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High-elevation late Pleistocene (MIS 6–5) vertebrate faunas from the Ziegler Reservoir fossil site, Snowmass Village, Colorado

Published online by Cambridge University Press:  20 January 2017

Joseph J.W. Sertich ,
Richard K. Stucky ,
H. Gregory McDonald ,
Cody Newton ,
Daniel C. Fisher ,
Eric Scott ,
John R. Demboski ,
Carol Lucking ,
Brianna K. McHorse  and
Edward B. Davis
Joseph J.W. Sertich*
Affiliation:
Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA
Richard K. Stucky
Affiliation:
Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA
H. Gregory McDonald
Affiliation:
Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA Museum Management Program, National Park Service, 1201 Oakridge Drive, Fort Collins, CO 80525, USA
Cody Newton
Affiliation:
Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA Department of Anthropology, University of Colorado — Boulder, Hale Science 350/233 UCB, Boulder, CO 80309-0233, USA
Daniel C. Fisher
Affiliation:
Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA University of Michigan Museum of Paleontology, 1109 Geddes Avenue, Ann Arbor, MI 48109, USA
Eric Scott
Affiliation:
San Bernardino County Museum, 2024 Orange Tree Lane, Redlands, CA 92374, USA
John R. Demboski
Affiliation:
Department of Zoology, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA
Carol Lucking
Affiliation:
Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA
Brianna K. McHorse
Affiliation:
Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
Edward B. Davis
Affiliation:
Department of Geological Sciences, University of Oregon Museum of Natural and Cultural History, 1680 East 15th Avenue, Eugene, OR 97403, USA
*
⁎Corresponding author at: Department of Earth Sciences, Denver Museum of Nature & Science, 2001 Colorado Boulevard, Denver, CO 80205, USA.E-mail address:jsertich@dmns.org (J.J.W. Sertich).
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Abstract

The vertebrate record at the Ziegler Reservoir fossil site (ZRFS) near Snowmass Village, Colorado ranges from ~140 to 77 ka, spanning all of Marine Oxygen Isotope Stage (MIS) 5. The site contains at least 52 taxa of macro- and microvertebrates, including one fish, three amphibian, four reptile, ten bird, and 34 mammal taxa. The most common vertebrate is Ambystoma tigrinum (tiger salamander), which is represented by >22,000 elements representing the entire life cycle. The mastodon, Mammut americanum, is the most common mammal, and is documented by >1800 skeletal elements making the ZRFS one of the largest accumulations of proboscidean remains in North America. Faunas at the ZRFS can be divided into two groups, a lake-margin group dating to ~140–100 ka that is dominated by woodland taxa, and a lake-center group dating to ~87–77 ka characterized by taxa favoring more open conditions. The change in faunal assemblages occurred between MIS 5c and 5a (vertebrates were absent from MIS 5b deposits), which were times of significant environmental change at the ZRFS. Furthermore, the ZRFS provides a well-dated occurrence of the extinct Bison latifrons, which has implications for the timing of the Rancholabrean Mammal Age in the region.

Keywords

Ziegler Reservoir fossil siteVertebrate faunasPleistoceneSnowmass VillageRancholabrean
Type
Articles
Information
Quaternary Research , Volume 82 , Issue 3 , November 2014 , pp. 504 - 517
Copyright
University of Washington

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