Transcript Hominid skull reference - Madison Public Schools

Hominid Anatomy
Key features to know
Modified from www.iupui.edu
How does evolution explain
complex organisms like
humans?
https://www.youtube.com/watch?v=oxgnlSbYLSc
Erect posture
Shape of spinal column
Skeletal implications of bipedalism
Location of foramen magnum
Bipedal Locomotion
Laetoli
Footprints
Chimp and
human foot
Femurs of upright walkers and ape
Leg of ape
Quadrupedal animals like
apes, have femurs in which
the ball joint, the part that
joins the pelvis, sits
directly over the inside of
the knee. The angle
subtended by the femur at
the knee in quadrupedal
walkers is less than that of
bipedal walkers.
Leg of Australopithecus afarensis
This diagram shows the femur
with the same shape and
structure as that of modern
humans, but it is a little shorter. It
subtends the same angle at the
knee as that of a modern human
and the inner bump of the knee
joint is larger than the outer one.
This shows that this hominin was
also a bipedal walker.
Leg of modern human
This modern Homo sapiens bone
shows the structure of the femur
of an upright walker or bipedal
animal. The ball joint, the part that
joins the pelvis, sits directly over
the outside of the knee. The angle
subtended by the femur at the
knee in bipedal walkers is greater
than that of quadrupedal walkers.
This results in the inner bump of
the knee joint being longer than
the outer bump.
Skeletal implications of bipedalism
Pelvis, femur feet
Skeletal implications of bipedalism
Chimp vs. A. afarensis
Knock-kneed walk
Pongid Prognathism.
(Line of greatest muscle force is shown in red.)
Understanding Physical Anthropology and Archaeology, 8th ed., p. 245
Satittal crests and temporal muscle orientations.
Hominid compared to pongid.
(Line of greatest muscle force is shown in red.)
Understanding Physical Anthropology and Archaeology, 8th ed., p. 245
Human and Ape Brains
Humankind Emerging, 7th ed., p. 389
The brains develop in . . .
• size
• complexity
• the ratio of brain weight to overall body
weight
Cranial Capacity
Understanding Physical Anthropology and Archaeology, 8th ed., p. 234
Cranial Capacity & Vaulted Forehead
Australopithecus afarensis
Homo (sapiens?)
neandthalensis
Homo erectus
Homo sapiens
sapiens
Teeth / Dental Arcade
Monkey & Ape Canines
Apes (and monkeys)
still possess conical,
dagger-like canines
which project well
beyond the surface of
the opposite teeth.
The gap is a diastema.
Teeth of a male patas monkey.
Understanding Physical Anthropology and Archaeology, 8th ed., p. 231
Molar
Cusp
Patterns
plus-4
Y-5
Y-5
Example of early hominid
fossil Y-5 cusp pattern molars
Dental formulae
Understanding Physical Anthropology and Archaeology, 8th ed., p. 125
Changes in dental arcade
Proconsul heseloni
19 - 17 mya
Homo erectus
500,000 - 300,000 y
Modern
Chimp
Australopithecus
africanus,2.8 - 2.3 mya
Modern homo sapiens
100,000 ya to now
Crests and other muscle attachments
Crests and other muscle attachments
zygomatic arch
Mandible and chewing
Muscle attachments
Some Important Skull Features
Modern human cranium.
Understanding Physical Anthropology and Archaeology, 8th ed., p. 510
For a nearly complete look at skulls, click on the image above for the
Australian National Museum’s web site.
Be sure to look at Becoming
Human, the Institute for Human
Origins broadband documentary
and web site.