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Title: Stable isotope analysis of deer remains from Alameda County show the effects of the Medieval Climatic Anomaly
To date, there have been no large-scale investigations of mule deer (Odocoileus hemionus) from a single site using stable isotopes, but CA-ALA-554 provides the perfect opportunity for such research. CA-ALA-554 is an ancestral Ohlone site in modern-day Pleasanton that yielded abundant deer remains across 83 burials. AMS radiocarbon dates indicate that people lived here and deposited the deer bones between 400 and 2,000 calibrated years before present. Our goal is to document shifts in deer ecology, especially diet and migratory behaviors, across this swath of time using isotopic signals. Analysis of carbon and nitrogen isotopes reveal overall similarity in diet across the sampled population, with slight variation between individuals. Notably, an increase in variation for both δ13C and δ15N is observed between 800 and 1,000 cal BP, indicating that deer were either diversifying their diet locally or coming to CA-ALA-554 from a greater variety of places during this time than they were either before or after. We argue that the increased variation reflects the ecological stress faced by both mule deer and people during the Medieval Climatic Anomaly (650-1,220 cal BP), which forced one or both to alter their respective foraging and hunting practices.  more » « less
Award ID(s):
2021256
PAR ID:
10546370
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Proceedings of the Society for California Archaeology
Date Published:
Volume:
36
Page Range / eLocation ID:
13-22
Format(s):
Medium: X
Location:
https://drive.google.com/file/d/1RqgHmbGu8UO-APtyQxilWCCznPwIlsl_/view?usp=sharing
Sponsoring Org:
National Science Foundation
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