Article Figures & Data
Figures
- Figure 1.
Neuroanatomical variation in domestic dogs. A, MRI images and 3D reconstructions of warped template from 10 selected dogs of different breeds. Images are public-domain photos from Wikimedia Commons. B, Unbiased group-average template for this dataset. See Figure 1-1, and Figure 1-2 for processing schematics. Neuroanatomical labels (based on Palazzi, 2011; Datta et al., 2012, Evans and de Lahunta, 2013) are as follows: (a) olfactory peduncle; (b) orbital (presylvian) gyrus; (c) proreal gyrus; (d) pre cruciate gyrus; (e) postcruciate gyrus; (f) marginal (lateral) gyrus; (g) ectomarginal gyrus; (h) suprasylvian gyrus; (i) ectosylvian gyrus; (j) sylvian gyrus; (k) insular cortex; and (l) piriform lobe. C, Brain-wide morphological variation, regardless of breed, as indexed by the SD of all dogs' Jacobian determinant images. D, A Monte Carlo permutation test on demeaned gray matter Jacobian determinant images revealed that much of gray matter shows significant deviation from group-mean morphology. Colored regions are all p < 0.05 after multiple-comparisons correction; t-statistic values are illustrated.
- Figure 2.
pGLS analyses on gross brain, body, and skull measurements. A, Brain volume versus body mass. B, Neurocephalic index vesus cephalic index. Plotted points represent breed averages, not individuals.
- Figure 3.
Covarying regional networks in dog brain morphology. Independent components analysis revealed six regional networks where morphology covaried significantly across individuals. Red and blue regions are volumetrically anticorrelated: in individuals where red is larger, blue tends to be smaller, and vice versa. Graphs represent volumetric quantification of the top five anatomical constituents of each of the two portions of each component.
- Figure 4.
Relationship between morphologically covarying regional brain networks and phylogenetic tree. Circles indicate factor loading. (Phylogenetic tree is from Parker et al., 2017.)
- Figure 5.
Relationship between morphologically covarying regional brain networks and ostensible behavioral specializations. Colors indicate partial correlation coefficients resulting from multiple regression analysis on source-based morphometry results. Outlined boxes are significant at p < 0.05.
Tables
ID Breed Sex Age (years) Body mass (kg) Cephalic index (from database) Neuro-cephalic index Brain volume (mm3) Ostensible behavioral specialization/purpose 1 Basset hound Male 4.0 28.1 0.74 51.89 100070.10 Scent hunting 2 Beagle Male 14.3 17.0 0.74 61.82 82750.29 Scent hunting 3 Beagle Male 4.0 11.7 0.76 61.82 64887.65 Scent hunting 4 Beagle Male ND 28.5 0.85 61.82 23259.63 Scent hunting 5 Beagle Male 4.0 8.3 0.82 61.82 66733.96 Scent hunting 6 Beagle Male 1.7 28.5 0.78 61.82 65738.93 Scent hunting 7 Bichon frise Male 9.0 9.3 0.80 61.51 61849.71 Explicit companionship 8 Border collie Male 6.1 28.2 0.65 54.38 83215.10 Herding 9 Border collie Male 5.6 20.6 0.65 54.38 81668.60 Herding 10 Boston terrier Male 11.9 12.5 0.90 92.62 66301.82 Explicit companionship Vermin control Sport fighting 11 Boston terrier Male 5.8 8.9 0.90 92.62 76426.61 Explicit companionship Vermin control Sport fighting 12 Boxer Male 8.1 31.8 0.68 67.19 81555.33 Guarding/protecting/sentinel work Police/military work, war Sport fighting 13 Boxer Male 5.0 34.2 0.67 67.19 80814.97 Guarding/protecting/sentinel work Police/military work, war Sport fighting 14 Boxer Female 10.7 31.8 0.83 66.28 93337.26 Guarding/protecting/sentinel work Police/military work, war Sport fighting 15 Boxer Male 9.3 40.8 0.70 67.19 82323.66 Guarding/protecting/sentinel work Police/military work, war Sport fighting 16 Bulldog Male 1.0 16.8 0.74 90.18 63154.13 Explicit companionship Sport fighting 17 Bulldog Male 4.4 30.0 0.77 90.18 80128.00 Explicit companionship Sport fighting 18 Cavalier King Charles spaniel Female 0.5 3.2 0.81 76.77 55777.97 Explicit companionship 19 Cavalier King Charles spaniel Female 0.5 14.5 0.92 76.77 64695.16 Explicit companionship 20 Cocker spaniel Female 6.4 18.1 0.75 61.01 66708.41 Bird retrieval 21 Dachshund Female 11.3 4.9 0.79 51.76 44076.29 Vermin control Scent hunting 22 Dachshund Female 6.6 6.4 0.77 51.76 60492.56 Vermin control Scent hunting 23 Dachshund Male 7.8 5.6 0.81 49.59 57168.79 Vermin control Scent hunting 24 Dachshund Female 1.8 5.3 0.81 51.76 49716.87 Vermin control Scent hunting 25 Doberman pinscher Female 4.7 29.8 0.62 46.96 80287.44 Guarding/protecting/sentinel work Police/military work, war 26 English Pointer Male 7.3 27.3 0.74 ND 91448.24 Bird retrieval 27 German short-haired pointer Female 6.2 27.0 0.73 48.30 75612.46 Bird retrieval 28 Golden retriever Male 10.0 39.8 0.69 56.52 96010.49 Bird retrieval 29 Golden retriever Male 6.0 42.2 0.70 56.52 96941.92 Bird retrieval 30 Golden retriever Male 11.0 34.9 0.68 56.52 86438.69 Bird retrieval 31 Greyhound Female 7.5 36.7 0.65 45.83 97610.47 Sight hunting 32 Greyhound Male 3.8 37.1 0.65 46.84 97774.89 Sight hunting 33 Greyhound Female 2.2 36.0 0.66 45.83 101969.38 Sight hunting 34 Jack Russell terrier Male ND 14.0 0.80 59.28 70125.35 Vermin control 35 Keeshond Male 7.2 21.6 0.71 60.18 68766.94 Explicit companionship Guarding/protecting/sentinel work 36 Labrador retriever Male 9.7 32.6 0.65 55.82 94762.33 Bird retrieval 37 Labrador retriever Female 5.0 30.5 0.66 56.11 84161.70 Bird retrieval 38 Lhasa apso Female 10.7 13.2 0.93 ND 58177.18 Guarding/protecting/sentinel work 39 Lhasa apso Female 4.0 7.6 0.86 ND 58152.92 Guarding/protecting/sentinel work 40 Maltese Male 6.6 6.0 0.81 65.29 46642.03 Explicit companionship 41 Maltese Male 10.0 3.0 0.84 65.29 35280.20 Explicit companionship 42 Maltese Male 5.5 6.6 0.77 65.29 46629.97 Explicit companionship 43 Maltese Male 6.0 8.9 0.88 65.29 47610.27 Explicit companionship 44 Maltese Female 6.0 2.0 0.92 68.83 28052.45 Explicit companionship 45 Maltese Female 4.9 3.4 0.85 68.83 46330.73 Explicit companionship 46 Miniature schnauzer Male 9.4 12.8 0.77 51.79 62053.63 Vermin control 47 Miniature schnauzer Female 6.3 5.0 0.80 54.99 53517.22 Vermin control 48 Old English sheepdog Male 3.7 33.1 0.69 54.39 80709.26 Herding 49 Pit bull Male 2.1 27.1 0.72 69.96 80571.31 Sport fighting 50 Siberian husky Female 3.0 18.1 0.67 55.17 62094.04 Running/racing 51 Silky terrier Male 3.0 4.4 0.84 58.23 46832.08 Vermin control 52 Springer spaniel Female 1.1 18.4 0.75 49.34 72442.26 Bird retrieval 53 Standard poodle Female 7.9 22.6 0.73 ND 80235.75 Bird retrieval 54 Weimaraner Male 3.3 48.4 0.66 49.05 110812.36 Sight hunting 55 Welsh corgi Male 5.6 15.1 0.72 63.09 83234.19 Herding 56 West highland white terrier Male 5.9 11.0 0.78 60.84 72254.08 Vermin control 57 Wheaton terrier Male 7.0 19.2 0.71 ND 70234.47 Guarding/protecting/sentinel work Herding Vermin control Bird retrieval 58 Whippet Female 15.5 13.6 0.72 50.60 71357.64 Sight hunting 59 Yorkshire terrier Female 3.8 3.9 0.82 ND 45103.02 Explicit companionship Vermin control 60 Yorkshire terrier Male 13.0 4.2 0.81 ND 45217.54 Explicit companionship Vermin control 61 Yorkshire terrier Male 0.8 3.5 0.79 ND 38163.05 Explicit companionship Vermin control 62 Yorkshire terrier Male 11.5 3.2 0.82 ND 51760.84 Explicit companionship Vermin control Dogs from mixed/unknown breeds were excluded from analyses that used breed group as an independent variable. Cephalic indices are sex- and breed-specific averages from a large public database (Stone et al., 2016).
ND, No data.
Figure 1-1
Conceptual schematic of neuroimaging analysis. Download Figure 1-1, TIF file
Figure 1-2
NiPype pipeline for merging axial and sagittal images from each dog before registration to the template. Code is available online at https://gist.github.com/dgutman/a0e05028fab9c6509a997f703a1c7413. Download Figure 1-2, TIF file
