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AbstractInsect societies vary greatly in their social structure, mating biology, and life history. Polygyny, the presence of multiple reproductive queens in a single colony, and polyandry, multiple mating by females, both increase the genetic variability in colonies of eusocial organisms, resulting in potential reproductive conflicts. The co-occurrence of polygyny and polyandry in a single species is rarely observed across eusocial insects, and these traits have been found to be negatively correlated in ants.Acromyrmexleaf-cutting ants are well-suited for investigating the evolution of complex mating strategies because both polygyny and polyandry co-occur in this genus. We used microsatellite markers and parentage inference in five South AmericanAcromyrmexspecies to study how different selective pressures influence the evolution of polygyny and polyandry. We show thatAcromyrmexspecies exhibit independent variation in mating biology and social structure, and polygyny and polyandry are not necessarily negatively correlated within genera. One species,Acromyrmex lobicornis, displays a significantly lower mating frequency compared to others, while another species,A. lundii, appears to have reverted to obligate monogyny. These variations appear to have a small impact on average intra-colonial relatedness, although the biological significance of such a small effect size is unclear. All species show significant reproductive skew between patrilines, but there was no significant difference in reproductive skew between any of the sampled species. We find that the evolution of social structure and mating biology appear to follow independent evolutionary trajectories in different species. Finally, we discuss the evolutionary implications that mating biology and social structure have on life history evolution inAcromyrmexleaf-cutting ants. Significance statementMany species of eusocial insects have colonies with multiple queens (polygyny), or queens mating with multiple males (polyandry). Both behaviors generate potentially beneficial genetic diversity in ant colonies as well as reproductive conflict. The co-occurrence of both polygyny and polyandry in a single species is only known from few ant species. Leaf-cutting ants have both multi-queen colonies and multiply mated queens, providing a well-suited system for studying the co-evolutionary dynamics between mating behavior and genetic diversity in colonies of eusocial insects. We used microsatellite markers to infer the socio-reproductive behavior in five South American leaf-cutter ant species. We found that variation in genetic diversity in colonies was directly associated with the mating frequencies of queens, but not with the number of queens in a colony. We suggest that multi-queen nesting and mating frequency evolve independently of one another, indicating that behavioral and ecological factors other than genetic diversity contribute to the evolution of complex mating behaviors in leaf-cutting ants.
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Development and characterization of microsatellite markers for Antennaria corymbosa (Asteraceae) and close relatives
PremiseThe genusAntennariahas a complex evolutionary history due to dioecism, excessive polyploidy, and the evolution of polyploid agamic complexes. We developed microsatellite markers fromA. corymbosato investigate genetic diversity and population genetic structure inAntennariaspecies. Methods and ResultsTwenty‐four novel microsatellite markers (16 nuclear and eight chloroplast) were developed fromA. corymbosausing an enriched genomic library. Ten polymorphic nuclear markers were used to characterize genetic variation in five populations ofA. corymbosa. One to four alleles were found per locus, and the expected heterozygosity and fixation index ranged from 0.00 to 0.675 and −0.033 to 0.610, respectively. We were also able to successfully amplify these markers in five additionalAntennariaspecies. ConclusionsThese markers are promising tools to study the population genetics of sexualAntennariaspecies and to investigate interspecific gene flow, clonal diversity, and parentage ofAntennariapolyploid agamic complexes.
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- Award ID(s):
- 1745197
- PAR ID:
- 10461514
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Applications in Plant Sciences
- Volume:
- 7
- Issue:
- 6
- ISSN:
- 2168-0450
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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