Filly vs Mare

[Downthestretch55]

Originally Posted by 2MinsToPost

Why are Fillies not as "rank" as mares? Does it have to do with their bone structure, muscle structure..... why is it that they are not on the whole as "rank" as the males?

Sorry, novice question from a novice but had to ask after really cheering on that Rags to a win. That was fun and I would LOVE to see more races like that. Boy Vs Girl

Curt,
I don't think one can generalize about fillies/mares being "rank".
Just an example from my own experience, two fillies, both 2yo's.
One is very easy, the other, yikes.
Both one stall apart. Same handlers, same feed.
Just my experience, but each one is different.
Colts are a whole different story. Even a yearling colt put out with mares and fillies can get dangerous (protective) of his harem.
I've met some very nasty mares also.
So, bottom line...I don't think it's a male/female factor.