▁typical ▁eye ▁color ▁of ▁D ros oph ila ▁mel an og aster . ▁These ▁mut ations ▁occur ▁on ▁the ▁third ▁chrom os ome . ▁It ▁is ▁due ▁to ▁the ▁in ability ▁of ▁the ▁sep ia ▁to ▁manufact ure ▁a ▁p ter id ine ▁en zym e ▁that ▁is ▁responsible ▁for ▁the ▁red ▁p ig ment ation , ▁that ▁they ▁are ▁unable ▁to ▁display ▁the ▁red ▁color ation ▁of ▁the ▁eyes , ▁and ▁instead ▁have ▁the ▁brown ▁color ation ▁as ▁mentioned ▁earlier . ▁When ▁m ated ▁with ▁a ▁wild ▁type , ▁f lies ▁with ▁red ▁eyes ▁will ▁be ▁dominant ▁over ▁sep ia ▁color ▁eyes . ▁They ▁are ▁then ▁class ified ▁as ▁a ▁re cess ive ▁mut ation , ▁and ▁can ▁only ▁result ▁when ▁both ▁chrom os om es ▁contain ▁the ▁gene ▁for ▁sep ia ▁eyes . ▁Sep ia ▁colored ▁eyes ▁are ▁not ▁dependent ▁on ▁the ▁sex ▁of ▁the ▁fly . ▁The ▁Sep ia ▁eye ▁color ▁decre ases ▁sexual ▁activity ▁in ▁males ▁and ▁influ ences ▁preference ▁of ▁females .” ▁ ▁v : ▁verm il ion - ▁Verm il ion ▁eye ▁color ▁compared ▁to ▁a ▁wild ▁type ▁D . ▁mel an og aster ▁is ▁a ▁radi ant ▁red . ▁Verm il ion ▁eye ▁color ▁mut ant ▁is ▁sex - link ed ▁re cess ive ▁gene ▁due ▁to ▁its ▁absence ▁of ▁brown ▁eye ▁p ig ment . ▁The ▁red ▁p ig ment ▁is ▁located ▁on ▁the ▁X ▁chrom os ome . ▁The ▁synth esis ▁of ▁brown ▁p ig ment ▁is ▁due ▁to ▁the ▁process ▁of ▁converting ▁try