Because there's actually more genetic difference between a black Kenyan and a black Ugandan than there is between a black Kenyan and, say, a white Norwegian.
Over a lifetime of stressful experiences, this one biological change could be the difference between a stress-induced heart attack at age 50 and living well into your 90s.
だって 遺伝的な違いで言えば 黒人であるケニア人と ウガンダ人を比べる方が 黒人であるケニア人と 白人のノルウェー人よりも大きいのよ 