Australopithecines Flashcards
What two genera can australopiths be broken down into?
- Australopithecus
- Paranthropus
What is an austrolapith?
- Found from 1-4 million years ago
- Found in east Africa (older sites)
- Found in south Africa (found here first)
- Australopithecus afarensis is the most well known species, most of what we know is from this species
What species is a weird mixture of autralopithecus and paranthropus?
Kenyanthropus platyops which existed from 3.2 - 3.5 million years ago
What is Australopithecus anamensis?
- The oldest australopith
- Found in Kenya/Ethiopia 3.8 - 4.2 million years ago
- Primitive box shaped jaw, bigger canines that later australopithecines, upper limb features for arboreality
- Derived smaller canines, thick enamel, large molars, knee and ankle for bipedalism
- Probably lived in mixed habitats (grassland and woodland)
What is Australopithecus afarensis?
- Found in east Africa 2.9 to 3.7 million years ago
- Lived in mixed habitats (forests, savannah, woodlands)
- “Lucy” found in Hadar, Ethiopia
- Dikika child
Why is Australopithecus afarensis so interesting?
- Largely representative of all australopiths
- Mixture of primitive and derived traits that are intermediate
- Face prognathic
- Medium canines
- curved tooth rows
- large molars, pre-molars with thick enamel
- Large neck and chewing muscles
- Ape like brain
- Moderate canine and sexual dimorphism
What are changed in Australopithecus afarensis due to locomotion?
- Pelvis: illium flared and rotated to allow hip abductors to keep body over midline, sacrum ilium joint enlarged for more weight bearing
- Femur and knee: femur angled towards midline, minimizes side to side motion when walking, puts knee (support structure) under trunk
- Foot: enlarged heel, arch to stiffen foot, big toe in line with other toes
What are the arboreal retentions of Australopithecus afarensis?
- Relatively long arms
- Oriented mobile shoulder joints
- Slender, curved fingers and toes
What are the Laetoli footprints?
- Found in Tanzania and dated to 3.4 million years ago
- This revelation indicated that Lucy walked with a modern type of bipedalism
What is Australopithecus africanus?
- Found in south Africa and dated to 2.2 - 3 million years ago
- Postcrania similar to afarensis
- Smaller canines and incisors
- Larger molars (chewing adaptation?)
- “Taung baby”
How did Australopiths grow?
Grow fast like apes. We can figure this out with dental eruption sequence and rates of enamel growth
What is Australopithecus garhi?
- Found 2.5 million years ago in Adar, Ethiopia
- Larger molars and premolars than africanus
- Associated with cut marked animal bones (butchery, hunting, stone tools)
What is Australopithecus sediba?
- 1.8 - 2 million years ago in south Africa
- Fully bipedal but still somewhat arboreal
- Human like face and teeth, small brain
- Maybe descended from africanus
What is Paranthropus aethiopicus?
Found in lake Turkana, Kenya and dated to 2.5 million years ago
What is Paranthropus boisei?
Found in east Africa with Homo habilis and dated to 1.3 - 2.2 million years ago
