Download Fossil Hominid Lab

ANTH 260
Fossil Hominid Lab
Thursday, April 4, 13
Handling fossil casts
• Treat them as if they were authentic
specimens
• Use care & professional integrity
• Casts are very expensive
• Casts represent the remains of actual
individuals
• Leave casts at same table, keep over table
Thursday, April 4, 13
Anatomically speaking
• Need a fixed position
from which to make
relative references
• “Anatomical position”
Thursday, April 4, 13
Anatomical planes
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FRONTAL (or coronal) separates the body into
Anterior and Posterior parts
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MEDIAN (or midsagittal) separates body into Right
and Left parts
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HORIZONTAL separates the body into Superior
and Inferior parts
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SAGITTAL any plane parallel to the median plane
Terms of position:
•Superior (closer to the head) vs. Inferior (closer to the feet)
•Posterior/Dorsal (back side) vs. Anterior/Ventral (front side)
•Medial (closer to center) vs. Lateral (farther from the center)
•Proximal (closer to the origin of structure) vs. Distal (further
away from the origin)
Thursday, April 4, 13
Some bones: Cranial
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Cranium: skull minus lower jaw
Calvarium: skull cap, skull minus “face”
Occipital: very back of skull
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Foramen Magnum
Nuchal chrest: bump on occipital bone
Frontal: forehead, top of nose, behind eyes
Parietal: (2) top, sides
Temporal: (2) location of ears, connects to...
Zygomatic arch: (2) cheek bones
Maxilla: upper jaw
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Mental protuberance: chin
Ramus: (2) side of jaw
Sutral: form in between bones of skull, in
sutra lines
Sagittal keel (vs. sagittal crest)
Thursday, April 4, 13
Ramus
Some bones: Post-cranial
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Humerus: upper arm, largest
arm bone
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Radius: lateral forearm bone
(thumb side)
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Ulna: medial forearm bone
(pinky side)
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Contains trochlear notch
& olecranon process
Femur: upper leg bone
Tibia: shin bone
Fibula:smaller lower leg bone
Patella: knee bone
Feet:
Tarsals→Metatarsals→Phala
nges
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Big toe = Halux, only 2
Hands:Carpals→Metacarpals
→Falanges
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Thumb, only 2
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Some bones: the Pelvis
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Ilium: side hipbone
that flares up
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Ischium: “sit bones”,
has hole for leg
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Pubis: front part of
pelvis
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1/2 of a pelvis (all 3 of
above) = Innominate
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Innominate
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Thursday, April 4, 13
Obturator
foramen & sciatic
notch ~ sex
determination
Obturator foramen: ♀= small, triangular, ♂= large, oval
Sciatic notch: ♀= wide, >90°, ♂= narrow, <90°
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Dentition
Homodonts (all teeth the same) vs.
Heterodonts (differentiation of
teeth)
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All mammals and primates are
heterodonts
Dental formula: the layout of one
quadrant
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Platyrhini (New World
monkeys): 2-1-3-3
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Catarihni (Old World monkeys &
apes): 2-1-2-3
Molar patterns
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Cercopithecoidea (Old World
monkeys): X-4
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Hominoidea (apes & humans):Y-5
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Ape-Human Comparisons
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Bipedalism: 3 osteological traits
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Halux, Foramen magnum, pelvis/femur
Pelvis: Apes, long, skinny ilium; human iliums, shorter,
wider.
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Cranium: Apes, post-orbital constriction; humans, no.
Apes, low maximum skull breadth; humans, high.
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Face: Apes, prognathic (snouts); humans, orgnathic
(mouth)
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Jaw (dental arcade): Apes, rectangular; humans, parabolic
Teeth: Apes, canine shearing complex, diastema; humans,
canine reduction.
Australopiths
• At least 7 species
• Only found in Africa
• Two types:
- Gracile: Australopithecus afarensis, A.
africanus
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Robust: A. robustus, A. boisei, A. aethiopicus
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e.g. Paranthropus
Homo
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Early fossils: 2.4-1.4 MYA
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Tool use
Craniums: larger, higher, rounded
Diet & chewing: <prognathic, >orgnathic, smaller mandible,
tighter teeth
Use/control of fire (?)
First to leave Africa (?)
By 800KYA, “archaic” Homo sapiens
Neanderthals: 130KYA-30KYA
Lab assignment
• Read (skim) texts
• Complete Lab Exercises 13.2, 13.3, 14.1, 14.2
• Make comparisons relatively
• Keep big picture in mind, point is to
understand differences in fossils based on
direct observation
• Move about tables to work with all fossils
Thursday, April 4, 13