Final answer:
Franz Boas's anthropological work in the early 20th century rebutted the race theory by showing that environmental factors, not genetics, influenced changes in skull forms among children of European immigrants in North America. His contributions highlighted the role of the environment on human development and advanced the view of cultural relativism in anthropology.
Step-by-step explanation:
In the early 20th century, anthropologist Franz Boas conducted studies that demonstrated significant changes in the skull forms among the children of European migrants in North America, changes that were not attributable to genetics. Boas's findings were instrumental in challenging the race theory of the time, which assumed racial and ethnic categories determined physical and behavioral traits. Instead, Boas's research suggested that environmental factors such as diet and medical care played a crucial role in shaping human biological characteristics. This emphasized the flexibility within human biology across generations and countered the prevailing racist theories in social science that supported a notion of white supremacy. Throughout his career, Boas contributed significantly to the field of anthropology. He rejected the ethnocentric view that cultures evolve along a single, unilineal trajectory toward' civilization.' His work showed that cultures develop their unique historical paths and constantly interact and exchange ideas, debunking the theories of cultural evolution in isolation. Boas's methodologies underlined the impact of social and environmental factors on human health and physiology and promoted cultural relativism over the ethnocentric and racist methodologies of his contemporaries. Franz Boas is also recognized for setting high standards of field research that laid the foundation for modern anthropological approaches. His emphasis on the need for anthropologists to gather ethnographic data directly from the cultures under study established him as a vanguard in academic anthropology.