It seems fitting that William John Sinclair (b. 1877, d. 1935) was born in the same year that William Berryman Scott,
Henry Fairfield Osborn and Francis Speir set out on the first Princeton
Scientific Expedition, for his contribution to Princeton University’s
vertebrate paleontology program is no less significant.
A student of John C. Merriam at the University of California at
Berkeley, Sinclair received both his M.S. and Ph.D. degrees in 1904.
That same year he came to Princeton as a Fellow. His subsequent
appointments included Instructor in Geology in 1905, Assistant
Professor in 1916, Associate Professor in 1923, and Professor in 1930.
Before coming to Princeton, he had authored several papers on a variety
of subjects, including: descriptions of Protapirus robustus, a fossil tapir, and Mylagaulodon angulatus,
a fossil rodent, both from Oregon; reports on the exploration of Potter
Creek Cave in California; and the description of a new species of Stylemys from the Sierra Nevada of California.
In the hiatus between the loss of John Bell Hatcher
to Pittsburgh and the arrival of Sinclair, Princeton’s vertebrate
paleontology field collecting program continued with M.S. Farr, ably
assisted by Al Silberling, leading small groups of students to Montana.
Sinclair began leading expeditions in 1911 and continued to do so for
several years. The focus of his collecting centered on 3 areas: the
Bighorn Basin of Wyoming, the White River Badlands of South Dakota, and
the Miocene and Pliocene beds of the Snake Creek region of Nebraska. He
also continued to work on the mammalian cave faunas of California and
the fossil faunas of the John Day River Basin of Oregon.
His 1906 paper, “Volcanic Ash in the Bridger Basin of Wyoming,” was the
first to use microscopic studies to reveal the presence of volcanic ash
in the sediments of the Bridger Basin. That Sinclair emphasized the
interdependence of stratigraphy and paleontology can be seen in the
detailed stratigraphic information that accompanied many of his
taxonomic descriptions. He authored the marsupial and typothere
portions of the Reports of the Princeton University Expedition to Patagonia, and with M.S. Farr co-authored the report on birds.
According to Glenn L. Jepsen,
Sinclair’s student and successor, Scott spent most of his time on his
own research, leaving the museum’s development and the training of
graduate students in Sinclair’s capable hands. It was Sinclair who
instituted and secured funding for Princeton’s William Berryman Scott
Fund for research in vertebrate paleontology. He willed his own estate
to the university to establish the Sinclair Professorship of Vertebrate
Paleontology so that Princeton’s tradition of research and teaching in
that discipline would continue.