Dwarven Demographics

[Nerwen]

There is no anomaly here to explain. It just sounds like the article the original poster read was using a very simplistic, one-size-fits-all explanation for something much more complex.

[Aganzir]

Regardless of what the articles are like, I think this is a valid question. I can't think off the top of my head of any war the dwarves initiated that did not have something to do with vengeance and/or reclaiming lost property (the Nauglamir, Moria, Erebor...). I agree with pretty much everything that has been said so far, but I'd also like to add that overpopulation is a big motivator for war, and the dwarves hardly had a need to expand their habitat.

I would also argue that speaking about testosterone is irrevelant because the dwarves are not children of Ilúvatar but reflect Aulë's beauty ideal instead. If it was about testosterone, more dwarves would marry, but as it is, few but their kings and chieftains do (HoME11).

Originally Posted by Ulvenok

I wonder what a female dwarf looks like though...

The Later Quenta Silmarillion in The War of the Jewels says the following. I was very happy to see Peter Jackson included bearded dwarf women in the Hobbit film.

For the Naugrim have beards from the beginning of their lives, male and female alike; nor indeed can their womankind be discerned by those of other race, be it in feature or in gait or in voice, nor in any wise save this: that they go not to war, and seldom save at direst need issue from their deep bowers and halls.

[William Cloud Hicklin]

"I wouldn't say that there is a lack of aggressive-inducing testosterone among dwarven males, given their hirsute appearances and bulky muscles"

Maybe the Dwarves did steroids, which shriveled their 'nads?