Identifying and siding the stylohyoid bone for North American artiodactyls

Abstract

The stylohyoid is the largest bone in the hyoid complex surrounding the throat in artiodactyls. There is little published information to allow its identification to species or anatomical side. Our study examined comparative stylohyoid bones to provide criteria for taxonomic identification, using 494 animals representing 13 artiodactyl species, including all species native to the continental United States. The goal was to find criteria showing at least 95% success in separating between species or species groups. Osteometric and discrete feature criteria were found to provide strong distinctions between some species through an iterative set of comparisons arranged in a dichotomous key. For example, a small artiodactyl bone could be identified as pronghorn (Antilocapra americana) with 100% success (n = 260) if it exhibited both an S‐shaped dorsal aspect and a ratio of angle width to anterior end width > 1.6. Consistent criteria could not be found for some other species, notably between small bovids and between the 2 species of deer (Odocoileus sp.). Our study also extracted stylohyoids in place to provide criteria for siding, using 28 carcasses representing 7 species, and found they can be readily sided based on a marked concavity on the lateral side.

Blind Testing of Faunal Identification Protocols: A Case Study with North American Artiodactyl Stylohyoids

“…We implemented a test of the protocol proposed by Lubinski and Hale (2018) for identifying stylohyoids of North American artiodactyls, hereafter referred to as the LH protocol. This protocol provides an ideal test case.…”

“…The artiodactyl stylohyoid (1) is large enough for consistent archaeological recovery (measuring 4–19 cm in length for adult specimens); (2) is commonly found at North American archaeological sites (up to half as common as the most abundant skeletal element at some sites); (3) often exhibits evidence of butchery and is sometimes manufactured into pendants; and (4) is not well known by many zooarchaeologists (no North American artiodactyl skeletal key includes this element), so documenting it will contribute to zooarchaeological knowledge (Lubinski and Hale 2018). The stylohyoid is the largest bony element in the hyoid complex of artiodactyls in the Antilocapridae, Bovidae, and Cervidae.…”

“…Lubinski and Hale (2018) recorded metric and morphological traits of nearly 500 reference hyoids of 13 species (10 genera, three families) of North American artiodactyls. They determined which traits seemed to distinguish taxa and estimated the rate of accurate identifications using the traits.…”

“…To test the validity, reliability, and usability of the LH protocol, we obtained stylohyoids of known taxonomy from four zooarchaeology reference collections: California State University, Chico (CSUC); Eastern Tennessee State University (ETSU); Iowa State University (ISU); and Indiana University (IU). None of these test specimens had been used by Lubinski and Hale (2018) to develop this protocol. Lubinski received collection loans and removed specimens with significant breakage or adhering connective tissue that would complicate measurement, yielding a test sample of 77 stylohyoids representing 11 species of North American artiodactyls (Table 1).…”

“…Zooarchaeologists have spent countless hours scrutinizing skeletons of known taxonomic identity to determine which skeletal traits are taxonomically diagnostic and which ones are not. In North American zooarchaeology, this process began in the late nineteenth century (Eaton 1898) and has extended continuously up to the present (e.g., Adams and Crabtree 2012; Balkwill and Cumbaa 1992; Brainerd 1939; Brown and Gustafson 1979; Gilbert 1973; Jacobson 2003; Lawrence 1951; Lubinski and Hale 2018; Olsen 1964).…”