Centennial Paleontology Site - Discovery

Routine Investigation Reveals Fossils
In July 2003, paleontologists were on a routine investigation of fossil sites in the park when something caught their attention. It was a very large set of fossil teeth. Careful study revealed that these were the teeth of an ancient hornless rhinoceros - Subhyrocodon occidentalis.
Dr. Greg McDonald discusses this discovery - Real Media File 2.4 mb

Protecting the Fossils

From the time of the first discovery in July, until Dr. Greg McDonald could return to do a full investigation several weeks later, wind, rain, and drying conditions caused the fossils to deteriorate.


The formation in which these fossils lie is the White River Group. These claystones have been affected by the changing climates since the time they were uncovered by the erosional effects of wind and rain and of freezing and thawing.

As the clay became wet and dry, it expanded and contracted causing the fossils to become extremely fractured and fragile.

For more information about the Centennial Site click on the links below.

Site Map
Rhinoceros Skeleton
Rhinoceros Skull
Mesohippus Skeleton
Excavating the Site in 2003
Excavating the Site in 2004
Jacketing Fossils
Jacketing Large Fossils
Moving the Jacketed Fossils
Centennial Paleontology Site Overview

Read the press release about the discovery.

Last updated: February 14, 2019

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