DOI: 10.5061/dryad.1g1jwstxc
title: A shrewd inspection of vertebral regionalization in large shrews (Soricidae: Crocidurinae)

description: The regionalization of the mammalian spinal column is an important
 evolutionary, developmental, and functional hallmark of the clade.
 Vertebral column regions are usually defined using transitions in external
 bone morphology, such as the presence of transverse foraminae or rib
 facets, or measurements of vertebral shape. Yet the internal structure of
 vertebrae, specifically the trabecular (spongy) bone, plays an important
 role in vertebral function, and is subject to the same variety of
 selective, functional, and developmental influences as external bone
 morphology. Here we investigated regionalization of external and
 trabecular bone morphology in the vertebral column of a group of shrews
 (family Soricidae). The primary goals of this study were to: 1) determine
 if vertebral trabecular bone morphology is regionalized in large shrews,
 and if so, in what configuration relative to external morphology; 2)
 assess correlations between trabecular bone regionalization and functional
 or developmental influences; and 3) determine if external and trabecular
 bone regionalization patterns provide clues about the function of the
 highly modified spinal column of the hero shrew Scutisorex. Trabecular
 bone is regionalized along the soricid vertebral column, but the
 configuration of trabecular bone regions does not match that of the
 external vertebral morphology, and is less consistent across individuals
 and species. The cervical region has the most distinct and consistent
 trabecular bone morphology, with dense trabeculae indicative of the
 ability to withstand forces in a variety of directions. Scutisorex
 exhibits an additional external morphology region compared to unmodified
 shrews, but this region does not correspond to a change in trabecular
 architecture. Although trabecular bone architecture is regionalized along
 the soricid vertebral column, and this regionalization is potentially
 related to bone functional adaptation, there are likely aspects of
 vertebral functional regionalization that are not detectable using
 trabecular bone morphology. For example, the external morphology of the
 Scutisorex lumbar spine shows signs of an extra functional region that is
 not apparent in trabecular bone analyses. It is possible that body size
 and locomotor mode affect the degree to which function is manifest in
 trabecular bone, and broader study across mammalian size and ecology is
 warranted to understand the relationship between trabecular bone
 morphology and other measures of vertebral function such as intervertebral
 range of motion.
description: Scans of soricid vertebral columns (museum specimens sourced from
 the Field Museum of Natural History) were collected using a GE phoenix
 v|tome|x µCT scanner. Linear measurements were taken on 3D models of
 vertebrae using Meshmixer and 3DSlicer. Spherical VOIs were chosen and
 segmented in ORS Dragonfly 2020.1. Deep learning classifiers were trained
 using ORS Dragonfly's Deep Learning Toolkit. TBA data were collected
 from spherical VOIs using Quant3D. See publication Methods section for
 additional details.
description: Each data type (Deep Learning classifiers, spherical VOIs, linear
 and trabecular bone measurements) has a relevant ReadMe file with all
 relevant and necessary details.