WEEK 4 STUDY GUIDE Flashcards
Hadar
First hominin fossil found, knee joint
Lucy
- Discovered by Donald Johanson and Tom Gray, 1974, Hadar, Ethiopia
- Australopithecus afarensis belonging to hominid family (which humans belong, humans and Lucy share a taxonomy up to point of genus and species)
- Lived 3.5 mya
- Related to both humans and apes
- Receding forehead, prominent face (like an ape)
- Knee joint (like a human), bipedal
- Use free hands to gather food
- Diet consisted of fruit, small animals, bird eggs, insects
- Used a blade of grass to extract termites (more advance use of hands)
Australopithecus afarensis
- Lucy
- 3.9-3 mya
- Apelike face low forehead, bony ridge over eyes, flat nose, no chin | protruding jaws, large back teeth
Cranial capacity: 375-550 cc
- Similar to chimpanzee, except for human-like teeth
- Canine teeth smaller than modern apes, larger and pointed than humans, shape of jaw between rectangular shape of apes and parabolic shape of humans
- Pelvis and leg bones far more closely resemble those of modern humans, bipedal
- Bones show they were very strong
- Sexual dimorphism
Laeoli
- Northern Tanzania, Laetoli
Leakeys, 1930 - Didn’t find any tools, so thought no humans were there
- 1975, 1976 began to find human fossils
- Fragments of hominis look similar to findings in Hadar, Ethiopia
Layer of volcanic ash that contained imprints of various animals and hominin ancestors - Footprint Tuff, 18,000 prints, dated 3.6 million years (found near volcano Sadiman | volcanic ash)
Dental arcade
shape made by rows of teeth in upper jaw
Sexual dimorphism
Sexual dimorphism, the differences in appearance between males and females of the same species, such as in colour, shape, size, and structure, that are caused by the inheritance of one or the other sexual pattern in the genetic material.
Sterkfontein
- Africanus
- No crest
- Prognathic, projecting
- Oval Brain case
- Site Sterkfontein (“Strong Fountain”)
- South African Grasslands
- Dry winters
- Robert Broom & John Robinson
- Used dynamite charges
- Mrs. Ples discovered, - Skull found (in two pieces)
- Treated acetic acid, strong vinegar-like acid
- To etch away limestone and get closer to fossil
- One of the clues to environment is Microfauna
- Other remains
Fossilized rodent femur, or owl pellet
An example of fossil with in breccia
- Adult Australopithecus, 2 million year old plus teeth
- No cavities
- Beautifully preserved
Swartkrans
- robustus
- Sagittal Crest
- Orthognathic, Flat face, Dish-shaped face, sunken in
- Cannot see nasal bones
- Thick cheek bone, zygomatic arch
- 530 cc
- Very deep mandibles, powerfully built, very thick
- ## Reflects dietCheek teeth, premolars and molars
Back: grinding
robust
Anterior teeth, cornerstone, canine and incisors
Front: cutting
Reduced
- Robust ascending ramus
Attaches to temporalis muscles
Rounder in Brain case
Kromdraii
Fossil-bearing breccia-filled cave
Karst topography
- Subterranean caves
- Fossils fall through a shaft
- Visited frequently by human
- Water, vegetation
Cave breccia
Sediments in cave - Not a nice stratigraphy like in East Africa (think of an hourglass)
- Difficult to name time periods and age
- Hominins not living here
Cemented
Not related to tectonics
Mrs. Ples
- most complete, undistorted A. africanus skull ever found
- quibble over whether fossil is really a he or a she
- smalls sized canine
Breccia
- rock consisting of angular fragments cemented together
Taung baby
- First fossil given Australopithecus africanus
- Only human fossil in Taung
- No ape-like brow
- No projecting face
- Foramen magnum, located at bottom of upright creature
Endocast
- Water moved in fine grain sediments and filled brain case, bears cranulation of brain
- Layers of enamel, like tree rings, age can be established
3 or 4 years old when died
Australopithecus africanus
- Mrs. Ples
- Cranial capacity of 440 cubic centimeters
STS-5
- Fifth hominin found at Sterkfontein
- Discovered on 1947, Robert Broom & John Robinson
- Larger incisors
- Bulbous molars and premolars
- No crest on top of heads
Australopithecus robustus
- Broom at Kromdraai, South Africa (transvaal region)
- Recovered parts of skull
Mandible
Ankle
Paranthropus “Toward Man” | Now replaced with Australopithecus robustus
Swartkrans
- Subterranean caves
- Broom and Robinson found treasure trove of fossils
- Built jaws
- Large teeth
- Heavily built skulls
- Paranthropus crassidens subsumed under Australopithecus
Enamel thickness
- Robust
Adaptation to diet
Hardest substance of mammal is enamel
- When enamel wears down dentine shows
