Biological Anthropology

• Parts of the sectorial complex

  • larger upper canine, diastema, and unicuspid lower first premolar
• Dentition


  1. Procumbent incisors

  2. Tribosphenic molars

  3. Bilophodont molars

  4. Y-5 molars
• Procumbent incisors


  Diet expected: Gummivory
• Tribosphenic molars


  Diet expected: Insectivory
• Bilophodont molars


  Diet expected: Omnivory
• 1. Y-5 molars

  Diet expected: Omnivory
• IMI under 100


  Locomotive pattern: biped or vertical clinging and leaping (VCL)
• IMI over 100


  Locomotive pattern: suspensory
• IMI approximately 100


  Locomotive pattern: quadruped
• Scapula features associated with quadruped locomotion


  • Elongated horizontally
  • Laterally placed with glenoid fossa
• Pelvic girdle features associated with quadruped locomotion


  • Long and narrow
  • Shallow greater sciatic notch
• Scapula features associated with biped locomotion

  • Wider range of movement (stability instead mobility)
  • Glenoid fossa is more shallow
• Pelvic girdle features associated with biped locomotion


  • Is elongated more axially
  • Bowl-like shape
  • Deeper greater sciatic notch
• Scapula feature that distinguishes suspensory from biped

  Elongated more axially
• Pelvic girdle features associated with suspensory locomotion


  • intermediate sciatic notch
  • intermediate length and width
• Ancestral traits of Plesiadapiformes


  • Long tail
  • Flexible limbs
• Derived traits of Plesiadapiformes


  • No postorbital bar
  • Small brain
  • very prognathic
• Adapoids


  Have small eyes and a longer snout
• Omomyoids


  Have larger orbits (eyes) and a shorter snout
• Adapoids are ancestral to Strepsirrhines and Omomyoids are ancestral to Haplorhines
• Anatomical changes in anthropoids during Oligocene adaptive radiation


  • Fused frontal and mandible
  • Post-orbital closure
  • Greater sciatic notch is intermediate size
• Parapithecidae are ancestral to Platyrrhine with a dental formula of 2:1:3:3, while Propliopithecidae are ancestral to Catarrhine with a dental formula of 2:1:2:3
• Ancestral traits of Miocene apes

  • Sectorial complex present
  • No curved digits (for suspension)
• Derived traits of Miocene apes

  • Y-5 molar pattern
  • No tail
• Ancestral cranial traits of Australopithecus afarensis

  • Relatively prognathic
  • parallel dental arcade
  • No sagittal crest (globular cranium)
• Derived cranial traits of Australopithecus afarensis

  • increased encephalization
  • bipedal
• Ancestral cranial traits of Australopithecus africanus

  • Bowl-shaped pelvis (shorter & broader)
  • Foramen magnum more anteriorly placed
  • More angled femur (valgus angle)
  • flaring zygomatic arches
• Derived cranial traits of Australopithecus africanus


  • No sectorial complex
  • more parabolic dental arcade
  • less prognathic
  • smaller teeth
• Ancestral cranial traits of Australopithecus sediba

  • Zygomatic arches are less wide/flared
  • small cranial capacity
  • pretty prognathic
• Derived cranial traits of Australopithecus sediba


  • parabolic dental arcade
  • less flaring zygomatic arches
• Au. aethiopicus has the largest sagittal crest and most dished face
• Au. boisei has postcanine-megadontia (extremely large) and is hyper-robust
• Au. robustus has anterior pillars (appears the least robust out of all three compared)
• Ancestral traits of Homo habilis

  • Small brain size
  • small body size
• Derived traits of Homo habilis

  • Long/low cranial shape
  • Sagittal keel
  • less prognathic
• Ancestral traits of Homo erectus


  • Long/low cranial vault
  • Occipital bun
  • Prominent brow ridges
• Derived traits of Homo erectus

  • Large cranial capacity
  • sagittal keel
• Ancestral traits of Middle Pleistocene Homo

  • Slight sagittal keel
  • Globular/robust cranium
• Derived traits of Neanderthals

  • Large nasal aperture
  • No chin
  • Occipital bun
  • Midfacial prognathism
• Derived traits of Homo sapiens

  • Gracile/flatter face
  • Maximum cranial breadth
  • Vertical forehead