[ihavedna]

It is because woman are considered to be the adjunct, not the norm, not the average, not the expected or assumed. Its even obvious in the word itself - a prefix on the word "man", which can and is often used in place of "person" or "human", and will describe a person who is more than likely assumed to be of the masculine persuasion.

A+ on not putting "Woman" in the headline for the article, though!

[Filligree]

Appearances to the contrary, the word "woman" is not actually based off "man", or indeed very related.

[iopq]

Yes, it is. It's wif-man, so a "person who is a wife" as opposed to an unmarried girl. That's why women is pronounced [wimen], because that's the original etymology.

[phaemon]

Of course it is.

    wifman = female human
    werman = male human
    man = human

"wifman" became "woman" but the "man" is literally from "man" (meaning human). I'm not sure how much more related you can get.