[2] The different mating tactics employed by males and females are thought to be the outcome of stochastic reproductive conflicts both ecologically and socially.
[1] In dark-eyed juncos, a female mates with more than one male because oftentimes, her social partner is of lower genetic quality than other potential sperm donors.
[1] In song birds, extra-pair matings occur because females are able to sneak away from their home territories to solicit to other males.
Thus, when female song birds have multiple mating partners, they are increasing the genetic quality of their offspring.
[1] In dark-eyed juncos, dunnocks, and Galapagos hawks, mating with multiple males increases the amount of care a female can gain for her offspring.
[4] As of now, all species in the suborder Salamandroidea have shown to employ polyandrous mating strategies by females.
[4] In a study of a population of Salamandrina perspicillata, multiple paternity occurs as a pervasive reproductive strategy under natural conditions and it is seen that in these species, when males mated with two females, they sired offspring who were inversely related with their genetic similarity to the female.
[4] And like the case of Salamandrina perspicillata, there were no indirect genetic benefits gained from having multiple mating partners.
[5] A high level of paternity assurance is Ammothea hilgendorfi, suggests that reduced foraging ability, increased predation risk, and lower mobility exist.
In species with external fertilization and male parental care, females are able to distribute her clutch amongst different males and by doing so the female increases the likelihood that at least some of her offspring will receive indirect genetic benefits and/or extensive parental care from a quality provider.
A honey bee queen ideally mates with about a dozen drones (males) in her nuptial flight.
The sperm of matings are stored in a special reservoir, called the spermatheca, for the life of the queen—which can be several years.
In a study of female water striders, the results showed that multiple matings can become costly to the female—especially since a lot of time and energy is invested in producing an egg.
[7] On the other hand, studies have shown that males have had a higher reproductive success than females when they were polygynandrous.
Not only did studies show a higher reproductive success, but Columbian ground squirrels exhibited a significant male-biased sexual size and body mass, suggesting male-male competition.