What is the deal with Baxter's hair, anyway?

Several characters change hair colors off and on through the series. Vernon Fenwick sometimes had brown hair in the earliest episodes, before it permanently switched to black. April O'Neil can flip back and forth between being a redhead and a brunette depending on the episode. Baxter, however, appears to be the only character in the series whose hair changes not only color, but style, between seasons 1 and 2.

Season 1 introduces us to a mild-mannered scientist whose hair is blond and worn in a short style that flips up slightly at the ends.

By season 2, it's a wild mass more fitting for a mad scientist, and most of the time it's light brown.

For one season 2 episode, however, it's back to a more blond color. Although the shadowed part still looks closer to the light brown, there is the interesting fact that in the other season 2 episodes, no shadow is cast; Baxter's hair remains the darker shade all the way around.

After his transformation, what's left of his hair usually, but not always, looks closer to blond.

Most fan artists, I noticed, seem to draw Baxter's season 1 look, when they draw him as human at all. I don't know whether they actually prefer it in that style and color or if they're just doing it to separate him from Barney.

I personally prefer the season 2 look, both in style and the usual color. When Baxter is transformed back into a human at the beginning of my "pilot", he is described as having long, light brown hair. This is how he will be depicted in my illustrations.

I would be curious to know why the animators chose to radically alter his design, but I could make a guess. Since the style does put one in mind of cliche mad scientists, it may very well be another indication that Baxter is meant to have gone mad in season 2, instead of still being sane.

I gave a reason in the first story as to why his hair changes style. I say that while in the asylum, he deliberately let it grow out so it would match the style Barney chose. Barney abandoned him and Baxter is bitter and hurt and wants to remind him that they are brothers. I did not explain the changing color. Perhaps it's just a trick of the light. People always tell me my hair looks black when it's really brown, and people with light brown hair can often look blond.