Sex estimation and stature

Define biological profile

A scientific assessment of skeletal remains that estimates key
identifying characteristics

What are they key identifying characteristics of skeletal remains

• Biological sex
• Stature
• Age at death
• Ancestry/population affinity
• Other identifying features; trauma, pathology

Why do we create a biological profile

Identification

• Narrow pool of possible identities
  • Disaster victim identification
  • Guide missing person searches
  • Skeletal/fragmented/damaged remains → complex

Explain how sex estimation is figured out

Dimorphic variations between male and female
skeleton

Where are the most extreme differences found between male and female?

Pelvis and skull

Describe the accuracy of sex estimation

• Not absolute
• Looks for variations
• Uses probabilities

(Features can give different estimations Even on the same individual!)

When is sex estimation most accurate?

On an adult, fully developed skeleton

inaccurate for juveniles as changes occur during puberty

How accurate is the skull?

80-90%

Describe difference between a male and female skull?

• Male = robust

• Female = gracile

What are the features of the skull used for sex identification

1. Nuchal crest
2. Mastoid process
3. Supraorbital margin
4. Supraorbital ridge/Glabella
5. Mental eminence

Describe the nuchal crest and difference in male/female

Bony ridge on occipital bone

Male → larger protrusion, rough
Female → smaller, smoother

Describe the Mastoid process and difference in male/female

protrusion at bottom of temporal bone

Male → larger, more prominent
Female → smaller, less prominent

Describe the Supraorbital margins and difference in male/female

upper orbital margins

Male → larger, thicker
Female → smaller, sharper

Describe the Supraorbital ridge/Glabella and difference in male/female

Between eyes, central on the frontal bone

Male → more prominent
Female → less prominent

Describe the Mental eminence and difference in male/female

Prominence at centre of mandible

Male → thicker, rugose
Female → smaller, gracile

Skull variations number scale explain

0-5

• 0 = undetermined sex (insufficient data available)
  • 1 = female
  • 2 = probable female
  • 3 = ambiguous sex
  • 4 = probable male
  • 5 = male

Accuracy of pelvis

90-95% accuracy

most reliable

Describe difference between male and female pelvis

• Male → narrower
• Female → wider
(Adapted for childbirth)

What features of the pelvis are used for identification

• Ilium
• Subpubic angle
• Greater sciatic notch
• Pelvic inlet
• Coccyx

Describe the Ileum and difference in male/female

Large blade-like bone

Male → less angled/curved
Female → more angled/curved flaring

Describe the Subpubic angle and difference in male/female

Front of pelvis

Male → smaller angle
Female → wider angle

Describe the Greater sciatic notch and difference in male/female

Posteriorly on the os coxae

Male → narrow
Female → wide

Describe the Pelvic inlet and difference in male/female

Top of pelvis

Male → smaller, triangular
Female → wider, oval

Describe the Coccyx and difference in male/female

Bottom of the spinal column

Male → angular
Female → less angled

What is stature estimation

The stature (height) of an individual can be
calculated using specific formulae

Whats the most accurate for stature estimation

Long bones

Leg bones (femur, tibia) → vast majority of height

Why is the accuracy slightly skewed

• Uses documented heights – people overestimate
• Assumes people are proportional

What does stature estimation require for accuracy?

biological sex estimation

How to calculate stature?

• Measure the long bone (x3)
• Locate the correct equation to use
• Consider biological sex
• Bone measured
• Input the measurement into the calculation

ALWAYS MEASURE IN MM

Formula for stature

Factor x length in mm + constant

then + and _ standard error