Dimorphism # Bone Structure Jaw, Brow Ridge & Face Shape ### Overview Bone structure forms the foundation of facial dimorphism. The **jaw**, **brow ridge**, and **face shape** are the primary skeletal features that differentiate masculine from feminine faces. These features are largely determined by hormonal influences during puberty and prenatal development. ### Why It Matters Bone structure is a key category in dimorphism assessment. A strong jaw, prominent brow ridge, and angular face shape are hallmarks of masculine features, while softer contours and rounder shapes characterize feminine features. These traits influence perceived attractiveness within each gender. Research confirms that distinct facial shape differences between males and females become significantly more pronounced after puberty (Kesterke et al., 2016). ## In this category Jump to an assessment: Jaw · Brow Ridge · Face Shape Bone Structure ## Jaw Jaw width, definition, chin shape and lower face proportions ### Overview The jaw is one of the **most important** dimorphism assessments. It evaluates jaw and chin characteristics as a combined lower face assessment—including jaw width relative to cheekbones, jaw corner sharpness, lower facial third height, and chin definition. Masculine jaws are characterized by width, angularity, and strong definition, while feminine jaws tend toward softer, narrower, tapered contours. AI analysis of attractive celebrity faces confirms that attractive male faces have significantly wider jaws and chins, while attractive female faces have more tapered chins (Liu et al., 2023). ### What to Evaluate Key features to assess when evaluating jaw dimorphism: What to look for - **Jaw Width** — wider jaws relative to cheekbones appear more masculine; narrower jaws more feminine. Research shows jaw prominence is a key feature driving masculinity perceptions (Mogilski & Welling, 2018). - **Jaw Corner Sharpness** — sharper, more squared jaw corners are masculine; rounded corners are feminine. Studies found specific jaw angle measurements are preferred for both male (Mommaerts, 2016) and female (Mommaerts & Cleymaet, 2023) attractiveness. - **Lower Facial Third Height** — a taller lower face is masculine; a shorter, more petite lower face is feminine. - **Chin Width & Height** — wider, taller chins are masculine; narrower, shorter chins are feminine. - **Chin Definition** — sharper, more angular chin edges are masculine; softer, rounded edges are feminine. - **Overall Contour** — squared, angular contours are masculine; soft, tapered V-shaped contours are feminine. ### Compare Levels Compare jaw definition levels using the morph slider. Higher scores indicate stronger dimorphic expression for your gender. - Very Low (score 0–2): Minimal jaw definition with soft, rounded contours. The jawline lacks prominence and angular features. On a female face: Very angular, wide jaw with prominent width and sharp squared corners. Strong masculine bone structure. - Low (score 3–4): Below average jaw definition. Some structure visible but lacking distinct angles or width. On a female face: Angular jaw with sharper definition, wider width, and noticeable squared corners. Masculine-leaning structure. - Average (score 5–6): Moderate jaw definition with balanced proportions. Neither strongly masculine nor feminine. On a female face: Moderate jaw with balanced proportions. Neither strongly feminine nor masculine. - High (score 7–8): Well-defined jaw with clear angular features. Strong masculine presentation. On a female face: Softer jaw with gentle contours, narrower width, and rounded corners. Feminine-leaning structure. - Very High (score 9–10): Exceptional jaw definition with pronounced dimorphic features. Highly angular and well-structured. On a female face: Very soft, narrow jaw with delicate definition and rounded corners. Tapered V-shaped contour with excellent feminine structure. AverageScore 5–6 Moderate jaw definition with balanced proportions. Neither strongly masculine nor feminine. ### Tips & Warnings Important considerations when assessing your jaw: What to look for - Assess bone structure, not soft tissue or body fat - Consider your face at a neutral expression - Use good lighting that shows contours clearly Common mistakes - 01Body fat can mask underlying jaw structure - 02Lighting can dramatically affect perceived jaw definition - 03Facial hair (for males) can alter apparent jaw shape Bone Structure ## Brow Ridge Nasofrontal angle and brow bossing projection ### Overview The brow ridge is a key dimorphism assessment. It measures two main components: the **nasofrontal angle** (the angle from glabella through nasion to supratip) and **brow bossing** (forward projection of the brow bone). Masculine brow ridges have more acute nasofrontal angles and greater forward projection, while feminine brows have smoother, more obtuse angles with minimal projection. ### What to Evaluate This feature is best assessed from your **side profile**. Key features: What to look for - **Nasofrontal Angle** — the angle formed at the nasion (bridge of nose). More acute (smaller) angles indicate stronger brow ridge definition; more obtuse (larger) angles indicate a smoother, more feminine transition. - **Brow Bossing** — the forward projection of the glabella and brow bone. Greater projection creates shadow beneath the brow and is more masculine. - **Brow-to-Nose Transition** — masculine faces have a sharper break at this junction; feminine faces have a smoother, more continuous contour. ### Compare Levels Compare brow ridge prominence using the morph slider. View from the side profile for best assessment. - Very Low (score 0–2): Flat brow area with no visible ridge projection. Smooth transition from forehead to nose. On a female face: Highly pronounced brow ridge with significant forward projection. Masculine brow bone structure. - Low (score 3–4): Minimal brow projection. Slight contour but not prominently visible from side view. On a female face: Prominent brow ridge clearly visible in profile. Noticeable masculine projection. - Average (score 5–6): Moderate brow ridge development. Visible contour without extreme projection. On a female face: Moderate brow contour. Neither strongly smooth nor prominently projected. - High (score 7–8): Prominent brow ridge clearly visible in profile. Eyes appear more deep-set. On a female face: Smooth brow contour with minimal projection. Gentle transition from forehead to nose. - Very High (score 9–10): Highly pronounced brow ridge with significant forward projection. Strong masculine skeletal feature. On a female face: Very smooth brow region with no visible ridge. Elegant, refined contour with excellent feminine structure. AverageScore 5–6 Moderate brow ridge development. Visible contour without extreme projection. ### Tips & Warnings Important considerations when assessing brow ridge: What to look for - Always use your **side profile** photo for this assessment - Feel your own brow bone to understand the structure beneath the skin - Compare the projection of your brow to your forehead plane Common mistakes - 01Eyebrow hair and styling can mask the actual bone structure - 02Soft tissue thickness varies and can affect appearance - 03Expression (like squinting or frowning) alters the appearance - 04Assess the bone, not the eyebrow position or shape Bone Structure ## Face Shape Overall skull structure, facial proportions and angularity ### Overview Face shape is an important dimorphism assessment. It evaluates overall skull structure, facial height, width proportions, and face shape geometry. Masculine faces tend toward larger, more robust skulls with wider forehead and jaw regions and square-like shapes. Feminine faces tend toward smaller, more delicate skulls with narrower proportions and oval-like shapes. Research using 3D facial scans confirms these sex-specific differences emerge early in childhood and intensify after puberty (Kesterke et al., 2016). ### What to Evaluate Evaluate these aspects of your overall face shape: What to look for - **Skull Size & Robustness** — larger, more robust skulls are masculine; smaller, more delicate skulls are feminine. - **Facial Height** — taller facial height is masculine; shorter facial height is feminine. - **Forehead Width** — wider forehead regions are masculine; narrower are feminine. - **Jaw Width** — wider jaw regions are masculine; narrower are feminine. - **Face Shape Geometry** — square-like shapes are masculine; oval-like shapes are feminine. - **Cheekbone Prominence** — more prominent, angular cheekbones are masculine; less prominent, softer cheekbones are feminine. ### Compare Levels Compare overall face shape using the morph slider. - Very Low (score 0–2): Round, soft face shape with minimal angularity. Width approximately equal to length. On a female face: Very angular, squared face shape with prominent bone structure. Large robust skull with masculine proportions. - Low (score 3–4): Soft oval or heart shape. Some structure but predominantly curved contours. On a female face: Angular face with prominent cheekbones, wider forehead and jaw regions. Masculine-leaning structure. - Average (score 5–6): Balanced face shape with moderate proportions. Neither strongly angular nor round. On a female face: Balanced face shape with moderate proportions. Neither strongly feminine nor masculine. - High (score 7–8): Clearly angular face shape with defined structure. Noticeable length and squareness. On a female face: Softer face with less prominent cheekbones, narrower forehead and jaw regions. Feminine-leaning oval shape. - Very High (score 9–10): Highly angular, squared face shape with prominent bone structure. Excellent masculine presentation. On a female face: Very soft, rounded face with delicate bone structure. Narrow forehead and jaw with distinctly oval shape. AverageScore 5–6 Balanced face shape with moderate proportions. Neither strongly angular nor round. ### Tips & Warnings Important considerations when assessing face shape: What to look for - Pull hair back completely to see your true face shape - Consider your face at rest, without expressions - Look at the overall silhouette of your face Common mistakes - 01Body fat levels significantly affect perceived face shape - 02Hair framing can alter the apparent face shape dramatically - 03Camera angle and lens distortion affect face shape in photos - 04Assess in person with a mirror for most accurate evaluation Still need help with dimorphism/bone\_structure? Send us a message and a person will get back to you. 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