Survival of the Synesthesia Gene: Why Do People Hear Colors and Taste Words?
Figure 2
Average familial pedigrees for synesthetes composed from data in references [3],[18],[19],[23],[25],[48], demonstrating incidence of heritable transmission from one synesthetic parent (top row) to either a female or male child (bottom row).
Squares represent males and circles females. Color intensity reflects probability of synesthesia pedigree taken from the numbers at the bottom, representing incidence of each case.