Tan continued his study in the United States and received PhD from the California Institute of Technology in 1937, under the supervision of Theodosius Dobzhansky.
After Tan returned to China, he became a professor at the Department of Biology of Zhejiang University in Hangzhou.
"As part of the Morgan group in the 1930s, Tan helped make Drosophila pseudoobscura the leading species for evolutionary studies and did pioneering work in insect genetics.
In spite of interruptions by Lysenkoism and by the Cultural Revolution, Tan was still scientifically active in China."
Tan died on 1 November 2008 of multiple organ dysfunction syndrome at the age of 99 in Shanghai.