DOI: 10.5061/dryad.gqnk98srz
title: Forelimb morphology as an adaptation for burrowing in kangaroo rat species (genus Dipodomys) that inhabit different soil substrates

description: Among burrowing rodents, forelimb morphology frequently shares an
 intricate relationship with soil substrates. Soils can vary widely in
 texture and density, leading to differences in friability, which often
 requires forelimb specializations in digging animals. Kangaroo rat species
 (genus Dipodomys) dig and occupy underground burrows, a trait which is
 essential to their survival. Some members of this genus are restricted to
 particular types of soil substrates that presumably require
 species-specific forelimb traits. Here we explored the forelimb morphology
 and soil substrates inhabited by four Dipodomys species, including two
 range-restricted species (D. compactus and D. elator) and two
 widely-ranging species (D. merriami and D. ordii) in an effort to explore
 the variation in soil usage, forelimb skeletal specializations, and the
 relationship between these traits. We assessed the size and shape traits
 of preserved specimen forelimb bones using traditional and geometric
 morphometric techniques and we extracted soil data associated with the
 collecting locality of each specimen. We expected the four species to
 differ in their substrate affinities and forelimb morphology.
 Specifically, we expected species that inhabit dense soil substrates
 (e.g., clay-rich soils) to display specialized forelimb morphology
 typified by an elongated scapula and robust humerus, radius, and ulna
 bones. The four Dipodomys species differed substantially in their soil
 associations. We also detected significant morphological differences among
 Dipodomys species in which forelimb traits allowing for greater mechanical
 digging ability were found in D. elator, a species that inhabits dense
 clay-rich soils. These findings suggest that Dipodomys species that
 inhabit dense substrates may require correspondingly specialized forelimb
 morphology and that these traits may limit the desirable geographic ranges
 inhabited by these species. This may provide particularly important
 information when making conservation decisions on behalf of these species
 given that, unlike other habitat features, soil substrates cannot be
 easily modified to suit the needs of the organism.
description: # Forelimb morphology and soil substrates inhabited by kangaroo rat
 species
 [https://doi.org/10.5061/dryad.gqnk98srz](https://doi.org/10.5061/dryad.gqnk98srz) This readme file was generated on [2022-10-04] by [Leila Siciliano-Martina] GENERAL INFORMATION Title of Manuscript: Forelimb morphology as an adaptation for burrowing in kangaroo rat species (Genus Dipodomys) that inhabit different soil substrates Authors: Leila Siciliano-Martina, Daniel A. Guerra, Joseph A. Veech Corresponding Author Name: Leila Siciliano-Martina ORCID: 0000-0002-0004-5407 Institution: Texas State University, San Marcos, Texas Email: sicilia.marti@gmail.com This README file describes the data accompanying the above publication. Files: 1\. krat\_morpho\.xlsx: This file includes the full list of museum specimens used for the morphological analyses including the major specimen attributes \(provided by the museum\) and the raw morphological measures\. * Museum institution codes include ASNHC (Angelo State Natural History Collection, Angelo State University, San Angelo, TX), MSB (Museum of Southwestern Biology, University of New Mexico, Albuquerque, NM), TCWC (Biodiversity Research and Teaching Collections, Texas A&M University, College Station, TX), TTU (Natural Sciences Research Laboratory, Texas Tech University, Lubbock, TX). * Specimen data includes the museum catalog number, the trapping locality (country, state, and county), the specimen sex, and the genus and species names. * Specimen sexes include F (female), M (male), and U (unknown sex). * The morphological data includes Principal Component 1 (PC1) and Principal Component 2 (PC2) and the centroid size of the ulna, humerus, and scapula, as well as the raw linear measures in millimeters. * The raw measures include ulna length (UL), ulna width (UW), length of olecranon process (UOP), radius length (RL), radius width (RW), scapula length (SL), scapula width (SW), humerus length from the deltoid crest to the humeral head (HdCL), humeral tuberosity width (HtW), total humerus length (HL), total humerus width (HW), humerus width at the epicondyles (HbW), and the linear indices including length of olecranon process relative to the ulna length (UOP\_UL), ulna width relative to ulna length (UW\_UL), ulna length relative to radius length (UL\_RL), scapular width relative to scapular length (SW\_SL), humerus length from the deltoid crest to the humeral head relative to total humerus length (HdCL\_HL), humerus width at the epicondyles relative to (HbW\_HL), humeral tuberosity width relative to humeral length (HtW\_HL), humerus width relative to humerus length (HW\_HL), olecranon process length relative to radius length (UOP\_RL), radius width relative to radius length (RW\_RL), and humerus length relative to radius length (HL\_RL). Any missing morphological data is indicated by NA. 2\. Soil data k\-rat buffers\.xlsx: This file includes all of the kangaroo rat locality observations along with the percentage of each locality that is composed of the eight soil types for the 25m\, 50m\, and 75m buffers around each kangaroo rat locality\. Each soil buffer is also divided into three soil depths\, a top layer \(the soil type at the surface\)\, a middle layer \(the soil at a depth of 25cm\)\, and the bottom layer \(the soil at a depth of 25\.1\-100cm\)\.