Female choice of matings to maximise parental care.

Abstract

SUMMARYWe address the question of how many males a female should mate with in the context of species in which males provide care for potential offspring. Our analysis is based on the evolutionarily stable levels of parental effort of a female and a group of males. In the case of one female and two males we give a complete analysis of how the female's preference for monogamy or polyandry depends on the fitness functions assumed in the model. We then go on to consider the question of how many males a female should mate with to receive the highest level of male care. Our results are relevant in particular to the mating system of the dunnock (Prunella modularis) and also to the general question of whether a species should be monogamous as opposed to polyandrous.

Should advertising parental care be honest?

“…Positive correlations between female advertisement and her phenotypic quality are found in some species (MÖller 1993;Langmore et al 1996), but not in others (Hill 1993;Tella et al 1997), which suggests a possibility of obtaining multiple solutions in systems of mutual mate choice as well. Third, females may maximize care-provisioning not only by choosing a mate, but also by manipulating the number of matings with di¡erent males (Harada & Iwasa 1996;Houston et al 1997). This may also be linked with mutual mate choice and lead to female advertisement to maximize mate number (Langmore et al 1996).…”

Lonely hearts or sex in the city? Density-dependent effects in mating systems

“…H. Kokko & D. J. Rankin 325 ( Jennions & Petrie 2000). Whether a female is 'shopping for the best genes' (Evans & Magurran 2000;Bernasconi & Keller 2001;Hosken et al 2003;Ivy & Sakaluk 2005) or compatible genes (Tregenza & Wedell 2002), 'trading up' to find the best genetic or social mate (McNamara & Forslund 1996;Jennions & Petrie 2000), or mating with as many mates as possible (Takakura 1999) or with some intermediate optimum number (Houston et al 1997) for the sake of direct benefits, density can in every case influence the best strategy. In some cases, female mate preferences should change with density, not only in terms of the strength of the preference, but also its direction: males giving long or short calls should be preferred depending on density in grey tree frogs Hyla versicolor (Welch 2003), and female preferences in side-blotched lizards Uta stansburiana should likewise depend on the phase of the population cycle, as reproductive success of males depends on the types of morphs present in the population (Alonzo & Sinervo 2001;Sinervo & Zamudio 2001).…”

Sexual selection favours male parental care, when females can choose

“…While natural selection and evolutionary history clearly influence parental care evolution [3,4,9,10], recent theory examining sex differences in care has focused on how sexual selection interacts with parental investment. The general conclusion has been that, all else being equal, sexual selection on males disfavours the evolution of paternal care [1][2][3][4][5][6][7][8][9]11]. For males, uncertainty of paternity is argued to decrease the fitness benefit of caring for offspring (because the male is less related to the young in his care), while successful males are argued to lose mating success when they provide parental care [1][2][3][4][5][6][7][8][9]11].…”

“…The general conclusion has been that, all else being equal, sexual selection on males disfavours the evolution of paternal care [1][2][3][4][5][6][7][8][9]11]. For males, uncertainty of paternity is argued to decrease the fitness benefit of caring for offspring (because the male is less related to the young in his care), while successful males are argued to lose mating success when they provide parental care [1][2][3][4][5][6][7][8][9]11]. Male care is thus argued to evolve when natural selection (in the form of increased offspring survival) favouring parental care is stronger than sexual selection against male care [2][3][4][5].…”