हिमालयीय सीमावर्ती क्षेत्रों एवं पूर्वोत्तर भारत में मुख्य रूप से किस प्रजाति (Racial Group) के लोग निवास करते हैं?

In traditional anthropological classification of human races, which racial group was characterized as 'yellow-skinned'?

What is the approximate estimated proportion of ecumene (habitable) and non-ecumene (uninhabitable/sparsely inhabited) areas on the Earth's surface?