Figure 6.

Domestication leads to a drastic reduction of the brain size in its entirety and regionally. (A) Overall brain anatomy at the same scale illustrated in lateral view for the goldfish closest to its wild counterparts, i.e., common goldfish, and one of the most distant, i.e., Bubble-eye breed. Brains show parcellated coloration to illustrate the different brain regions. (B) Histogram of relative brain volume and related relative regions volumes, with one being the closest relative to wild counterparts, i.e., common goldfish, and five being the most distant, i.e., Celestial breed (see Figure 4 for the five-breed selection). Total brain volume was standardized using neurocranial centroid size, while each brain region was standardized by total brain volume. Asterisks indicate brain region subject to distinct volume trends between common goldfish and other breeds. The color code in (B) follows the color code from (A). Fish illustrations are not scaled, and references are available in Supplementary Table S7.