DOI: 10.5061/dryad.nk98sf825
title: Data from: Wolf cranial morphology tracks population replacement in Fennoscandia

description: Humans have directly or indirectly contributed to the genetic, and thus
 often phenotypic, changes of many species. Anthropogenic pressures, such
 as persecution and hunting, have negatively affected wolf populations in
 Northern Europe. In line with the genetic replacement that occurred during
 the 20th century following the extirpation of wolves from Scandinavia
 (Norway and Sweden) and their near-extirpation from Finland, we provide
 evidence of morphological changes in wolf cranial morphology across these
 populations. Using 3D landmark-based geometric morphometrics, we show that
 modern wolves in Scandinavia and Finland have, on average, crania with
 wider frontal bones, wider and higher positioned zygomatic arches, and
 more ventral flexion of the rostrum compared to the historical wolf
 populations. Although both populations differ in the magnitude and
 direction of shape change over time, the centroid size, or overall size of
 the cranium, is significantly larger only in the modern Scandinavian
 wolves. Different genetic origins of the historical and modern populations
 have likely played a role in the observed morphological variation;
 however, it is also likely that morphology has been affected by the
 availability of different prey, which has changed over time.
description: Data was collected from CT-scanned wolf skull specimens and then
 landmarked in Stratovan Checkpoint v.2023 (Stratovan Corporation,
 Sacramento, USA).
description: # Wolf cranial morphology tracks population replacement in Fennoscandia -
 dataset \[Access this dataset on
 Dryad: [https://doi.org/10.5061/dryad.nk98sf825](https://doi.org/10.5061/dryad.nk98sf825)] This dataset contains all 84 landmark files in .nts format used in the article "Wolf cranial morphology tracks population replacement in Fennoscandia" as well as the specimen information in "wolf_info.csv" necessary for the analyses. We also provide R script compiled for the article and additional .csv files (wolf_curves.csv and wolf_links_surface.csv) used for the analyses. ## Descriptions ### wolf\_info.csv Contains all necessary information for the samples and for the analyses. Column descriptions: **ID** - denotes the .nts file IDs **groups_9** - dataset divided into 9 groups for highlighting groups with small sample sizes: * "Fennoscandia_NAN" * "Fennoscandia_Russia_north" * "Fennoscandia_Russia_south" * "Fennoscandia_zoo" * "Finland_after" * "Finland_before" * "Finland_maneater" * "Scandinavia_after" * "Scandinavia_before" **groups_6** - dataset divided into 6 groups for analyses and graphs: * "Fennoscandia_NAN" * "Fennoscandia_zoo" * "Finland_after" * "Finland_before" * "Scandinavia_after" * "Scandinavia_before" **region** - 3 groups, this is relevant when subsetting the data and for graphs. * "Finland" * "Scandinavia" * "Fennoscandia" (those samples with unknown year and from the zoo) **temporal_group** - 4 groups, this is relevant for trajectory analysis: * "historical" * "modern" * "unknown" * "zoo" **year** - relevant when plotting, samples with unknown year or zoo samples are set to 2040 for plotting **yeargroup** - whether the samples should be included in the "year" dataset: "no" "yes" **sexgroup** - groupings for sexual dimorphism analyses in Scandinavia: * "before_m" - males before the replacement  * "before_f" - females before the replacement  * "before_NAN" - unknown sex before the replacement  * "after_m" - males after the replacement  * "after_f" - females after the replacement  * "after_NAN" - unknown sex after the replacement  * "NAN_NAN" - unknown year of collection, unknown sex * "Russia_south_m" - sample from southern Russia, male * "Russia_south_NAN" - sample from southern Russia, unknown sex * "Russia_north_NAN" - sample from northern Russia, unknown sex * "zoo_NAN" - old zoo samples without collection information on sex * "zoo_f" - zoo samples, female **year_original** - original collection dates, "empty cell" denote no year in the museum collection was recorded **Museum_ID** - original museum ID **State** - state based on museum records **Location** - location based on museum records, "empty cell" denotes no collection location was recorded **Stage_year** - developmental stage or age as available in museum records * "ad" - adult * "number" - denotes estimated age in years * "NA" - unknown age/stage, not recorded in the museum records **sex** - females or males as stated in museum records * "m" - males * "f" - females * "NA" - unknown sex **zoo** - whether the specimen was from the zoo * "zoo" - specimen is from the zoo * "empty cell" - specimen is from the wild **Museum** - museum where the samples are stored ### wolf\_curves.csv This file denotes which landmarks are part of the curves = semi-landmarks, which is necessary for gpagen = generalized procrustes analysis. ### wolf\_links\_surface.csv This file denotes links between the landmarks, which is necessary for the figure - wireframe graphs. ### land\_pairs.csv The file contains paired landmark numbers corresponding to points on each side of the skull. These pairs are required for the *bilat.symmetry* function in the *geomorph* package in R, which extracts the bilaterally symmetric component of shape used in subsequent analyses. ### Mean\_250.ply This 3D file represent a mean shape of the whole configuration and is used for graphical interpretation of shape change along principal component axes in R.  ### nts files for 84 specimen nts files contain landmark data that is used for the analyses. The file names correspond to the wolf_info.csv column "ID". Each file contains landmark data for one specimen, the header denotes number of landmarks, dimensions, and if there is any missing data. Missing data is denoted with "9999". ### Landmarking\_data\_84\_specimens.tps This file contains the raw three-dimensional coordinate data for 84 specimens. The file contains the number of landmarks, 3D coordinates, and specimen IDs. Missing data is denoted as "NA". The name of each specimen contains the specimen number as per museum, and the museum location. Table with necessary information for each sample is supplied as a supplementary data of the article. ### Fennoscandia\_Patches\_Final\_code.R = R-script R code contains information for all analyses, including the required packages and code annotations. Once the dataset is downloaded from DRYAD, there is no need to change the directory as the code is set up to run directly from the downloaded folder. The script was created in R v4.3.3. ## Software Files were obtained by landmarking the 3D specimens in Stratovan Checkpoint and analyzed using R scripts (1). The main package for analyses was geomorph (2,3). All information on the workflow and analyses is stated within the methods section of the article. ## References 1. R Core Team. R: A Language and Environment for Statistical Computing. Vienna, Austria; 2024. Available from: [https://www.R-project.org/](https://www.R-project.org/) 2. Adams D, Collyer M, Kaliontzopoulou A, Baken E. Geomorph: Software for geometric morphometric analyses. R package version 4.0.7. 2024. Available from: [https://cran.r-project.org/package=geomorph](https://cran.r-project.org/package=geomorph) 3. Baken EK, Collyer ML, Kaliontzopoulou A, Adams DC. geomorph v4.0 and gmShiny: Enhanced analytics and a new graphical interface for a comprehensive morphometric experience. Methods Ecol Evol. 2021 Dec 1;12(12):2355–63.