Stevie Hebert - Lab 12 Answers

ANTH 2230L Lab 12 Lab 12: Proto-Hominins and Australopithecines- A N SWER SHEET Station 1 2 3 4 5 6 7 8 9 Trait Pan troglodytes Ar. Ramidus Au. afarensis Au. africanus Au. (P.) aethiopicus Au. (P.) boisei Au. sediba H. s. sapiens Mystery Skull Date range ~8 my- present 5.8-4.4 mya 4.5-2.9 mya 4.5-3 mya 3- 2.5 mya 2.5-1.5 mya 2-1.5 mya 300 kya - present ? Avg. cranial capacity 285-450 cc Unknown at present 430-500 cc 430-500 cc 410 cc 400- 510 cc 420- 450 cc 1200- 1450 cc ? Prognathism (absent, intermediate, prominent) Occipital torus (none, bony ridge, or occipital bun) Forehead shape (vertical or sloping) Location of foramen magnum (center or rear) Size of supraorbital torus (absent, small, medium, or large) Shape of chin (eminent or retreating) Shape of dental arcade (U-shaped, parabolic, intermediate) Flaring zygomatics (yes or no) Dished-out (concave) face (yes or no) Presence and size of sagittal crest little IttR prominent prominent prominent intermediate prominent to to absent prominent none none absent bony bon absent bone ridge bun abent absent en as vertical vertical vertical Vertical sloping sloping sloping vertical sloping rear center Center Center center unter center center unter medium medium large large large small small absent m man retreating retreating retreating retreating retreating retreating retreating Eminent retreating Intermediate U-shape U-shape U-shape intermediate parabolic parabolic parabolic parabolic no Yes yes ye) YS yes no no US no yes no yes yes no no no yes vm absent absent absent large medium small absent small small

(absent, small, medium, large) Canine honing or apical wear 1. Based on your observations, who is the mystery skull? Explain. Station 10: 1. Compare the model of S. chadensis, a proto-hominin, to the australopithecines and chimpanzee you observed above. How is this specimen similar and different from the chimpanzee? How is this specimen similar and different from the australopithecines? Station 11: As you chew each type of food (soft, medium, hard), feel your chewing muscles. You can place you hands on the side of your head above and behind your temples (to feel the temporalis muscles) and on your jaw near your molars (to feel the masseter muscles). 1. As you chew each type of food, describe the differences in contractions in your jaw. 2. Which teeth do you use most while chewing? 3. Which members of the human lineage do you assume would have eaten the toughest foods, based on the tooth size and jaw size? Describe any association between molar size and jaw size.