Effects of sex on total tissue volume (TTV) in humans and mice.

Distributions of TTV are shown for the effects of sex in humans (A) and mice (B). Data are represented using individual points, boxplot, and half-violin plot. ***p<0.0001. M= male, F=female.

Effect of sex on regional brain volume in humans and mice.

A, B. Distribution of sex-biased standardized effect sizes across anatomical regions for humans (A) and mice (B). C, D. Unthresholded (left) and significant (q<0.05; right) standardized effect sizes for the effect of sex displayed on the human (C) and mouse (D) brains. Regions in yellow-red are male-biased and regions in blue are female-biased.

Correlation of sex effects on regional volume in homologous regions of the human and mouse brain.

A. Standardized effect size correlation for the effect of sex in humans (x-axis) and mice (y-axis) (robust correlation coefficient, r=0.30). B. Correlation of standardized effect sizes for the effect of sex across species for cortical regions (green, r=0.31), and non-cortical regions (purple, r=0.16).

Species-specific effect sizes for volumetric sex differences for 60 homologous brain regions.

Effect sizes are color coded (blue: male-biased / yellow: female-biased) and asterisk/bold text denotes statistical significance. All results are from analyses covarying for TTV.

Homologous brain regions showing either congruent or divergent sex bias across species.

There are no regions that are larger in human females and mouse males (top left quadrant, light green). Several regions show male-bias (top right quadrant in yellow) and female-bias (bottom left quadrant in blue) across species. A subset of regions show male-bias in humans but female bias in mice (bottom right quadrant in green). * Denotes significant sex effect in both species. Ordering of quadrants matches quadrants of the scatter plots in Figures 3 and 5.

Inter-species anatomical sex congruence and gene expression shows modest correlation across homologous brain regions.

Correlation between similarity in volumetric sex differences and similarity in transcriptional profile using all homologous genes across all homologous regions modest (A). There was a stronger correlation across cortical (green) compared to non-cortical (purple) regions (B).