One of the more striking developments in modern North American dance was African American choreographer Katherine Dunham's introduction of a technique known as dance-isolation, in which one part of the body moves in one rhythm while other parts are kept stationary or are moved in different rhythms. The incorporation of this technique into North American and European choreography is relatively recent, although various forms of the technique have long been essential to traditional dances of certain African, Caribbean, and Pacific-island cultures. Dunham's success in bringing dance-isolation and other traditional techniques from those cultures into the mainstream of modern North American dance is due in no small part to her training in both anthropological research and choreography.
As an anthropologist in the 1930s, Dunham was one of the pioneers in the field of dance ethnology. Previously, dance had been neglected as an area of social research, primarily because most social scientists gravitated toward areas likely to be recognized by their
Starting in 1935, Dunham conducted a series of research projects into traditional Caribbean dance forms, with special interest in their origins in African culture. Especially critical to her success was her approach to research, which diverged radically from the methodology that prevailed at the time.
Between 1937 and 1945, Dunham developed a research-to-performance method that she used to adapt Caribbean dance forms for use in theatrical performance, combining them with modern dance styles she learned in Chicago. The ballets she created in this fashion were among the first North American dances to rectify the exclusion of African American themes from the medium of modern dance. Her work was thus crucial in establishing African American dance as an art form in its own right, making possible future companies such as Arthur Mitchell's Dance Theater of Harlem.
According to the passage, which one of the following was true of the dance forms that Dunham began studying in 1935?
They were more similar to dance forms used in Pacific-island cultures than to any other known dance forms.
They represented the first use of the technique of dance-isolation within a culture outside of Africa.
They shared certain rhythmic characteristics with the dance forms employed in North American ballets.
They had already influenced certain popular dances in North America.
They were influenced by the traditions of non-Caribbean cultures.