2. CONTENTS OF THIS PRESENTATION
● Introduction
● Anatomy of Skull
● Sexual Dimorphism
● Significance in Forensic Investigation
● Sexual Dimorphism(Traits or Cranial Features)
3. DETERMINATION OF SEX FROM SKULL
INTRODUCTION
Skull sex determination involves assessing morphological
features of the skull to identify biological sex. This includes
examining characteristics such as brow ridge prominence,
mastoid process size, glabellar region, orbital rim shape,
overall size, and robustness. These features exhibit sexual
dimorphism, with males typically having larger and more
robust skulls compared to females. Population-specific
variations and statistical methods may also be used.
4. ANATOMY OF SKULL
The cranium, or skull, is composed of 22 bones anis d divided into two regions: the
neurocranium (which protects the brain) and the viscerocranium (which forms the face).The skull
also supports tendinous muscle attachments and allows neurovascular passage between
intracranial and extracranial anatomy. The skull is embryologically derived from mesoderm and
neural crest and will fuse, harden, and mold from gestation through adulthood. It gives the
human face its form, and even minor variations in anatomy among individuals can lead to vast
differences in appearance.In addition, it supports the muscles of the face and scalp by providing
muscular and tendinous attachment.There are 14 facial bones with specific anatomical landmarks
and embryologic development mechanisms.Embryologically, the skull derives from ectodermal
neural crest and mesoderm. The frontal, ethmoid, and sphenoid bones derive from the neural
crest, while the parietal and occipital bones originate from the mesoderm. The temporal bones
derive from both the mesoderm and neural crest, while the parietal and occipital bones originate
from the mesoderm.
5. Anterior view is the front view of
human skull.
Anterior View
Frontal Bone
Lacrimal Bone
Zygomatic Bone
Maxilla
Mandible
Nasal cavity
Vomer
Glabella
Supraorbital ridge
Orbital
cavity
6. Lateral view is the side view of
human skull.
Lateral view
Frontal Bone
Zygomatic arch
Zygomatic Bone
Maxilla
Mandible
Nasal cavity
Glabella
Supraorbital ridge
Orbital
cavity
Parietal bone
Occipital bone
Temporal bone
Lacrimal
bone
7. Inferior view is from the downside
of human skull.
Inferior view
Foramen magnum
Zygomatic arch
Maxilla
Mandible
Nasal
aperture
Glabella
External occipital
ptrotuberence
Parietal bone
Occipital bone
Temporal bone
8. Inferior view is from the
backside of human skull.
Posterior view
Foramen magnum
Zygomatic arch
Parietal bone
Mandible
Saggital
sutures
External occipital
potrotuberence
Foramen
magnum
Occipital bone
9. Sexual Dimorphism
• Sexual dimorphism in the skull refers to the differences in size, shape, and structure between male and female skulls within a
species. In humans, these differences can be observed in various cranial features and are influenced by genetic, hormonal,
and environmental factors. Some key aspects of sexual dimorphism in the human skull include:
• Overall Size: Male skulls tend to be larger and more robust than female skulls. This difference in size is particularly evident
in features such as cranial capacity and external dimensions.
• Brow Ridge: Males often have more prominent and robust brow ridges (supraorbital ridges) compared to females. These
ridges are the bony protrusions located above the eye sockets.
• Mastoid Process: The mastoid process, a bony projection located behind the ear, tends to be larger and more pronounced
in males compared to females.
• Glabellar Region: The glabellar region, the area between the eyebrows and above the nose, is often more pronounced in
males.
• Orbital Rims: Male orbital rims tend to be more squared, while female orbital rims are generally rounded.
• Sagittal Crest: In some populations and in certain age groups, males may develop a sagittal crest, a ridge of bone along the
midline of the skull, which is generally absent in females.
• Temporal Lines: The temporal lines, which mark the attachment points for temporal muscles, may be more pronounced in
males compared to females.
• Facial Features: While the skull predominantly exhibits sexual dimorphism, differences in facial features such as jaw size,
chin shape, and overall facial proportions may also be observed.
• These differences in skull morphology between males and females are important in various fields, including anthropology,
forensic science, and evolutionary biology. Analyzing sexual dimorphism in the skull can aid in sex determination from
skeletal remains and provide insights into biological differences between males and females within a population.
10. OF SKULL IN FORENSIC
INVESTIGATION
SIGNIFICANCE
The human skull holds significant importance in forensic investigations for several reasons:Identification: The skull can be crucial in
identifying human remains. Dental records, cranial features, and facial reconstruction techniques can be used to establish the
identity of a deceased individual, especially when other parts of the body are unavailable or decomposed.
• Age Estimation: Various methods, such as cranial suture closure and dental development, can help estimate the age of an
individual based on their skull. This information is valuable in forensic cases where the age of the deceased is unknown.
• Sex Determination: Sexual dimorphism in the skull allows forensic anthropologists to determine the biological sex of an
individual. This determination is essential for building the biological profile of the deceased and can aid in narrowing down
potential matches in missing persons cases.
• Trauma Analysis: Examination of the skull can reveal evidence of trauma, such as fractures or bullet wounds. Forensic experts
can analyze these injuries to determine the cause and manner of death, aiding in criminal investigations.Personal Identification:
Unique features of the skull, such as cranial anomalies or surgical implants, can help in the personal identification of individuals.
Comparing ante-mortem medical records or radiographs with post-mortem findings on the skull can assist in confirming the
identity of the deceased.
• Facial Reconstruction: In cases where the identity of a deceased individual is unknown, forensic artists can create facial
reconstructions based on the features of the skull. These reconstructions serve as visual representations to aid in identification
efforts
• Ancestral Background: Certain cranial characteristics, such as skull shape and morphology, can provide insights into the
ancestral background of an individual. This information can be useful in forensic investigations to help narrow down potential
matches or identify population affinities. Overall, the human skull is a critical component in forensic investigations, providing
valuable information for establishing identity, determining cause of death, and aiding in criminal investigations.
11. Difference between MALE and FEMALE skulls
Traits or Cranial
features
Male skull Female skull
Size and shape Larger,heavier,rough
contour.
Smaller,lighter,smooth
contour.
Cranial capacity 10% more capacity. 10% less capacity.
Glabella More prominent. Less prominent.
Supraorbital ridge More prominent. Less prominent.
Orbital cavity Squarish in shape,smooth
edges.
Almost circular or oval in
shape,sharp edges.
Zygomatic arch Extends beyond auditory
meatus.
Usually do not extend
beyond auditory meatus.
Occipital protuberence Prominent and hooked
shape.
Smooth edges.
Foramen and magnum Larger. Smaller.
Mandible Squarish in shape,less
obtuse.
Squarish in shape,more
obtuse.
12. Glabella less
prominent.
Supraorbital ridge
less prominent.
Orbital cavity almost
circular with sharp
edges.
Mandible more
pointed
Supraorbital ridge
more prominent.
Orbital cavity squarish
with smooth edges.
Mandible wider
Glabella more
prominent.
MALE SKULL FEMALE SKULL
13. Glabella less
prominent.
Supraorbital ridge
less prominent.
Orbital cavity almost
circular with sharp
edges.
Mandible more
pointed
Supraorbital ridge
more prominent.
Orbital cavity squarish
with smooth edges.
Mandible wider
Glabella more
prominent.
MALE SKULL FEMALE SKULL
Zygomatic arch
extends beyond
auditory meatus.
Zygomatic arch do
not usually extend
beyond auditory
meatus.
14. Not wide and broad
in overall size and
shape.
Mandible more
pointed
Mandible wider
Wide and broad in
overall size and
shape.
MALE SKULL FEMALE SKULL
Occipital
protuberance
prominent and
hooked shape.
Occipital
protuberance with
smooth edges.
