Intro to Paleoanthropology/Australopithecines Flashcards
What is paleoanthropology?
The study of fossils of early primates and their relatives to understand where humans came from.
What are the physical features of a primate’s hind and fore limbs? (2)
Made for flexibility and mobility.
What are the physical features of a primate’s clavicle?
Provides anchor points for ligaments.
What are the physical features of a primate’s teeth? (2)
Teeth are made for a flexible, omnivorous diet. The teeth show what they ate.
What are the physical features of a primate’s hands? (4)
Flexible, with 5 digits per hand. Opposable thumbs, broad/flat nails (instead of claws)
What does prehensile mean in relation to primate’s hands?
Grasping
What are the result of dermal ridges on a primate’s hands?
Provides fingerprints
What are the physical features of a primate’s eyes?
Forward facing eyes with stereoscopic vision.
What are brain traits associated with primates? (2)
Larger area dedicated to vision, large brain is sized relative to body size.
What is bipedalism?
Walking on two feet.
What are the pros of bipedalism? (4)
See over tall grass for food/safety, keep hands free for carrying things (baby, food, etc), more efficient long-distance travel, regulate body temperature. (less sun/more wind)
What are the cons of bipedalism? (4)
Always “falling” (always on one leg), getting oxygen to brain, stress on joints of lower body, challenges of child birth.
What anatomical changes occur with bipedalism? (6)
Foramen magnum, spine curvature, arm to leg ratio, pelvis, angle of knees, feet.
What anatomical changes occur with bipedalism concerning the foramen magnum?
(big hole in skull) In humans, bottom of skull. In animals like horses, dogs, etc, back of skull
What anatomical changes occur with bipedalism concerning the curvature of the spine?
(subtle curve in spine in lower back) Humans, curve is like a spring. Non-bipedals, none seen.
What anatomical changes occur with bipedalism concerning the arm to leg ratio?
Humans, legs are shorter than arms. Non-bipedals, sizes are comparable.
What anatomical changes occur with bipedalism concerning the pelvis?
Humans, short/broad. Apes, tall/slender
What anatomical changes occur with bipedalism concerning the angle of the knees and feet/hands? (3)
The angle of the knees change. Hands are similar, but Humans do not have a separate curve that is not relative to the joints. Toe difference is obvious, as humans do not have any toes out of line.
Who are the Australopithecines?
(“Southern Ape Man”)
When/where were the Australopithecines found?
1-4 MYA in Africa
Why are the Australopithecines important? (2)
First evidence (fossil) of bipedalism, retention of evidence of climbing.
Name 4 features of Gracile Australopithecines.
Lighter build (thinner, more delicate) More petite Smaller teeth Lighter facial/dental musculature
What are the two species of Gracile Australopithecines?
Australopithecus Afarensis and Australopithecus Africanus
When/where were the Australopithecus Afarensis found?
3-4 MYA in East Africa
What are the key physical features of the brain of Australopithecus Afarensis?
Brain is small (440cc), but still large in relation to body size- size of a softball.
What are the key physical features of the teeth of Australopithecus Afarensis?
Thick enamel on molars, more ape-like canines. (hard diet)
What are the key physical features of the skull of Australopithecus Afarensis?
Face projects prognanthic, base of skull flares for attachment of neck muscles.
What are the key physical features of the arms/legs and the feet/hands of Australopithecus Afarensis?
Arms and legs are about the same length, finger and toe bones curved. Feet have an arch and legs angle inward.
What are the key physical features of the pelvis of Australopithecus Afarensis?
Pelvis and leg bones show bipedal adaptation, pelvis is wide and flaring but also cup-like.
What are the two main fossil discoveries of the Australopithecus Afarensis?
“Lucy” (large canines, chimp-like skull) “First Family” (13 individuals, kids and adults)
When/where were the Australopithecus Africanus found?
2-3 MYA in South Africa
What are the key physical features of the Australopithecus Africanus?
Moderate brow ridge, 3.5-4.5 feet tall, sexually dimorphic.
How big was the brain of the Australopithecus Africanus?
428-485cc
Who discovered the Australopithecus Africanus?
Raymond Dart
What was the first Australopithecus Africanus fossil found, and how old was it?
Toung child, about 3 years old from 2-3 MYA.
How can you tell the Australopithecus Afarensis from the Australopithecus Africanus?
Cheek bones: 90 degree- Afarensis sloping- Africanus (Brow- Africanus)
Where were the Robust Australopithecus first found?
Cave sites in South Africa.
What are the two different kinds of Robust Aussies?
Australopithecus Boisei and Australopithecus Robustus
When/where were Aussie Boisei found?
1-2.3 MYA in East Africa
What species is known as the “Nutcracker Man”?
Australopithecus Boisei
Who found the Boisei first? Where?
Found by the Leaky’s in Olduvai Gorge
When/where were Aussie Robustus found?
1-2.3 MYA in South Africa
What did the Australopithecus Boisei’s diet consist of?
Coarse nuts, sees, and roots
Were robust forms thought to be directly related to modern humans?
No
What kind of dating technique was used for the Australopithecus Boisei?
K-Ar dating
What species as also referred to as a different genus, Paranthropus
Robust Australopithecines
What sets Robust Aussies apart from Gracile Aussies?
Robust have bigger teeth, in addition to a sagital crest in some.
Why are there so many different kinds of Australopithecines?
They had to adapt to different diets and environments (from leaves to seeds)
Which species of Australopithecines featured massive faces/jaws and a strong chewing apparatus?
Robust Aussies
