How Female-Female Competition Affects Male-Male Competition: Insights into Postcopulatory Sexual Selection from Socially Polyandrous Species

The American Naturalist, Journal Year: 2022, Volume and Issue: 201(3), P. 460 - 471

Published: Oct. 4, 2022

AbstractSexual selection is a major driver of trait variation, and the intensity male competition for mating opportunities has been linked with sperm size across diverse taxa. Mating among females may also shape evolution traits, but effect interplay between female-female male-male on morphology not well understood. We evaluated variation in two species socially polyandrous systems, which compete to mate multiple males. Northern jacanas (Jacana spinosa) wattled (J. jacana) vary their degree social polyandry sexual dimorphism, suggesting differences selection. compared mean variance head, midpiece, tail length breeding stages because these measures have associated competition. found that greater polyandry, northern jacana, longer midpieces tails as marginally lower intraejaculate length. Intraejaculate was significantly copulating males than incubating males, flexibility production cycle stages. Our results indicate stronger more intense by selecting less variable traits. These findings extend frameworks developed monogamous reveal be an important evolutionary force layered atop mates.

Language: Английский

---

Sperm length divergence as a potential prezygotic barrier in a passerine hybrid zone

Ecology and Evolution, Journal Year: 2021, Volume and Issue: 11(14), P. 9489 - 9497

Published: June 16, 2021

Abstract The saltmarsh sparrow Ammospiza caudacuta and Nelson's A. nelsoni differ in ecological niche, mating behavior, plumage, but they hybridize where their breeding distributions overlap. In this advanced hybrid zone, past interbreeding current backcrossing result substantial genomic introgression both directions, although few hybrids are currently produced most locations. However, because species nonterritorial have only brief male–female interactions, it is difficult to determine what extent assortative explains the low frequency of offspring. Since females often copulate with multiple males, a role sperm as postcopulatory prezygotic barrier appears plausible. Here, we show that length differs between two among‐male variation consistent strong sexual selection on cells. We hypothesize divergence may constitute reproductive species, co‐evolves size specialized female storage tubules. Sperm does not appear act postzygotic barrier, from was unexceptional.

Language: Английский

---

Early diversification of sperm size in the evolutionary history of the old world leaf warblers (Phylloscopidae)

Journal of Evolutionary Biology, Journal Year: 2016, Volume and Issue: 29(4), P. 777 - 789

Published: Jan. 19, 2016

Abstract Sperm morphological traits are highly variable among species and commonly thought to evolve by post‐copulatory sexual selection. However, little is known about the evolutionary dynamics of sperm morphology, whether rates change over time taxonomic groups. Here, we examine morphology from 21 Old World leaf warblers (Phylloscopidae), a group generally dull, sexually monochromatic birds, which have high levels extra‐pair paternity. We found that length differs markedly across species, spanning 40% range observed larger selection passerine birds. Furthermore, strong support for an ‘early‐burst’ model trait evolution, implying majority divergence in has occurred early history this clade with subsequent stasis. This large matches reported ecological (i.e. body size feeding behaviour). Our findings demonstrate evolution can taxa, stasis occur even exhibiting characteristics consistent moderate‐to‐high competition. It remains major challenge identify mechanisms possible constraints responsible these evolution.

Language: Английский

---

Song complexity is associated with habitat quality in an upland passerine

Ibis, Journal Year: 2023, Volume and Issue: 166(2), P. 682 - 693

Published: July 18, 2023

Understanding the influence of intrinsic (genetic and morphological) extrinsic (geographical, environmental social) factors on performance spatial differentiation sexual signals, such as bird song, can help identify behavioural indicators individual quality, habitat degradation social environment. We used Iberian Bluethroat Luscinia svecica azuricollis , a migratory that breeds in fragmented landscapes dominated by shrublands, case study to: (1) assess how set acoustic song are driven factors; (2) contrast deterministic (adaptations to context morphological constraints) vs. stochastic (differentiation geographical isolation) explanations for patterns. explored (spectral, temporal complexity) relation parameters related genetic structure, body size, type, quality (assessed through spatially explicit modelling approach) (population abundance songbird community composition). Then, we contribution genetic, dissimilarity diversification across space. Our results highlight an association spectral variables with structure significant connection between complexity duration quality. found no relationship features variables, or distances. There was, however, correlation dissimilarity. recommend consideration indicator

Language: Английский

---

Weak geographical structure in sperm morphology across the range of two willow warbler Phylloscopus trochilus subspecies in Scandinavia

Journal of Avian Biology, Journal Year: 2016, Volume and Issue: 47(5), P. 731 - 741

Published: March 12, 2016

Sperm morphology is highly diversified among species and at higher taxonomic levels. In birds, there also increasing evidence of geographical differentiation in sperm traits within species, especially those with strong competition. Geographical divergences might imply the formation a reproductive barrier speciation process. Here we study variation willow warblers Phylloscopus trochilus context Scandinavia, across range two subspecies that are differentiated certain genetic markers, migratory routes. We describe patterns genotypes (two previously described single‐nucleotide polymorphism (SNP) markers four polymorphic microsatellites); wing length, tarsus length body mass; 330 male sampled 33 localities Norway (58°N–69°N). Birds were on average larger longer‐winged north (spp. acredula ) than south ), showed sigmoid change SNP allele frequencies around 65°N. found no structuring microsatellites. There was Norway, except heads longer south. head associated for southern alleles, midpiece weakly one markers. Similar among‐male variances total sampling sites indicate uniform levels competition Norway. conclude remains rather undifferentiated trait between warbler which consistent pattern shallow divergence. This indicates not maintaining narrow hybrid zone.

Language: Английский

---