Answer to Question 1
There is an arbitrary selection of traits used to define races, an inability to describe intra-species variation through racial categories, and repeated independent evolution of so-called racial traits in a population with no genetic relationship.
Answer to Question 2
While ethnocentrism is the belief that our own way of life is superior, cultural relativism helps us to understand the logic other cultures; it increases our understanding of others and is a fundamental anthropological research tool.
