The differences between Men & Women

Our bones hold surprising clues to our gender. If you're a fan of investigative forensics television shows, you must be wondering how those scientists manage to distinguish gender when looking at nothing more than a bunch of bones on an examination table. The clues may not be apparent to a layperson, but a skilled professional knows exactly what to look for.

Although similar at first glance, there are subtle, but specific differences, in the male and female skeletal system. On the whole, men tend to have larger skeletons, with longer bones in the limbs and digits, a larger ribcage and wider vertebrae in a longer spinal column. This is largely due to a longer pre-pubertal growth period in boys.

The pelvis

When trying to establish the gender of an otherwise undistinguishable victim, forensic scientists and medical examiners look at the pelvic bones.

According to the US Smithsonian National Museum of National History, the pelvis is the best skeletal indicator of gender due to its distinct child-bearing features in females. Males have generally narrower pelvic features, while females have wider, shallower and more rounded pelvic features, all the better to deliver babies.

The hips

Females also have more outwardly flared hip bones. As many of these differences only manifest after puberty, younger children tend to have similar-looking pelvises and hips.

The skull

Differences between males and females can also be seen in the skull. A male skull is generally larger than a female one, with larger brow ridges and a sloping, less rounded forehead. A female skull has less pronounced brow ridges and a more vertical forehead.

The chin

Chin-wise, males tend to have a square chin and sharper jaw angle, while females have a more pointed chin and wider jaw angle.

Length, size & density

In terms of structure and make-up, the bones in both men and women are about the same. Differences in length or size may be observed between the genders, but density is not strictly greater in one or the other.

The main differences can usually be seen once age-related bone loss begins. In males, bone loss is more focused on actual bone mass, leading to the bones 'thinning out'.

In females, this loss is usually seen in the connectivity of the strands of bone. For example, more women than men experience fractures of the vertebrae, where the loss of connectivity makes these bones more vulnerable to damage, compared to other bones in the body.

As women age, their bones also become more fragile, leading to fractures. Fractures due to fragility are more common in women than in men.

References: 1. eOrthopod. Available at www.eorthopod.com. 2. Seeman E (2004). Sexual dimorphism in skeletal size, density and strength. Presented at the American Academy of Orthopaedic Surgeons 2004 Research Symposium: Influence of Sex Specificity and Gender on Musculoskeletal Health. 3. Smithsonian National Museum of Natural History. Available at www.mnh.si.edu.

*Maha bijaksana Allah.