Chaney was the first paleobotanist to develop in detail the use of morphological characters of fossil leaves to deduce ecological information of the given era.

After his graduation, Chaney briefly moved to South Dakota before enrolling at the University of Chicago in the fall of 1908.

Chaney began to work towards a graduate degree in paleontology at the University of Chicago, studying under Stuart Weller.

[2] Following an invitation from John Campbell Merriam, Chaney took a position at the University of California, Berkeley while still continuing to do research for the Carnegie Institution.

He spent 1933 at the cave site of Zhoukoudian in the search for specimens of the "Peking Man" under the direction of Davidson Black.

[2] In 1939, he served as president of the Paleontological Society of America[1] Following the breakout of World War II, Chaney contributed to the establishment of the Campus Catastrophe Relief Organization, a precursor to the Civil Defence Corps.

He also volunteered as an aid in the Selective Service System by serving as Chairman of the University Area Draft Board.

In 1944, Chaney was appointed as assistant director of the Radiation Laboratory, which was undergoing research for the Manhattan Project.