The genetic mating system of a sex-role-reversed pipefish (Syngnathus typhle): a molecular inquiry

@article{Jones1999TheGM,
  title={The genetic mating system of a sex-role-reversed pipefish (Syngnathus typhle): a molecular inquiry},
  author={Adam G. Jones and Gunilla Rosenqvist and Anders Berglund and John C. Avise},
  journal={Behavioral Ecology and Sociobiology},
  year={1999},
  volume={46},
  pages={357-365}
}
Abstract In the pipefish Syngnathus typhle as in other species of Syngnathidae, developing embryos are reared on the male's ventral surface. Although much laboratory research has been directed toward understanding sexual selection in this sex-role-reversed species, few studies have addressed the mating behavior of S. typhle in the wild, and none has capitalized upon the power of molecular genetic assays. Here we present the first direct assessment of the genetic mating system of S. typhle in… 
Mating systems and sexual selection in male-pregnant pipefishes and seahorses: insights from microsatellite-based studies of maternity.
TLDR
Genetic studies of the genetic mating systems of pipefishes and seahorses have provided insights into important aspects of the natural history and evolution of these fishes, and suggest that the sexual selection gradient (or Bateman gradient) may be a substantially better method for characterizing the mating system than previously available techniques.
Genetic evidence for polygynandry in the black-striped pipefish Syngnathus abaster: a microsatellite-based parentage analysis.
TLDR
The mating system of the black-striped pipefish Syngnathus abaster is described, using 4 highly variable microsatellites to analyze parentage of 102 embryos and results support the hypothesis that the mating system is related to the intensity of sexual dimorphism.
Sexual size dimorphism predicts the frequency of multiple mating in the sex‐role reversed pipefish Syngnathus typhle
TLDR
Both sexes were larger and males had an increased brood size where water temperatures during the breeding season were lower, suggesting that disproportionate increases in female fecundity may be able to compensate for increased male brood pouch capacity.
THE DYNAMICS OF MALE BROODING, MATING PATTERNS, AND SEX ROLES IN PIPEFISHES AND SEAHORSES (FAMILY SYNGNATHIDAE)
TLDR
The data demonstrate that sex-role reversal is positively associated with polygamous mating patterns, whereas most nonreversed species mate monogamously, suggesting that selection for polygamy or monogamy in pipefishes and seahorses may strongly influence sex roles in the wild.
The genetic mating system and tests for cuckoldry in a pipefish species in which males fertilize eggs and brood offspring externally
TLDR
The genetic results suggest that the evolutionary elaboration of the enclosed brood pouch elsewhere in the family was probably not in response to selection pressures on pregnant males to avoid fertilization thievery, and the polyandrous genetic mating system in this species parallels the social mating system.
The Bateman gradient and the cause of sexual selection in a sex–role–reversed pipefish
TLDR
It is shown that, in the male–pregnant pipefish Syngnathus typhle, females exhibit a stronger positive association between number of mates and fertility than do males and that this relationship responds in the predicted fashion to changes in the adult sex ratio.
Genetic evidence for extreme polyandry and extraordinary sex-role reversal in a pipefish
TLDR
A DNA–based study of parentage in the Gulf pipefish Syngnathus scovelli is used to show that sexual selection indeed acts more strongly on females than on males in this species, and exhibits classical polyandry with the greatest asymmetry in reproductive roles yet documented in any system.
Mate quality influences multiple maternity in the sex‐role‐reversed pipefish Syngnathus typhle
TLDR
Results indicate that variation in female size can affect the mating system and thereby influence sexual selection in pipefish, and the high rate of multiple mating by S. typhle males in the wild may be explained in part by the extensive size variation in naturally occurring, sexually mature females.
Geographical variation in the mating system of the dusky pipefish (Syngnathus floridae)
TLDR
Comparisons of two geographically distinct populations of the dusky pipefish show that this species is a good model for the study of mating system variation in nature and that Bateman's principles may be a useful technique for the quantitative comparison of mating systems between populations.
...
...

References

SHOWING 1-10 OF 53 REFERENCES
POLYGYNANDRY IN THE DUSKY PIPEFISH SYNGNATHUS FLORIDAE REVEALED BY MICROSATELLITE DNA MARKERS
  • A. Jones, J. Avise
  • Biology
    Evolution; international journal of organic evolution
  • 1997
TLDR
The genetic results for S. floridae and S. scovelli are consistent with a simple model of sexual selection which predicts that for sex role‐reversed organisms, species with greater degrees of sexual dimorphism are more highly polyandrous.
Microsatellite analysis of maternity and the mating system in the Gulf pipefish Syngnathus scovelli, a species with male pregnancy and sex‐role reversal
TLDR
Highly variable microsatellite loci were employed to study the mating system of the sexually dimorphic Gulf pipefish Syngnathus scovelli, and it was determined that only one male had received eggs from more than a single female; and on two separate occasions, two different males had receiving eggs from the same female.
Clustered microsatellite mutations in the pipefish Syngnathus typhle.
TLDR
Observations on clustered mutations to another organismal group are extended and motivated to motivate a broader critique of the mutation cluster phenomenon and carry implications for the evolution of microsatellites with respect to mutational models and homoplasy among alleles.
Consequences of male brood care; weight and number of newborn in a sex-role reversed pipefish
TLDR
Results indicate that in S. typhle, male reproductive success is limited by their own brooding ability and influenced by the egg size received (indirectly quality of mate), which may be expected in a situation of sex-role reversal.
Reproductive Success of Females Limited by Males in Two Pipefish Species
We investigate whether males limit the reproductive success of females in the two pipefish species Syngnathus typhle and Nerophis ophidion. Syngnathus typhle is sexually monomorphic, and courtship
Cuckoldry through stored sperm in the sequentially polyandrous spotted sandpiper
TLDR
It is reported that males pairing early in the season cuckold their females' later mates by means of stored sperm, and early-pairing males not only have greater confidence of paternity, but also increase their reproductive success by fertilizing a proportion of eggs laid for, and incubated by, their Females' subsequent mates, in addition to those they incubate themselves.
Male avoidance of parasitized females explained by direct benefits in a pipefish
TLDR
There was a negative correlation between parasite load and female fecundity, and males mating with unparasitized females may benefit directly by fertilizing more eggs.
Microsatellite evidence for monogamy and sex‐biased recombination in the Western Australian seahorse Hippocampus angustus
TLDR
Four polymorphic microsatellite loci were used to assess biological parentage of 453 offspring from 15 pregnant males from a natural population of the Western Australian seahorse Hippocampus angustus, consistent with a monogamous mating system in which both females and males had a single mate during a male brooding period.
A MICROSATELLITE ASSESSMENT OF SNEAKED FERTILIZATIONS AND EGG THIEVERY IN THE FIFTEENSPINE STICKLEBACK
TLDR
The genetic data demonstrated that nests of males frequently contain eggs from multiple females, and the multilocus genotypes of inferred mothers indicated that females mate with multiple males, sometimes over distances greater than one kilometer.
DNA fingerprinting of bluegill sunfish (Lepomis macrochirus) using (GT)n microsatellites and its potential for assessment of mating success
TLDR
This work cloned and characterized 60 (GT) repeat microsatellite sequences from the bluegill sunfish genome and found seven loci are potentially highly informative for fingerprinting studies of parentage, potentially allowing DNA fingerprinting of a variety of centrarchids.
...
...