Genetic control over sexual mimicry Sexual mimicry

paracerceis sculpta (marine isopod)

some organisms’ sexual mimicry genetically determined specific alleles. unlike sexual mimicry arises due molecular compounds or hormones , can induced through these molecules, sexual mimicry arises organism’s genetic material. besides female hyenas’ sexual anatomy, part of genetics, other organisms have males/females in population opposite sex , determined specific alleles.

in marine isopod population, paracerceis sculpta, there 3 different male morphologies: alpha male largest morph, matures last, , 1 gets privileged access females. beta male of intermediate size, , mimics female access females. last, gamma male smallest morph , invades harems, females go mate alpha males, mating opportunities. morphology associated single autosomal gene , 3 different alleles. beta dominant allele, followed gamma, followed alpha. selection on these alleles acts according hardy-weinberg equilibrium , mating success equivalent among 3 morphs.

the alpha males, homozygous alpha allele, mate many females in harem. females prefer aggregate other females in harem, gives alpha male bigger selection of mating partners. shuster (1992) looked @ behaviour , relationship of each morph respect harem , found beta , gamma males locate harems have sexually receptive females. able differentiate between harem sexually receptive female, i.e. 1 able mate, , non-sexually receptive female, i.e. 1 has deposited embryo pouch , can no longer mate. while still unclear how beta males or how mating strategies work, not harassed alpha males due mimicry of females: beta males can attract other females harem since females go other females are, , provides alpha males more mates.

another order of organisms sexual mimicry influenced dna odonata, carnivorous insects known dragonflies , damselflies. in these species, female mimics male. within species, groups of females differ in colour: 1 group mimics males’ colour , known androchromes. other groups have own female colouration , known gynochromes. in ischnura elegans, androchromes comprise 6-30% of female population , colour blue, males; in populations, androchromes larger in size gynochromes. polymorphism controlled autosomal allele , studies have looked @ reason polymorphism’s maintenance.

aeshna affinis male



aeshna affinis female androchrome

the theory maintenance of polymorphism in odonata density dependence theory states @ high male density, androchromes not bothered males , existence not threatened male harassment. hypothesis assumes males cannot distinguish between androchromes , other males. advantage, however, counteracted fact not lot of mating opportunities (if any) , reproduction limited. theory explanation maintenance of polymorphism, since studies have shown there advantage androchromes in high male-density populations.