The Consequences of Polyandry for Sibship Structures, Distributions of Relationships and Relatedness, and Potential for Inbreeding in a Wild Population

Ryan R. Germain, Peter Arcese, Jane M. Reid

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4 Citations (Scopus)
4 Downloads (Pure)

Abstract

The evolutionary benefits of simultaneous polyandry (female multiple mating within a single reproductive event) remain elusive. One potential benefit could arise if polyandry alters sibship structures and consequent relationships and relatedness among females’ descendants, thereby intrinsically reducing future inbreeding risk (the indirect inbreeding avoidance hypothesis). However such effects have not been quantified in naturally complex mating systems that also encompass iteroparity, overlapping generations, sequential polyandry, and polygyny. We used long-term social and genetic pedigree data from song sparrows (Melospiza melodia) to quantify cross-generational consequences of simultaneous polyandry for offspring sibship structures and distributions of relationships and relatedness among possible mates. Simultaneous polyandry decreased full sibships and increased half-sibships, on average, but such effects varied among females and were smaller than would occur in the absence of sequential polyandry or polygyny. Further, while simultaneous polyandry decreased the overall frequencies of possible matings among adult full sibs, it increased the frequencies of possible matings among adult half-sibs and more distant relatives. These results imply that the intrinsic consequences of simultaneous polyandry for inbreeding risk could cause weak indirect selection on polyandry, but the magnitude and direction of such effects will depend on complex interactions with other mating system components and the form of inbreeding depression.
Original languageEnglish
Pages (from-to)1-19
Number of pages19
JournalThe American Naturalist
Volume191
Issue number5
Early online date28 Feb 2018
DOIs
Publication statusPublished - May 2018

Fingerprint

polyandry
inbreeding
wild population
relatedness
polygyny
mating frequency
mating systems
reproductive strategy
inbreeding avoidance
distribution
multiple mating
Passeriformes
inbreeding depression
song
pedigree
animal communication

Keywords

  • extra-pair reproduction
  • inbreeding avoidance
  • kinship
  • monogamy
  • polyandry
  • relatedness

Cite this

The Consequences of Polyandry for Sibship Structures, Distributions of Relationships and Relatedness, and Potential for Inbreeding in a Wild Population. / Germain, Ryan R.; Arcese, Peter; Reid, Jane M.

In: The American Naturalist, Vol. 191, No. 5, 05.2018, p. 1-19.

Research output: Contribution to journalArticle

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