The asexual, all-female Whiptail lizard
species Cnemidophorus neomexicanus
(center), which reproduces via parthenogenesis
, is shown flanked by two sexual species having males, C. inornatus
(left) and C. tigris
(right). Research has shown that simulated mating behavior increases fertility for Cnemidophorus neomexicanus. One female lies on top of another, playing the role of the male, the lizard that was on bottom has larger eggs. The lizards switch off this role each mating season.
Male homosexuality has been inferred in several species of dragonflies. A survey of damsel and dragonflies reveals characteristic cloacal pincher mating damage in 20–80 percent of the males, indicating a fairly high occurrence of sexual coupling between males.
Selected mammals from the full list
Selected birds from the full list