I have to point out for the sake of those who read this thread and have a picture of a harmonious group of mixed males and females that the reality is they all fight.
I do not know of one single keeper who observes their chickens closely who will say hand on heart their chickens always get along.

They don't. Usually the scraps are face saving, over in seconds, particularly with the females. Usually there are no injuries to speak of. Sometimes all one sees are a couple of new peck marks on the males comb and wattles. It is extremely rare that such peck marks are the result over over enthusiastic grooming for example.

If one has juveniles then one has probably seen males chest bumping; that's low level fighting and one backs off and it's all over.
Like any species, chickens have to compete for mates and resources. Some fighting is inevitable. Hopefully and usually in my experience, they manage all this better than humans and don't lose the plot and try to wipe out the entire chicken world in the process of trying to show who's boss unlike some of our so called leaders.
In the better balanced tribes and groups the seniors and hopefully wiser ones keep the violence to a minimum. but it's always there. Some chickens are just plain bullies, fighting them is inevitable at some point. I've had situations when it's not been the bullies victim that has balanced the scales so to speak, it's been a senior hen or rooster who has just lost patience with all the drama.
Young cockerels getting knocked off a hen they had managed to get to crouch for them by a senior rooster goes on all the time in a large mixed sex group. That's violence/fighting. Just because a fight may have been a one punch knockout doesn't mean it wasn't violence.