Affiliation:
1. School of Biological Sciences Georgia Institute of Technology Atlanta Georgia USA
2. Department of Anatomy and Cell Biology Oklahoma State University Center for Health Sciences Tulsa Oklahoma USA
3. Department of Cellular and Molecular Medicine University of Arizona Health Sciences Tucson Arizona USA
Abstract
AbstractCranial bony projections (“headgear”) have diverse forms and functions, such as defense, species recognition, mate selection, and thermoregulation. Most commonly, they are associated with the artiodactyl infraorder, Pecora. All pecoran headgear—antlers, horns, ossicones, and pronghorns—are osseous protrusions of the frontal or parietal bone with an integumentary covering, although there is taxonomic, developmental, and compositional variation. However, compared with other pecorans, there is a dearth of literature addressing extant antilocaprids—Antilocapra americana. This study provides a foundational osteohistological description of A. americana pronghorn cores in order to start building a framework to better understand the complex interplay among microanatomy, development, behavior, environment, and phylogenetic history of pronghorn headgear. Osteohistological analysis of adult A. americana pronghorn cores reveal the inner medullary region is composed of trabecular bone. Based on similar studies in bovids, we propose that these trabeculae may function to reduce the effects of repeated loading incurred by intraspecific combat. The deep aspect of the outer region was found to be composed of compacted coarse cancellous bone and primary bone remodeled to dense Haversian bone, in both male and female specimens, respectively, and superficially composed of highly vascularized fibrolamellar bone. The presence of fibrolamellar bone may indicate that the bone is fast‐growing, and its presence at the periosteal surface suggests protracted growth of the pronghorn core beyond sexual maturity.
Funder
Center for Health Sciences, Oklahoma State University
Subject
Ecology, Evolution, Behavior and Systematics,Histology,Biotechnology,Anatomy