Ah but I'd say that anyone who 'prefers' women without make-up is not being honest with themselves. All guys I have met who do not like women with make-up are not good looking at all, and if they were honest with themselves, they would like a gf who wears make-up BUT due to their lack of looks, they do not think this is possible, and so warp "I think women with make-up are attractive, but for me, unachivable" into "I don't like women who wear make-up."
It's the exact same situation with the girls I have met who are into skinny guys and say they don't like buff guys.
Enough alcohol down the throats of either the guy or girl, and you do eventually (I have found) get the truth out of them, but people are almost all too insecure to admit this.
No scientific studies into the matter?:
http://www.independent.co.uk/life-style/love-sex/attraction/the-science-of-magnetism-926693.html
There are loads.
As for better with make-up:
http://images.google.co.uk/images?hl=en&safe=off&client=firefox-a&rls=org.mozilla:en-GB

fficial&hs=av6&um=1&ei=MfEOS_uoJ-bPjAfGytiLBA&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=celebs+without+make+up&spell=1&start=0
And again, please find me a major film scene (Hollywood) where an actor or actress has no make-up, without it being relative to the story e.g. in a prison.
Basically, if everyone was secure in their looks, nature intends them to look for healthy partners, and make-up allows women, and men I guess, to achieve this end and fulfil that subconscious desire. Only people aren't always happy with how they look and let their own looks cloud what they perceive as attractive.
For example, I have never met an attractive girl that didn't wear make-up or a good looking guy that disliked make-up. Coincidence? Doubt so.
As for the animal question, it's still f**king retarded, as make-up is developed for humans, not goats. It's like asking "If you like a polished car, what do you think about using car polish on a tree?"