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                            DEPARTMENT OF ANATOMICAL SCIENCES

 

                                       AN321  - FORENSIC OSTEOLOGY

 

                        RACE DETERMINATION FROM THE SKELETON

 

                                                            Laboratory

 

 

 

OBJECTIVES

 

 

Once this practical class has been completed, the student should be capable of:-

 

 

            1. Identifying and describing the characteristic non-metrical morphological

               features of the adult cranium that assist in distinguishing each of the

               following racial groups:

 

                                    Australoid                     Mongoloid

                                    Caucasoid                    Negroid

 

 

 

            2. Sorting unknown adult crania into Aboriginal or non-Aboriginal groupings

               using non-metrical morphological traits.

 

 

 

            3. Identifying non-metrical morphological features of the adult postcranial

               skeleton that may indicate Aboriginal origin.

 

 

 

            4. Carrying out various bone measurements and index calculations that are

               commonly used in direct metrical comparisons or in metrical determinations

               of race from the cranium .

 

 

 

            5. Applying the method of Larnach & Macintosh (1966) to sort Aboriginal

               from non-Aboriginal crania.

 

 

 

            6. Applying the metrical method of Giles and Elliot (1962) for racial

               discrimination of a cranium.


TEACHING MATERIALS

 

 

HANDOUTS

 

            Laboratory class notes

            Diagrams of characteristic racial types of cranium

            The Larnach & Macintosh (1966) descriptive list of 20 racial determining characteristics

            Notes and tables on the Giles & Elliot (1962) metrical method of Racial Attribution

            Craniometric points and measurements - from Jantz & Moore-Jansen (1988)

 

 

 

SPECIMENS and DEMONSTRATIONS

 

            Caucasoid crania

            Aboriginal crania

            Mongoloid crania

            Negroid cranial cast

            Standard casts for racial determination (Larnach & Macintosh 1966)

            Teeth with Carabelli's cusps

            Aboriginal postcranial skeletal material and bone & shell artifacts

            Samples of Aboriginal upper and lower jaws & teeth

 

 

EQUIPMENT

 

            Sliding calipers

            Spreading calipers

            Coordinate calipers

            Calculator


EXERCISE 1.

 

VISUAL EXAMINATION OF THE AUSTRALIAN ABORIGINAL CRANIUM

 

 

The following are regarded as characteristic morphological traits of the typical precontact Australian Aboriginal Cranium:

 

a)         Long, narrow (dolichocephaly) & low cranial vault.

b)         Keeled frontal contour of the cranial vault (gabling).

c)         Zygomatic arches visible from above (phaenozygy).

d)         Moderate to marked prominence of glabella and brow (superciliary) ridges.

e)         Well marked temporal lines.

f)          Moderate to large mastoid processes.

g)         Occipital bunning.

h)         Transverse occipital torus.

i)          Absent external occipital protuberance.

j)          Rectangular orbital cavities.

k)         Rounded orbital margin on the zygomatic bones.

l)          Short, depressed and concave nasal bones.

m)        Short and broad nasal aperture.

n)         Blunt nasal spine.

o)         Guttering of lower nasal margin.

p)         Moderate subnasal prognathism (anterior protrusion of the teeth & jaws).

q)         Edge to edge bite.

r)          Marked dental attrition.

s)         Large and deep palate.

t)          Antemortem avulsion of an upper incisor tooth.

u)         Absent dental caries.

v)         Non-obtrusive chin.

 

 

EXAMINE the Aboriginal crania provided, and RECORD in the table below the

presence (   ) or absence ( - ) of the above traits on each cranium:

 

--------------------------------------------------------------------------------------------------------------------

  Cranium :                                             Cranial Trait

    ID                        :  a : b : c :  d : e : f  : g :  h : i :  j :  k : l :  m :  n : o : p : q :  r :  s :  t  :  u :  v :

--------------------------------------------------------------------------------------------------------------------

                                :     :    :    :     :    :    :    :     :   :    :     :    :     :     :     :    :    :    :    :     :     :     :

                                :     :    :    :     :    :    :    :     :   :    :     :    :     :     :     :    :    :    :    :     :     :     :

--------------------------------------------------------------------------------------------------------------------

                                :     :    :    :     :    :    :    :     :   :    :     :    :     :     :     :    :    :    :    :     :     :     :

                                :     :    :    :     :    :    :    :     :   :    :     :    :     :     :     :    :    :    :    :     :     :     :

--------------------------------------------------------------------------------------------------------------------

                                :     :    :    :     :    :    :    :     :   :    :     :    :     :     :     :    :    :    :    :     :     :     :

                                :     :    :    :     :    :    :    :     :   :    :     :    :     :     :     :    :    :    :    :     :     :     :

--------------------------------------------------------------------------------------------------------------------

 

 

 

EXERCISE 2.

 

VISUAL EXAMINATION OF THE CAUCASOID CRANIUM

 

 

The following are regarded as characteristic morphological traits of the typical Caucasoid Cranium:

 

a)         A cranial vault that ranges from long, narrow & low, to short, broad & high.

b)         A rounded contour of the cranial vault (anterior view).

c)         Mild to moderate prominence of the superciliary (brow) ridges.

d)         An external occipital protuberance that is conical or hooked.

e)         Tortuous cranial sutures.

f)          Large mastoid and styloid processes.

g)         Straight (orthognathous) face.

h)         A sharp lower lateral orbital margin (on the zygomatic bone).

i)          Narrow interorbital distance.

j)          Narrow and high bridge of the nose.

k)         Depressed naso-frontal suture.

l)          Prominent nasal spine.

m)        Sharp lower margin of the nasal aperture.

n)         Deep canine fossae.

o)         Pronounced chin.

p)         Carabelli's cusps - on the mesiolingual surface of maxillary molars.

 

 

 

 

 

EXAMINE the Caucasian crania provided, and RECORD in the table below the

presence (   ) or absence ( - ) of the above traits on each cranium:

 

 

 

--------------------------------------------------------------------------------------------------------------------------

                Cranium:                                Cranial Trait

                  ID                          :  a   :  b  :  c  :  d  :  e  :  f  :  g  :  h  :  I   :  j  :  k  :  l  :  m  :  n  : o   :  p  :

--------------------------------------------------------------------------------------------------------------------------

                                                :       :      :      :      :      :    :      :      :       :     :      :     :       :      :      :      :

                                                :       :      :      :      :      :    :      :      :       :     :      :     :       :      :      :      :

--------------------------------------------------------------------------------------------------------------------------

                                                :       :      :      :      :      :    :      :      :       :     :      :     :       :      :      :      :

                                                :       :      :      :      :      :    :      :      :       :     :      :     :       :      :      :      :

--------------------------------------------------------------------------------------------------------------------------

                                                :       :      :      :      :      :    :      :      :       :     :      :     :       :      :      :      :

                                                :       :      :      :      :      :    :      :      :       :     :      :     :       :      :      :      :

--------------------------------------------------------------------------------------------------------------------------


EXERCISE 3.

 

VISUAL EXAMINATION OF THE MONGOLOID CRANIUM

 

 

The following are regarded as characteristic morphological traits of the typical Mongoloid Cranium (Chinese, Japanese, Korean, South East Asian, American Indian):

 

            a)         A flattened and broad facial skeleton.

            b)         Large prominent and angular zygomatic (cheek) bones.

            c)         A relatively short wide and high vault.

            d)         Flat glabella.

            e)         Absent or slight brow ridges.

            f)          Simple cranial sutures.

            g)         Minimal naso-frontal suture depression.

            h)         Broad and flat root of nose (wide interorbital distance).

            i)          Dull lower nasal margin.

            j)          Short nasal spine.

            k)         Absent canine fossae.

            l)          Shovel-shaped upper incisor teeth.

            m)        Short and wide palate and dental arcades.

 

 

 

 

 

 

 

EXAMINE the Mongoloid crania provided, and RECORD in the table below the

presence (   ) or absence ( - ) of the above traits on each cranium:

 

 

 

-----------------------------------------------------------------------------------------------------------

              Cranium:   :                           Cranial Trait

                ID         :   a   :   b   :   c   :   d   :   e   :   f   :   g  :   h  :   i  :   j   :   k   :   l   :   m   :

-------------------------------------------------------------------------------------------------------  ----

                             :         :        :        :        :        :       :       :       :      :      :        :       :         :

                             :        :        :        :        :        :       :       :       :      :      :        :       :         :

-----------------------------------------------------------------------------------------------------------

                             :        :        :        :        :        :       :       :       :      :      :        :       :         :

                             :        :        :        :        :        :       :       :       :      :      :        :       :         :

-----------------------------------------------------------------------------------------------------------

                             :        :        :        :        :        :       :       :       :      :      :        :       :         :

                             :        :        :        :        :        :       :       :       :      :      :        :       :         :

-----------------------------------------------------------------------------------------------------------

 

 

 

 

 

EXERCISE 4.

 

VISUAL EXAMINATION OF THE NEGROID CRANIUM

 

 

The following are regarded as characteristic morphological traits of the typical Negro Cranium:

 

            a)  A long and narrow cranial vault.

            b)  Bregmatic depression.

            c)  Rounded forehead (anterior & lateral views).

            d) Wide interorbital distance

            e) Wide rounded nasal aperture

            f). Little or no depression of the nasofrontal suture.

            g) Marked prognathism (anterior protrusion of the jaws).

 

 

 

 

 

 

 

 

 

 

 

 

Examine the Negro cranial cast provided, and RECORD in the table below the

presence (   ) or absence ( - ) of the above traits on each cranium:

 

 

                        -----------------------------------------------------------------

                          Cranium                                    Cranial Trait

                            ID                :  a   :   b   :   c   :   d   :   e   :   f   :   g   :  

                        -----------------------------------------------------------------

                                                :       :        :        :        :        :       :       :

                                                :       :        :        :        :        :       :       :

                        -----------------------------------------------------------------


EXERCISE 5

 

ABORIGINAL RACE DETERMINATION FROM THE POST-CRANIAL SKELETON

 

 

Australian Aboriginal postcranial bones especially of tribal origin may display any of the following morphological characteristics:

 

                        - relatively gracile long bones.

 

                        - squatting facets on the anterior distal tibia or

                          associated dorsum of the neck of the talus.

 

                        - tibial retroversion and retroflexion.

 

                        - anteroposterior flattening of the proximal femoral shaft (platymeria).

 

                        - mediolateral flattening of the tibial shaft (platycnemia).

 

                        - disarticulation trauma, especially associated with joints.

 

                        - chopped shafts of long bones (mortuary inquisition).

 

                        - bone arrangements into bundles.

 

                        - ochre staining of bones.

 

                        - heat effects on bone.

 

                        - forearm injuries (from tribal battles).

 

 

 

 

Examine the specimens of Aboriginal postcranial material supplied for examples of the above traits.


EXERCISE 6.

 

METRICAL EXAMINATION OF THE ABORIGINAL CRANIUM

 

 

 

Using the spreading, sliding and coordinate calipers as appropriate, MEASURE

& RECORD (in mm) the following measurements on each cranium provided:

 

 

Cranial ID No                                                                          (.........)    (.........)   (.........)

 

 

Cranial Parameter                                                                           Measurement (mm)

 

Cranial Length                                      (1)        (CL)                 (.........)    (.........)   (.........) 

Cranial Breadth                                                (2)        (CB)                (.........)    (.........)   (.........) 

Maximum Bizygomatic Diameter           (3)        (MBD)             (.........)    (.........)   (.........) 

Basion-Bregmatic Height                      (4)        (BBH)              (.........)    (.........)   (.........)

Basion-Nasion Length                          (5)        (BNL)              (.........)    (.........)   (.........) 

Basion-Prosthion Length                       (6)        (BPL)               (.........)    (.........)   (.........)

 

Maximum Palatal Breadth                     (7)        (MPB)             (.........)    (.........)   (.........) 

Maximum Palatal Length                       (8)        (MPL)              (.........)    (.........)   (.........) 

Nasion-Prosthion Height                       (10)      (NPH)              (.........)    (.........)   (.........) 

Minimum Supraorbital Breadth              (11)      (MnSB)            (.........)    (.........)   (.........) 

Maximum Supraorbital Breadth (12)      (MxSB)            (.........)    (.........)   (.........)    

Nasal Breadth                                      (14)      (NB)                (.........)    (.........)   (.........) 

Nasofrontal Articulation Width              ( -  )     (NFW)             (.........)    (.........)   (.........)

 

Frontal Chord                                       (19)      (FC)                 (.........)    (.........)   (.........) 

Frontal Subtense                                   ( -  )     (FS)                 (.........)    (.........)   (.........) 


EXERCISE 7.

 

CALCULATION OF CRANIAL INDICES & MODULES

 

 

From the measurements obtained in the previous exercise CALCULATE & RECORD for each cranium the indices and other parameters listed below:

 

                                                                                                CB    x  100

                        a) Cephalic Length/Breadth Index :      ---------------

                                    (Cephalic Index)                                CL

 

                                                                                                BBH  x  100

                        b) Cranial Length/Height Index:             ---------------

                                                                                             CL

 

                                                                                     BBH  x  100

                        c) Cranial Breadth/Height Index:            ---------------

                                                                                            CB

 

                                                                                    MPB  x  MPL

                        d) Palatal Module:                                ----------------

                                                                                            100

 

                                                                                    FS   x  100

                        e) Frontal Curvature Index:                   ------------

                                                                                                      FC

 

 

                        f)  Post-orbital Constriction:             MxSB - MnSB

 

 

 

 

                        --------------------------------------------------------------------------

                          Cranium         :               Cranial Index/Parameter

                            ID   :    a      :     b    :     c     :     d    :     e     :     f     :

                        --------------------------------------------------------------------------

                                    :           :           :           :           :           :           :

                                    :           :           :           :           :           :           :

                        --------------------------------------------------------------------------

                                    :           :           :           :           :           :           :

                                    :           :           :           :           :           :           :

                        --------------------------------------------------------------------------

                                    :           :           :           :           :           :           :

                                    :           :           :           :           :           :           :

                        --------------------------------------------------------------------------


EXERCISE 8.

 

METRICAL EXAMINATION OF THE CAUCASIAN CRANIUM

 

 

Using the spreading, sliding and coordinate calipers as appropriate, MEASURE & RECORD (in mm) the following measurements on each cranium provided:

 

 

Cranial ID No                                                                        (.........)    (.........)   (.........)

 

 

Cranial Parameter                                                                 Measurement (mm)

 

Cranial Length                                      (1)        (CL)                 (.........)    (.........)   (.........) 

Cranial Breadth                                                (2)        (CB)                (.........)    (.........)   (.........) 

Maximum Bizygomatic Diameter           (3)        (MBD)             (.........)    (.........)   (.........) 

Basion-Bregmatic Height                      (4)        (BBH)              (.........)    (.........)   (.........)

Basion-Nasion Length                          (5)        (BNL)              (.........)    (.........)   (.........) 

Basion-Prosthion Length                       (6)        (BPL)               (.........)    (.........)   (.........)

 

Maximum Palatal Breadth                     (7)        (MPB)             (.........)    (.........)   (.........) 

Maximum Palatal Length                       (8)        (MPL)              (.........)    (.........)   (.........) 

Nasion-Prosthion Height                       (10)      (NPH)              (.........)    (.........)   (.........) 

Minimum Supraorbital Breadth              (11)      (MnSB)            (.........)    (.........)   (.........) 

Maximum Supraorbital Breadth (12)      (MxSB)            (.........)    (.........)   (.........)    

Nasal Breadth                                      (14)      (NB)                (.........)    (.........)   (.........) 

Nasofrontal Articulation Width              ( -  )     (NFW)             (.........)    (.........)   (.........)

 

Frontal Chord                                       (19)      (FC)                 (.........)    (.........)   (.........) 

Frontal Subtense                                   ( -  )     (FS)                 (.........)    (.........)   (.........) 


EXERCISE 9.

 

CALCULATION OF CRANIAL INDICES & MODULES

 

 

From the measurements obtained in the previous exercise CALCULATE & RECORD for each cranium the indices and other parameters listed below:

 

                                                                                                CB    x   100

                        a) Cephalic Length/Breadth Index :       ---------------

                                                                                            CL

 

                                                                                                BBH  x  100

                        b) Cranial Length/Height Index:             ---------------

                                                                                              CL

 

                                                                                    BBH  x  100

                        c) Cranial Breadth/Height Index:            ---------------

                                                                                             CB

 

                                                                                    MPB  x  MPL

                        d) Palatal Module:                                 ----------------

                                                                                            100

 

                                                                                    FS     x   100

                        e) Frontal Curvature Index:                    ------------

                                                                                         FC

 

 

                        f) Post-orbital Constriction:                   MxSB - MnSB

 

 

 

 

                        -------------------------------------------------------------------

                          Cranium         :               Cranial Index/Parameter

                            ID   :    a      :     b    :    c      :     d    :     e     :     f     :

                        -------------------------------------------------------------------

                                    :           :           :           :           :           :           :

                                    :           :           :           :           :           :           :

                        -------------------------------------------------------------------

                                    :           :           :           :           :           :           :

                                    :           :           :           :           :           :           :

                        -------------------------------------------------------------------

                                    :           :           :           :           :           :           :

                                    :           :           :           :           :           :           :

                        -------------------------------------------------------------------


EXERCISE 10.

 

SORTING ABORIGINAL FROM NON-ABORIGINAL CRANIA

 

The Larnach & Macintosh (1966) Method for Distinguishing between Aboriginal and non-Aboriginal crania.

 

 

Use the list of 20 characters provided below and ASSESS & RECORD the appropriate values for each character in the table (page 13) using the measurements, and the casts and diagrams provided.

 

 

 

 

 

 1.        Cephalic Index:                         3 = < 75; 2 = 75 to 80; 1 = > 80

 2.        Glabella:                                    1 = < Martin's Grade 4; 2 = Martin's Grade 4;

                                                            3 = > Martin's Grade 4

 3.        Superciliary Ridges:                   1,2,3 according to standard casts

 4.        Zygomatic Trigone:                    1,2,3 according to standard casts

 5.        Phaenozygy:                              0 = absent; 1 = trace;     3 = distinct

 6.        Vault Gabling                            0 = absent; 1 = trace;     3 = distinct

 7.        Forehead Slope                         1 = > 24.7; 2 = 23.5 to 24.7; 3 = < 23.5

 8.        Occipital Torus                          0 = absent; 1 = trace;     3 = distinct

 9.        Palatine Torus                           0 = absent; 1 = trace;     3 = distinct

10.        Rounded Orbital Border on Malar Bone:

                                                            0 = absent; 1 = trace;     3 = distinct

11.        Subnasal Prognathism:               1,2,3 according to standard casts

12.        Anterior Nasal Spine:                 3 = < Broca Grade 3; 2 = Broca Grade 3;

                                                            1 = > Broca Grade 3

13.        Maximum Supraorbital Breadth: 1 = < 104mm; 2 = 104 to 108mm;

                                                                        3 = > 108mm

14.        Size of Palate:                           1 = module < 35; 2 = module 35 to 39;

                                                            3 = module > 39

15.        Naso-frontal Articulation Width: 1 = < 10mm;  2 = 10 to 12mm; 3 = > 12mm

16.        Median Frontal Ridge:                0 = absent; 1 = trace;     3 = distinct

17.        Parietal Bossing:                        1 = prominent; 2 = medium; 3 = slight

18.        External Occipital Protuberance:            3 = absent; 1 = trace; 0 = distinct

19.        Lower Nasal Margin:                 0 = anthropine; 1 = ambiguous form;

                                                            3 = distinctly non-anthropine

20.        *Post-orbital Constriction:          1 = < 16mm; 2 = 16 to 18mm; 3 = >18mm

 

 

            * NOTE: The minimum post-orbital breadth is taken on the fronto-sphenoidal

                    suture.


SORTING ABORIGINAL FROM NON-ABORIGINAL CRANIA (cont.)

Results of the Larnach & Macintosh (1966) Assessment

----------------------------------------------------------------------------------------------------------

   Cranial Trait  :                       Cranial Identification & Score

                                    :   ID…….       :   ID…….       :    ID.……      :    ID…….

----------------------------------------------------------------------------------------------------------

            1                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            2                      :                       :                       :                       :

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            3                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            4                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            5                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            6                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            7                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            8                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            9                      :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            10                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            11                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            12                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            13                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            14                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            15                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            16                    :                       :                       :                       :

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            17                    :                       :                       :                       :

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            18                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            19                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

            20                    :                       :                       :                       :

----------------------------------------------------------------------------------------------------------

TOTAL SCORE          :                       :                       :                       :

---------------------------------------------------------------------------------------------------------

EXERCISE 11.

 

ATTRIBUTION OF RACE BY METRICAL MEANS

 

Application of the Giles and Elliot Formulae for Racial Determination

 

 

READ the attached photocopy on racial attribution by metrical means taken from Stewart (1979) and based on Giles and Elliot (1962).

 

NOTE the seven measurements used by Giles and Elliot for distinguishing between the skulls of Blacks and Whites.

 

 

SELECT the appropriate measurements for Aboriginal and Caucasian crania obtained in Exercises 6 and 8 and INSERT the results into the table below:

 

    -------------------------------------------------------------------------------------------------------------------------------------------

                  Cranium               :                          Cranial Measurement                                               :          Sum of

                    ID                        :               :               :               :               :               :               :               :   Weighted Products

    -------------------------------------------------------------------------------------------------------------------------------------------

                                                :               :               :               :               :               :               :               :               -

                                                :               :               :               :               :               :               :               :               -

                                      ----------------------------------------------------------------------------------------------------------------

                            Weighted :                :               :               :               :               :               :               :

                            Parameter : :               :               :               :               :               :               :

---------------------------------------------------------------------------------------------------------------------------------------------

 

 

 

    -------------------------------------------------------------------------------------------------------------------------------------------

                  Cranium               :                          Cranial Measurement                                               :          Sum of

                    ID                        :               :               :               :               :               :               :               :   Weighted Products

    -------------------------------------------------------------------------------------------------------------------------------------------

                                                :               :               :               :               :               :               :               :               -

                                                :               :               :               :               :               :               :               :               -

                                      ----------------------------------------------------------------------------------------------------------------

                            Weighted :                :               :               :               :               :               :               :

                            Parameter : :               :               :               :               :               :               :

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Now using these metrical results, multiply each by the appropriate discriminant function weighting, and sum the products. Assume that the crania are males.

 

 

Does your result discriminate the Aboriginal cranium from the Caucasoid cranium? If not, Why?


REFERENCES

 

 

Giles E & O Elliot 1962 "Race Identification from Cranial Measurements". J. For. Sci, 7:152.

 

Jantz RL & PH Moore-Jansen 1988 A Database for Forensic Anthropology: Structure, Content and Analysis. Report of Investigations No 47, Department of Anthropology, The University of Tennessee.

 

Larnach S & NWH Macintosh 1966  The Craniology of the Aborigines of Coastal New South Wales. Oceania Monographs, 13, Sydney

 

Stewart TD  1979. Essentials of Forensic Anthropology. CC Thomas Publishers