Of course, there is the plenty of precedent of all of the Normal/Flying types that exist. Every Pokemon that has been animal-like that is Flying type has always had a typing other than Flying as its primary.
Therefore, I agree that Flying should not be the only type.
As this was responding to my post, I just thought I would clarify, that I actually do support pure Flying. I think it makes a lot of sense, especially since Flying is CAP1's primary type.
Basically, what my previous post was trying to say was that the statement that pure flying denotes wind based is not true. I was trying to make the point that we do not have a large enough sample space to accurately determine what pure flying should or should not be. My last statement was trying to say that this fact does not necessarily mean it should be pure flying, but that using this fact (or lack thereof) to say it shouldn't would not be a good argument.
Once again, I would like to say that I definitely do like pure
Flying (among others), but I do not want to see it be part Normal just because it is a mammal. As I said in my first post, no matter how many times people repeat it, Mammal does not equal Normal.
EDIT:
Fair enough. If you want to look at it that way, then you could simply look at Tornadus and Arceus, who are (can in Arceus' case) be pure Flying prior to being sent into battle... The primary point being that all pure flying-types (that can be that way without the use of Skill Swap, or just the former two if you want to look at them) are wingless and thus would appear to be wind-based as a result.
However I do concede the point that those two aren't really broad enough a reference to consider the definition of pure Flying-types, I suppose.
Nonetheless I am still somewhat opposed to pure Flying as this thing's type.
Well, personally I don't even consider Arceus, as it is not based on anything flying (or fire, or water, or anything when it is that type), and Tornadus by itself is not good sample. I can understand people's hesitation due to lack of any precedent, for or against, but I am mainly trying to say that if it is going to be part Flying, it should not have to have Normal as well. Flying can be independent, and there is nothing saying a pure Flying can't be bird/mammal based.
On a different note, to those who say it shouldn't be flying because it, well, shouldn't fly, I would like to direct your attention to Doduo and Dodrio.
"A bird that makes up for its poor flying with its fast foot speed. Leaves giant footprint" -Doduo's blue Pokedex entry
Like our Pokemon, it may not be able to fly well (ours will eventually fly, so i would imagine it would at least look like it could develop the ability to fly), but that doesn't mean it can't be flying type.