Land forms can affect people by elevation, like a plateau, it's elevated an means colder, which means less species, which means humans lving there adapt, something like that.
Moral altruism
they helped informed only by ethical consideration regardless of any rivalry between the teams. Moral altruism is the highest calling in altruism(helping others selflessly) the team did not consider that if they failed to provide shelter to the other team it would get some advantage over it.
Central America has a tropical humid climate.
Depends on the context. If you told more then I could help.
