skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Life‐history stage and the population genetics of the tiger mosquito Aedes albopictus at a fine spatial scale
Abstract As a widespread vector of disease with an expanding range, the mosquitoAedes albopictusSkuse (Diptera: Culicidae) is a high priority for research and management.A. albopictushas a complex life history with aquatic egg, larval and pupal stages, and a terrestrial adult stage. This requires targeted management strategies for each life stage, coordinated across time and space. Population genetics can aid inA. albopictuscontrol by evaluating patterns of genetic diversity and dispersal. However, how life stage impacts population genetic characteristics is unknown. We examined whether patterns ofA. albopictusgenetic diversity and differentiation changed with life stage at a spatial scale relevant to management efforts. We first conducted a literature review of field‐caughtA. albopictuspopulation genetic papers and identified 101 peer‐reviewed publications, none of which compared results between life stages. Our study uniquely examines population genomic patterns of egg and adultA. albopictusat five sites in Wake County, North Carolina, USA, using 8425 single nucleotide polymorphisms. We found that the level of genetic diversity and connectivity between sites varied between adults and eggs. This warrants further study and is critical for research aimed at informing local management.  more » « less
Award ID(s):
1754376
PAR ID:
10484755
Author(s) / Creator(s):
; ;
Publisher / Repository:
Royal Entomological Society
Date Published:
Journal Name:
Medical and Veterinary Entomology
Volume:
37
Issue:
1
ISSN:
0269-283X
Page Range / eLocation ID:
132 to 142
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract Parental care, mating dynamics and life history co‐evolve. Understanding the diversity of reproductive patterns found in nature is a major focus of evolutionary ecology research. Previous research suggests that the origin of parental care of eggs will be favoured when egg and adult death rates and juvenile survival are relatively high. However, the previous research that explored the link between care and life history did not account for among‐species variation in mating dynamics. As mating dynamics are generally expected to influence care, we explore, theoretically, the life‐history conditions (stage‐specific rates of maturation and survival) that favour parental care across three mating scenarios: reproductive rate (1) is unaffected by males (assuming that some males are present), (2) increases as male abundance increases or (3) decreases as male abundance increases. Across scenarios, all forms of care were most strongly favoured when egg and adult death rates, juvenile survival and female egg maturation rates were relatively high. When reproductive rate was unaffected by male abundance or increased as male abundance increased, as we might expect in systems in which females are mate‐limited, all forms of care were most strongly favoured when male egg maturation rate (i.e. the rate at which male eggs develop, mature and hatch) was moderate or high. When greater male abundance inhibited reproduction, which might occur in systems with intense male–male competition, all forms of care were most strongly favoured when male egg maturation rate was low‐to‐moderate. These results suggest that life history affects the evolution of parental care, and sex‐specific life history can interact with mating dynamics to influence the origin of care. 
    more » « less
  2. Abstract Adaptation to environmental change requires that populations harbor the necessary genetic variation to respond to selection. However, dispersal‐limited species with fragmented populations and reduced genetic diversity may lack this variation and are at an increased risk of local extinction. In freshwater fish species, environmental change in the form of increased stream temperatures places many cold‐water species at‐risk. We present a study of rainbow darters (Etheostoma caeruleum) in which we evaluated the importance of genetic variation on adaptive potential and determined responses to extreme thermal stress. We compared fine‐scale patterns of morphological and thermal tolerance differentiation across eight sites, including a unique lake habitat. We also inferred contemporary population structure using genomic data and characterized the relationship between individual genetic diversity and stress tolerance. We found site‐specific variation in thermal tolerance that generally matched local conditions and morphological differences associated with lake‐stream divergence. We detected patterns of population structure on a highly local spatial scale that could not be explained by isolation by distance or stream connectivity. Finally, we showed that individual thermal tolerance was positively correlated with genetic variation, suggesting that sites with increased genetic diversity may be better at tolerating novel stress. Our results highlight the importance of considering intraspecific variation in understanding population vulnerability and stress response. 
    more » « less
  3. null (Ed.)
    Interactions among selection, gene flow, and drift affect the trajectory of adaptive evolution. In natural populations, the direction and magnitude of these processes can be variable across different spatial, temporal, or ontogenetic scales. Consequently, variability in evolutionary processes affects the predictability or stochasticity of microevolutionary outcomes. We studied an intertidal fish, Bathygobius cocosensis (Bleeker, 1854), to understand how space, time, and life stage structure genetic and phenotypic variation in a species with potentially extensive dispersal and a complex life cycle (larval dispersal preceding benthic recruitment). We sampled juvenile and adult life stages, at three sites, over three years. Genome-wide SNPs uncovered a pattern of chaotic genetic patchiness, that is, weak-but-significant patchy spatial genetic structure that was variable through time and between life stages. Outlier locus analyses suggested that targets of spatially divergent selection were mostly temporally variable, though a significant number of spatial outlier loci were shared between life stages. Head shape, a putatively ecologically responsive (adaptive) phenotype in B. cocosensis also exhibited high temporal variability within sites. However, consistent spatial relationships between sites indicated that environmental similarities among sites may generate predictable phenotype distributions across space. Our study highlights the complex microevolutionary dynamics of marine systems, where consideration of multiple ecological dimensions can reveal both predictable and stochastic patterns in the distributions of genetic and phenotypic variation. Such considerations probably apply to species that possess short, complex life cycles, have large dispersal potential and fecundities, and that inhabit heterogeneous environments. 
    more » « less
  4. Abstract Unisexual vertebrates typically form through hybridization events between sexual species in which reproductive mode transitions occur in the hybrid offspring. This evolutionary history is thought to have important consequences for the ecology of unisexual lineages and their interactions with congeners in natural communities. However, these consequences have proven challenging to study owing to uncertainty about patterns of population genetic diversity in unisexual lineages. Of particular interest is resolving the contribution of historical hybridization events versus post formational mutation to patterns of genetic diversity in nature. Here we use restriction site associated DNA genotyping to evaluate genetic diversity and demographic history inAspidoscelis laredoensis, a diploid unisexual lizard species from the vicinity of the Rio Grande River in southern Texas and northern Mexico. The sexual progenitor species from which one or more lineages are derived also occur in the Rio Grande Valley region, although patterns of distribution across individual sites are quite variable. Results from population genetic and phylogenetic analyses resolved the major axes of genetic variation in this species and highlight how these match predictions based on historical patterns of hybridization. We also found discordance between results of demographic modelling using different statistical approaches with the genomic data. We discuss these insights within the context of the ecological and evolutionary mechanisms that generate and maintain lineage diversity in unisexual species. As one of the most dynamic, intriguing, and geographically well investigated groups of whiptail lizards, these species hold substantial promise for future studies on the constraints of diversification in unisexual vertebrates. 
    more » « less
  5. Abstract The relative rates of sexual versus asexual reproduction influence the partitioning of genetic diversity within and among populations. During range expansions, asexual reproduction often facilitates colonization and establishment. The arrival of the green algaAvrainvillea laceratahas caused shifts in habitat structure and community assemblages since its discovery in 1981 offshore of Oʻahu, Hawai‘i. Field observations suggest this species is spreading via vegetative reproduction. To characterize the reproductive system ofA. laceratain Hawai‘i, we developed seven microsatellite loci and genotyped 321 blades collected between 2018 and 2023 from three intertidal sites at Maunalua Bay and ʻEwa Beach. We observed one to four alleles at multiple loci, suggestingA. laceratais tetraploid. Each site was characterized by high genotypic richness (R > 0.8). However, clonal rates were also high, suggesting the vegetative spread ofA. lacerataplays a significant role. The importance of clonal reproduction for the persistence ofA. laceratain Hawai‘i is consistent with the ecological data collected for this species and observations of other abundant macroalgal invaders in Hawai‘i and other regions of the world. These data demonstrate the necessity for implementing appropriate population genetic methods and provide insights into the biology of this alga that will contribute to future studies on effective management strategies incorporating its reproductive system. This study represents one of the few that investigate green algal population genetic patterns and contributes to our understanding of algal reproductive system evolution. 
    more » « less