Kenneth P. Cannon
ABSTRACT
In 2003 a partial bison skull was recovered by Ashley National
Forest archeologist Brian Storm from an elevation of 3840 m (12,600
ft) AMSL in the Uinta Mountains. The partial skull consists of
a portion of the frontal, occipital region, and horn cores including
horn sheaths. The presence of the horn sheaths is of particular
interest for the ecological information they can provide. Through
the analysis of the individual cones of the horn sheath a record
of the animal’s dietary and migration patterns can be obtained.
The skull was recovered downslope of Gilbert Peak in an alpine
environment. Tundra vegetation characterizes the area. Downslope,
and to the east, of the skull find is the headwaters area of
the Uinta River. This boggy area is drained by Gilbert Creek
with wet meadow vegetation and Engelmann spruce along the edge.
While high altitude bison remains have been discussed in the
scientific literature periodically over the past 80 years they
have not gone beyond the descriptive. The study of this specimen
focuses on a more complete understanding of bison ecology in
the intermountain west. In addition to metric analysis of the
skull, radiometric assay, and stable isotope analyses were applied.
The radiocarbon age of the specimen is 150 ± 40 yrs BP.
The 2 sigma calibrated age is cal AD 1660 to 1950. Metric analysis
of the skull indicates it was an adult male, at least 10 years
of age, that compares well with Bison bison athabascae in size
and is larger than either Bison bison bison specimens or other
high altitude bison. However, it is probable this individual
represents a member of the species Bison bison bison, but phenotypic
characteristics (e.g., large horn size) may be the result of
gene flow. More definitive taxonomic placement of the Gilbert
Peak bison may not be resolved without genetic analysis Temporal
and spatial gaps in the Holocenerecord of bison still exist and
isolated skulls can help fill them. Detailed analyses of these
specimens can provide an understanding of the history, the paleoecology,
and evolution of the species. The results of this study begin
to fill this gap.