[chimeracoder]

> I've never heard of someone taking both their given last name and their married last name together as their new last name but without a hyphen.

That's actually incredibly common in Spanish-speaking parts of the world.

It used to be that women would add "de Foo", where Foo is the last name of their husband, but nowadays it's fashionable to drop the "de", because that implies ownership ("de" is the Spanish equivalent of "'s")

It actually gets way, way more complicated, but that's a tl;dr: http://en.wikipedia.org/wiki/Spanish_naming_customs

[Casseres]

From what I understand, the hyphen was introduced to last name of Spanish origin because spaces were not allowed in databases.