evolutionary pressure affects individual and group differently

a panther hunts alone 

there is a lot of evolutionary pressure on that individual 

lions hunt together 

there is less evolutionary pressure on individual 

but there is more evolutionary pressure on group 

many gazelle flee together 

there is very little evolutionary pressure on individual 

but there is very much evolutionary pressure on group 

very many chickens live together in farm which is an artificial environment 

there is extremely little evolutionary pressure on individual 

but there is extremely much evolutionary pressure on group 

if chickens start picking on each other then that could lead to injuries which could lead to diseases that kill almost all chickens in group 

very many humans live together in cities which is an artificial environment 

there is extremely little evolutionary pressure on individual 

but there is extremely much evolutionary pressure on group 

if humans abuse each then that could lead to conflicts 

which could lead to societal collapse that kill almost all humans in group 

these factors have lead to that the human brain evolved to have free will 

which made humans adept to improvise in seemingly complex situations 

and it indicates that species that live in very large groups have low tolerance against abuse within the group 

and could have evolved their own instinctive group strategies to handle abusive individuals 

it's even possible that abusive individuals become too abusive so that they are more easily detected and handled by the group 

so that abusive individual do a form of evolutionary suicide to enable the species to survive