I think what is meant here is the fact that the borders of African countries are unusually straight and do not follow natural landscapes (see the borders between Namibia and Botswana) - this is a legacy of how the land was shared by the colonial powers.
Body language because you can actaully tell from what they are doing and trying to do and what there next step will be.
Answer: avoid emmiting opinion about what was the main feeling being expressed in the act by the characters for being unsure in identifying what exactly would the facial expressions mean.
Explanation: According to these authors surveys - in which Masuda is one of them - oriental individuals, including the japanese, are more used to recognizing the situational motivation and overall mood when there is a more explicit balance of expressions on the characters. This social characteristic could be better understood if you can conceive their prioritization on group value, mood and will, in comparison to the importance of lone individual or inner self expression, more common in ocidental world culture. It is even stated that, in japanese culture, adapting your self expression to the group´s line is considered to be a sign of maturity and appropriateness in social conduct.
