Question about roosters

[Bryce Thomas]

I know that roosters have an instinct to be aggressive, but why are some aggressive and others not? I gave away my rooster Koa and am rooster-less, but his son Hitler was always an ass and aggressive. I treated Hitler with the same love and care as I did with koa when he was a baby and he grew up to be mean and slaughtered because of his aggression, but Koa was always an angel.
So why are some aggressive and some not? Even with the same care? Am curious.

 

[JacinLarkwell]

Same reason all animals, including people, fluctuate. It's partially genetic, partially how they're raised and partially just the individual

 

[aldarita]

They are like a box of chocolates, you never know what you're gonna get

 

[Waffle Wattles]

I held on to our extra roosters until a raccoon killed them and they were all very different.

The alpha was an insane freak and always attacked me. Was a shame because he was a beautiful roo. I would dispense soaked feed with a wooden spoon and he would attack me. There were 6 other roosters.

One day I whacked him in the head with the spoon, a little too hard, wasn't a decision but a reaction. He lost balance from it and got stumbly. Immediately the number two roo mounted him and looked like was going to kill him so I got him off and extracted the dazed roo.

He recovered fine and somewhat recovered his status.

What was interesting is he continued to attack me in the future. And when he did, some of the other roos would try and stop him, and he would fight them and they would fight back.

Then one day they were all dead.

Except for one I couldn't find. His name was Mystery Dude. He was just there one morning before we separated the roos and hens. Head count showed an extra chicken. Who was he?

He was the only chicken I didn't find after the slaughter. I miss those roos. I was going to keep as many as I could and try and get them a flock of their own but it didn't happen.