MicroCT Imaging of Red fox Talus: A Non‐Invasive Approach to Evaluate Age at Death

Abstract

X-ray microCT imaging offers the possibility to study age-related changes of bone microstructure. In the present paper we analyse the talus of 15 modern red foxes of different ages, from 2 months old to adulthood, to investigate the possibility of identifying their different ages at death. Surface and volumetric variables describing bone properties are measured or evaluated from the microCT images following three approaches: (i) the bone volume to total volume ratio, quantified for the whole bones; (ii) two homologous subvolumes of trabecular tissue, virtually extracted and analysed to evaluate trabecular bone structure; and (iii) the development of the cortical region, deduced through the analysis of bone cross-sections. All approaches yielded interesting information on bone development, and preliminary results show that the third approach clearly allows us to discriminate among different age groups. This is important both from a zooarchaeological and a palaeontological perspective, suggesting that microCT imaging can be considered a new non-invasive tool to estimate the age at death of animal remains, or to discriminate taxa characterized by a close morphology but different adult body size.

A Non-Destructive Method for Distinguishing Reindeer Antler (Rangifer tarandus) from Red Deer Antler (Cervus elaphus) Using X-Ray Micro-Tomography Coupled with SVM Classifiers

“…We have shown that the structural characteristics of antler are reliable in identifying samples with a useful degree of phylogenetic precision—these two species are separated only by subfamily: Cervinae for red deer and Capreolinae for reindeer [ 68 ]. More generally, although the expression of the phenotype could be influenced by multiple endogenous (sex, age, and heredity) and exogenous (nutrition, photoperiod, accidents during development, and social relations) factors specific to each individual [ 69 – 75 ], the morphometric criteria identified in this study nonetheless appear to be promising biomarkers.…”

A Look from the Inside: MicroCT Analysis of Burned Bones

“…The choice of these specimens was influenced by their availability. The fox bones (specimens 1 and 2) were analyzed in a previous study (Boschin et al 2015) and are part of the osteological reference collection of the University of Siena (specimens 160 and 149, respectively). The red fox and roe deer specimens came from adult individuals, while the domestic pig talus came from a subadult (about 1 year old).…”

“…First, since trabecular structure is related to an animal's form of locomotion (Barak et al 2001), biomechanical studies involving burned bones need to consider how burning may contribute to the observed trabecular structure. Trabecular parameters are also related to age-at-death (Boschin et al 2015) and heat-induced changes could lead to misinterpretations if the age-at-death is inferred from microscopic observations. The analysis of burned specimens belonging to different age classes would help to clarify if burned specimens can be analysed to obtain at least an approximate age-at-death.…”

“…High resolution X-ray imaging is increasingly used in zooarchaeological research to better understand taphonomic processes that bones undergo during butchery and deposition in the archaeological record (Bello et al 2013;Boschin et al 2015;Bradfield 2013;Shackleford et al 2013;Tuniz et al 2012). This approach is relatively new in archaeology and offers the opportunity to develop and improve analytical protocols for zooarchaeological research into bone microstructure.…”

“…This approach is relatively new in archaeology and offers the opportunity to develop and improve analytical protocols for zooarchaeological research into bone microstructure. Since the physical properties of mammal bone are related to age and adaptation to mechanical loads, characteristics of bone microstructure can be indicative of age-at-death and life history conditions (Agarwal et al 2004;Barak et al 2011;Boschin et al 2015;Brickley et al 1999;Macho et al 2005;Tanck et al 2001;Shackleford et al 2013). For instance, bone microstructure has the potential to yield inferences about domestic stock management or to differentiate domestic individuals from their wild ancestors (Boschin et al 2015;Shackleford et al 2013).…”