Sex-ratio-variation
Guides
Myrmica tahoensis
A facultatively polygynous ant species in the genus Myrmica, native to the Rocky Mountain region of North America. Population-level sex ratios show pronounced temporal variation across years, with female-biased sexual production in odd-numbered years and male-biased production in even-numbered years. Individual colonies tend to maintain consistent sex ratio patterns across consecutive years. The species has been studied primarily at the Rocky Mountain Biological Laboratory in Colorado.
Phytomyza plantaginis
Plantain leafminer
Phytomyza plantaginis is a leaf-mining fly in the family Agromyzidae. It is notable as the second documented case of parthenogenetic reproduction (thelytoky) in its family. Populations in Australia exhibit variation in sex ratio, with some areas having only females and others maintaining bisexual populations with female-biased ratios. The species is associated with Plantago host plants.