If you teach a child they’re no more than an evolved animal, then don’t be surprised when they act like nothing more than an animal.
Children need to be taught they’re life is valuable. Children need to be taught they’re more than an animal. Children need to be taught they have a soul that distinguishes them from the animal world.
When these things are taught, then, and only then can we expect them to see other people in the same light.
Until then, children who continue to grow older (which is different from growing-up/maturing) in an amoral home, culture and society will do no more than what an animal naturally does…prey on the weak, take what can be taken, kill for the fun of it, and create offspring instead of a family.
But perhaps, at the end of the day, acting like an animal is the right and natural thing to do. Because after all, “survival of the fittest” is what got people to where we are right?
“Train up a child in the way he should go, and when he is old he will not depart from it.” (Proverbs 22:6)