Tax intermittently served as Chair of the Department of Anthropology along with Robert Redfield after the retirement of Fay-Cooper Cole in the late 1940s.

Cole had built up the Archaeology Laboratory Skeletal Collection, which began during the earliest iterations of the department in the late 1890s through the 1940s.

The collection of human remains of both Indigenous and non-Indigenous people, bone fragments, and artifacts were compiled, studied, stored, and possibly exhibited on the campus.

The skeletal collection contained human remains and archaeological objects taken and collected by faculty, students, curators, and donors through excavations of Illinois burial mounds such as the Fisher Mounds, Starved Rock, Kincaid, Algeria, Globe, Arizona, among materials from private donors.

Skeletal remains of 400 Indigenous people, as well as 10,000 bone fragments, stone, pottery and shell implements and artifacts largely excavated from Fisher and Adler Mounds, were donated in 1930 by George Langford, an engineer from Joliet who as also an amateur anthropologist, an honorary Research Associate in the Department of Anthropology at the University of Chicago, and later Curator of Plant Fossils at Field Museum.

Under NAGPRA guidelines, these institutions are now responsible for deaccessioning and repatriating Native American human remains and funerary objects.

[6] The remaining skeletal materials do not account for extent of the historical collection; the department's report recommended that the majority be "dumped.

NAES credited Tax with playing a "key role in helping define a vision of Indian higher education as the basis for community development in culturally relevant terms."