Christopher W. Schmidt - University of Indianapolis Archeology ...

1968; Finnegan and Marcsik, 1979; Hauser and DeStefano, 1989; Houghton, 1978; Ossenberg,
1969; Rhine, 1990; Sawyer et al. 1979; Sawyer et al., 1998). Robusticity of muscle attachment
sites is included to see if body build has an effect on the expression of mandibular traits. Two of
the traits examined (mylohyoid bridging and accessory mandibular foramen) are discrete
(nominal) in nature and are scored either as “present” or “absent.” However, the other traits vary
in a gradating order and must be scored in a different manner. These ordinal traits are described
as “quasi-continuous” (Saunders, 1989) and have intermediate stages scored on a ranked scale.
Ramus inversion. In some individuals, the edge of the posterior mandibular ramus is
medially rotated (Angel and Kelley, 1990). Ramus inversion is an ordinal trait that is scored on
a four-point scale (0 to 3) for the right and left sides of the mandible separately. A score of “0”
indicates a completely straight ramus that lacks inversion. A score of “1” indicates slight
inversion. A mandible that displays a moderate amount of incurvature of the ramus is given a
score of “2.” A score of “3” indicates extreme inversion that dominates the majority of the
ramus (Parr, 2003).
Location of inversion. Both right and left rami are evaluated separately on a 3-point
ordinal scale depending on the location of greatest incurvature. A score of “0” indicates that the
greatest amount of incurvature is located in the lower third of the ramus. A mandible with
inversion that is greatest in the middle third of the ramus is given a score of “1.” A score of “2”
indicates a ramus with the greatest incurvature in the upper third of the ramus.
Gonial eversion. Gonial angle eversion is scored separately on each side using a 5-point
ordinal scale. A gonial angle displaying inversion is assigned a score of “–1.” A score of “0”
indicates a gonion aligned with the ramus and completely lacking eversion or inversion (Rhine,
1990). A mandible with slight eversion of the gonial angle is given a score of “1.” A score of
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