Kenya in East Africa.
• Face is more vertically set, more orthognathic
• Low forehead
• Foramen magnum located more anteriorly
• Sexual dimorphism
• (male:1.3m&68kg - female:under 1.05m & 45 kg)
• Low vaulted brain case
• Brain size: 500- 550cc
• The biggest, flattest cheek teeth and the thickest enamel of any
known hominin

44. Chapter 10:
Australopithecus Bahrelghazali
• 3.5 – 3 M.y.a.
• Central Chad in Africa
• May be closely related to A.afarensis
• Jaw and teeth features to other australopithecines
• Probably similar in size to modern chimpanzees
• Large incisiform canines and molars
• Premolars with 3 roots
• Brain size: 400- 550cc

45. Chapter 11:
Australopithecus Sediba

46. • 1.95 – 1.78 M.y.a.
• Southern Africa (South Africa)
• brain of the juvenile was human-like in shape,but
still much smaller than in Homo specie
• generally thinner and lighter jaw, smaller teeth
• the legs are quite long
• pelvis appears to be more adapted for walking
• Brain size: 430 cc

50. HUMAN EVOLUTION!
Finish