THE DYNAMICS OF MALE BROODING, MATING PATTERNS, AND SEX ROLES IN PIPEFISHES AND SEAHORSES (FAMILY SYNGNATHIDAE)

@inproceedings{Wilson2003THEDO,
  title={THE DYNAMICS OF MALE BROODING, MATING PATTERNS, AND SEX ROLES IN PIPEFISHES AND SEAHORSES (FAMILY SYNGNATHIDAE)},
  author={Anthony B. Wilson and Ingrid Ahnesj{\"o} and Amanda C. J. Vincent and Axel Meyer},
  booktitle={Evolution; international journal of organic evolution},
  year={2003}
}
Abstract Modern theory predicts that relative parental investment of the sexes in their young is a key factor responsible for sexual selection. Seahorses and pipefishes (family Syngnathidae) are extraordinary among fishes in their remarkable adaptations for paternal care and frequent occurrences of sex-role reversals (i.e., female-female competition for mates), offering exceptional opportunities to test predictions of sexual selection theory. During mating, the female transfers eggs into or… 
Postcopulatory Sexual Selection and the Evolution of Male Pregnancy in the Gulf Pipefish
TLDR
The data suggests that male Gulf pipefish sacrifice investment in future reproduction, via somatic growth, in favor of current reproduction, and a relationship between number of failed eggs and male growth rate in low-food tr ea ments suggests that males may derive an energetic benefit from unsuccessful eggs in the brood pouch.
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 Role of Courtship Behavior and Size in Mate Preference in the Sex-Role-Reversed Gulf Pipefish, Syngnathus scovelli
TLDR
It was found that male mating preference was significantly associated with female courtship behavior and larger females were also able to maintain these behaviors for longer intervals than smaller females.
Sexual selection on female ornaments in the sex‐role‐reversed Gulf pipefish (Syngnathus scovelli)
TLDR
Results show that sexual selection favours either many bands or larger bands in female Gulf pipefish, and selection on female body size appears to be indirect, as evidenced by a multivariate analysis of selection gradients.
Reproductive behaviors and sex roles during a diurnal cycle of the goby, Lythrypnus pulchellus (Teleostei: Gobiidae)
TLDR
The frequencies and durations of reproductive behaviors of both males and females decreased according to time of day in both biased sex ratio experiments, except for the courtship behaviors ‘Nest approach’ in females and “Nest defense” in males that increases throughout the day.
Reproductive migrations of the sex role reversed pipefish Nerophis lumbriciformis(Pisces; Syngnathidae)
TLDR
W worm pipefish Nerophis lumbriciformis is a clearly dimorphic species in spite of the observed polygynandry, suggesting that differences in remating intervals may be influential in determining the strength of sexual selection along with what may be expected from thepolygynandrous mating system alone.
Differential parental nutrient allocation in two congeneric pipefish species (Syngnathidae: Syngnathus spp.)
TLDR
Results indicate gross classification of brooding structures into one of the three general pouch types does not predict the energetic investment of males in parental care and physiological characterization of the relative investment by each sex to offspring is essential to understanding the functional significance of the brood pouch.
Sexual signals and mating patterns in Syngnathidae.
TLDR
Cases are presented here suggesting that stronger sexual selection on females may be most extreme in species showing classical polyandry, intermediate in polygynandrous species and least extreme, even exhibiting conventional sex roles, in monogamous species.
implications of different brood pouch structures in syngnathid reproduction
TLDR
Observations suggest that the sealed seahorse pouch, although allowing the transport of a great number of offspring and capable of multiple consecutive pregnancies, may impose serious functional constraints, namely those related with oxygenation of the developing larvae, thus explaining the increased egg surface together with the presence of specific salinity control mechanisms inside the marsupium.
Genetic monogamy despite social promiscuity in the pot‐bellied seahorse (Hippocampus abdominalis)
TLDR
Investigating mating systems and brood parentage of the pot‐bellied seahorse, Hippocampus abdominalis, a temperate‐water species that is socially promiscuous with conventional sex roles in laboratory populations hypothesize that sex roles are plastic in H. abdominalis.
...
...

References

SHOWING 1-10 OF 82 REFERENCES
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.
Male pregnancy in seahorses and pipefishes (family Syngnathidae): rapid diversification of paternal brood pouch morphology inferred from a molecular phylogeny.
TLDR
A combined cytochrome b, 12S rDNA-, and 16S r DNA-based molecular phylogeny of syngnathid fishes demonstrates that rapid diversification of male brooding structures has been associated with the major evolutionary radiation of the group, suggesting that development and diversified of structures involved in paternal care may have been key evolutionary innovations of the SyngnATHidae.
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.
Operational sex ratios and behavioural sex differences in a pipefish population
TLDR
Mating behaviour in the wild of this pipefish is described and the hypothesis that temporal variations in the operational sex ratio (OSR) determine sex differences in mating behaviour is tested, demonstrating that behaviours associated with female-female competition are more prominent when the OSR is more female-biased.
The genetic mating system of a sex-role-reversed pipefish (Syngnathus typhle): a molecular inquiry
TLDR
Preliminary support is provided for the hypothesis that the genetic mating system of S. typhle is related to the evolution of sexual dimorphism in the fish family Syngnathidae.
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.
Monogamy and sex role reversal in the pipefish Corythoichthys haematopterus
TLDR
It is suggested that mate guarding by females is a primary proximate factor for maintenance of monogamy in this fish and provides the first example of sex role reversal among monogamous syngnathid fish.
Differences in potential reproductive rates of male and female seahorses related to courtship roles
TLDR
Results and previous work indicating that seahorses display traditional courtship roles support the prediction that the sex having the higher potential reproductive rate, or equivalently, the shorter 'time out', will compete more intensely for access to the opposite sex.
Brooding season, sex ratio, and brood pouch development in the seaweed pipefish, Syngnathus schlegeli, in Otsuchi Bay, Japan
TLDR
Results seem to collectively indicate that the occurrence of a larger proportion of immature males at the onset of the reproductive season may be ascribed to both new recruitment and larger body size at maturation, resulting from the males trading the reproductive effort to somatic growth, perhaps to increase future reproductive success.
Experimental reversal of courtship roles in an insect
TLDR
It is confirmed and shown that an increase in food from a low level results in a change from role-reversal to the typical roles, which supports the theory that variation in relative male parental investment controls sexual differences.
...
...