Why do black people fight so hard and so tough?

Born with physical problems, black people live in the tropics, and some wild animals, like lions and African elephants, have to fight if they want to survive, so they have evolved to be stronger from a long time ago, and fighting is more severe than Asians living in a relatively stable environment. Moreover, because Africa is poor, there is no high-tech economy and source of life, and it is mainly physical labor that exercises good physique, so as you said, Africans are really stronger.