Why do giraffes have horns?

[Truncated]

Do they use them for anything? Are they perhaps just evolutionary leftovers? Why are they shaped the way they are (furry spheres on sticks)?

BTW, hello. This is my first post. :)

[Phobos]

hello! welcome to the SDMB!

This website...
http://nature-wildlife.com/girtxt.htm
has this to say about it...

Females never use their horns, and males only use theirs in contests with peers.


If I recall my nature documentaries correctly, the males bash each other with their horns in mock battles in order to establish the alpha-giraffe.

That, plus the horns help to hold their hats on. :)