Surrounding landscape, habitat and hybridization dynamics drive population structure and genetic diversity in the Saltmarsh Sparrow

Ornithological Applications, Journal Year: 2023, Volume and Issue: 125(4)

Published: July 5, 2023

Abstract Determining factors that shape a species’ population genetic structure is beneficial for identifying effective conservation practices. We assessed and diversity Saltmarsh Sparrow (Ammospiza caudacuta), an imperiled tidal marsh specialist, using 13 microsatellite markers 964 individuals sampled from 24 marshes across the breeding range. show populations are structured regionally by isolation-by-distance, with gene flow occurring among within ~110 to 135 km of one another. Isolation-by-resistance isolation-by-environment also variation; several habitat landscape features associated divergence populations. Human development in surrounding isolates marshes, reducing diversity, increasing divergence, while marshland patch quality (proportion high sea-level-rise trend) have opposite effect. The distance Atlantic Ocean influences variation, farther inland being more divergent than coastal marshes. In northern hybridization Nelson’s (A. nelsoni) strongly population; this has concomitant effect differentiation levels introgression. From perspective, we found majority clusters low sizes, suggesting lack resiliency. To conserve representative breadth ecological ensure redundancy populations, it will be important protect types latitudinal gradient species range, including multiple inland, coastal, urban which shown exhibit signals differentiation. It require maintaining connectivity at regional level, promoting scale (~130 km), ensuring “stepping stone”

Language: Английский

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Genomic data reveal the biogeographical and demographic history of Ammospiza sparrows in northeast tidal marshes

Journal of Biogeography, Journal Year: 2021, Volume and Issue: 48(9), P. 2360 - 2374

Published: July 13, 2021

Abstract Aim Shaped by climate change and sea‐level rise, tidal salt marshes represent ephemeral systems that are home to only a few species. The dynamic ecological histories of these habitats, however, render it challenging reconstruct the complete biogeographical their endemic taxa. To better understand evolutionary history marsh sparrows, we employ genomic data evaluate timing direction colonization events leverage test series models describing our study Location North America. Taxon Ammospiza Sparrows. Methods We sampled 54 individuals from clade freshwater saltwater habitats. sequenced whole genomes generated dataset containing 21 million SNPs. Detailed phylogenomic analyses were conducted identify relationships between These phylogenies then used date divergence times as well historic signals introgression. Results Phylogenies based on several SNPs supported well‐resolved clades correspond all previous species designations. Demographic modelling within A. nelsoni provided further resolution into subspecies topology. Phylogenetic reconstructions support events, with some taxa exhibiting associations habitat over longer time‐scales transitions occurring recently 5,000 years ago. Main Conclusions Biogeographical an original origin sparrows currently inhabiting in also found strong evidence for transition n. subvirgatus opposed long hypothesized this group. conclude increased paired integrative framework phylogenomic, demographic is important resolving complex environments.

Language: Английский

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Temperature heterogeneity correlates with intraspecific variation in physiological flexibility in a small endotherm

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2020, Volume and Issue: unknown

Published: Nov. 17, 2020

ABSTRACT Phenotypic flexibility allows individuals to reversibly modify trait values and theory predicts an individual’s relative degree of positively correlates with the environmental heterogeneity it experiences. We tested this prediction by integrating surveys population genetic physiological variation thermal acclimation experiments indices in Dark-eyed Junco ( hyemalis ) its congeners. combined measures thermogenic capacity for ~300 individuals, >21,000 single nucleotide polymorphisms genotyped 192 laboratory acclimations replicated on five populations. found that populations: (1) differ their performance responses temperature situ ; (2) exhibit intra-specific native environment; (3) harbor also heterogeneity. These results provide comprehensive support phenotypic corresponds highlight importance coping change.

Language: Английский

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