Do genetic structure and landscape heterogeneity impact color morph frequency in a polymorphic salamander?

AbstractGlobal aquatic habitats are undergoing rapid degradation and fragmentation as a result of land-use change and climate change. Understanding the genetic variability and adaptive potential of aquatic plant species is thus important for conservation purposes. In this study, we investigated the role of environment, landscape heterogeneity and geographical distance in shaping the genetic structure of 28 natural populations of Zizania latifolia (Griseb.) Turcz. Ex Stapf in China based on 25 microsatellite markers. Genetic structure was investigated by analysis of molecular variance (AMOVA), estimation of FST, Bayesian clustering and Thermodynamic Integration (TI) methods. Isolation by environment (IBE), isolation by resistance (IBR) and isolation by distance (IBD) hypotheses were compared using a reciprocal causal model (RCM). Further, generalized linear models and spatially explicit mixed models, by using geographic, landscape and genetic variables, were developed to elucidate the role of environment in driving Z. latifolia genetic diversity. The genetic differentiation across all populations was high: FST = 0.579; Øpt = 0.578. RCM exclusively supported IBE in shaping genetic structuring, only partial support for IBR, but not for IBD. Maximum temperature of the warmest month and precipitation seasonality were the plausible parameters responsible for genetic diversity. After controlling for spatial effect and landscape complexity, precipitation seasonality was significantly associated with genetic diversity. Based on these findings, genetic structure of Z. latifolia across China seem to be as a result of local adaptation. Environmental gradient and topographical barriers, rather than geographical isolation, influence genetic differentiation of aquatic species across China resulting in instances of local adaptation.

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Recent range expansion and agricultural landscape heterogeneity have only minimal effect on the spatial genetic structure of the plant pathogenic fungus Mycosphaerella fijiensis

Heredity ◽

10.1038/hdy.2012.55 ◽

2012 ◽

Vol 110 (1) ◽

pp. 29-38 ◽

Cited By ~ 13

Author(s):

A Rieux ◽

L De Lapeyre De Bellaire ◽

M-F Zapater ◽

V Ravigne ◽

J Carlier

Keyword(s):

Genetic Structure ◽

Range Expansion ◽

Agricultural Landscape ◽

Landscape Heterogeneity ◽

Spatial Genetic Structure ◽

Pathogenic Fungus ◽

Minimal Effect ◽

Mycosphaerella Fijiensis ◽

Plant Pathogenic Fungus

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Landscape heterogeneity and local adaptation define the spatial genetic structure of Pacific salmon in a pristine environment

Conservation Genetics ◽

10.1007/s10592-012-0401-7 ◽

2012 ◽

Vol 14 (2) ◽

pp. 483-498 ◽

Cited By ~ 17

Author(s):

Michael W. Ackerman ◽

William D. Templin ◽

James E. Seeb ◽

Lisa W. Seeb

Keyword(s):

Genetic Structure ◽

Local Adaptation ◽

Landscape Heterogeneity ◽

Pacific Salmon ◽

Spatial Genetic Structure ◽

Pristine Environment

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Persistent phylogeographic structure of an emerging virus on a homogeneous landscape

10.7287/peerj.preprints.27260v1 ◽

2018 ◽

Author(s):

Trieste Musial ◽

Scott Duke-Sylvester ◽

Rolan Davis ◽

Roman Biek ◽

Leslie A. Real

Keyword(s):

Genetic Structure ◽

Rabies Virus ◽

Animal Movement ◽

Landscape Heterogeneity ◽

Spatial Genetic Structure ◽

Molecular Data ◽

Landscape Composition ◽

Early Years ◽

Phylogeographic Structure ◽

Pathogen Populations

Landscape composition and structure influence animal movement, which in turn can affect transmission of their diseases. Spatio-temporal variation in host diffusion, caused by landscape heterogeneity, is thus expected to generate corresponding phylogeographic patterns in the pathogen. However, establishing causative links between genetic structure in pathogen populations and environmental variation does require appropriate null models. Here, we present an empirical example of the emergence and multi-decade persistence of phylogeographic structure on a homogeneous landscape in a rapidly diversifying pathogen in the absence of any apparent landscape heterogeneity. By applying phylogeographic inference to 173 sequences of a raccoon-specific strain of rabies virus, we reconstruct patterns of the virus’ evolution and diffusion on the Florida peninsula, USA, from its first emergence in the 1940’s to the present. Consistent with a lack of significant landscape heterogeneity relevant to raccoon movement in Florida, we found that the speed of rabies virus diffusion was spatially homogeneous across the peninsula. In contrast, we document the emergence of strong phylogeographic structure in the virus, in the form of five monophyletic lineages that diverged during the early years of colonization and now each occupy a distinct sub-region of Florida. Based on samples taken over multiple decades, we show that the spatial distribution of these lineages has changed little over the past four decades. This phylogeographic stability allowed us to retrospectively identify a small set of counties within Florida as the likely source of the virus strain that seeded a much larger rabies outbreak in the northeastern USA in the 1970s. Our results provide a rare empirical demonstration that spatial genetic structure can arise and be maintained in the absence of landscape heterogeneity, which has wider implications for the interpretation of phylogeographic data and the reconstruction of historical colonization patterns from molecular data.

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Effects of landscape heterogeneity on population genetic structure and demography of Amazonian phyllostomid bats

Mammal Research ◽

10.1007/s13364-020-00546-3 ◽

2020 ◽

Cited By ~ 1

Author(s):

Sofia Marques Silva ◽

Gilmax Ferreira ◽

Hanna Pamplona ◽

Tuane Letícia Carvalho ◽

Juliana Cordeiro ◽

...

Keyword(s):

Genetic Structure ◽

Population Genetic Structure ◽

Population Genetic ◽

Landscape Heterogeneity

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Rapid phenotypic change in a polymorphic salamander over 43 years

Scientific Reports ◽

10.1038/s41598-021-02124-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maggie M. Hantak ◽

Nicholas A. Federico ◽

David C. Blackburn ◽

Robert P. Guralnick

Keyword(s):

Climate Change ◽

Body Size ◽

Morphological Changes ◽

Phenotypic Change ◽

Color Morph ◽

Museum Specimens ◽

Linear Modeling ◽

Modeling Framework ◽

Color Morphs ◽

Morph Frequency

AbstractColor polymorphic animals offer a unique system for studying intraspecific phenotypic responses to climate change. Discrete color morphs are easy to identify, and correlated trait responses of morphs can indicate how climate warming may facilitate long-term maintenance of polymorphisms. We use a historical dataset spanning 43 years to examine temporal shifts in color morph frequency and body size in response to climate in the Eastern Red-backed Salamander, Plethodon cinereus, which contains a widespread striped/unstriped color polymorphism. We created a pipeline to extract high-throughput trait data from fluid-preserved museum specimens where we batch-photographed salamanders, de-aggregated individual specimens from photographs, and solicited help of community scientists to score color morphs. We used a linear modeling framework that includes information about spatial population structure to demonstrate that color morph frequency and body size vary in response to climate, elevation, and over time, with an overall trend of higher frequency and decreased body size of the striped morph, but increased size of the unstriped morph. These surprising results suggest that morphs may be responding to multiple climate and geographic drivers through co-adapted morphological changes. This work highlights new practices of extracting trait data from museum specimens to demonstrate species phenotypes response to climate change.

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The genetic structure of a southern peripheral population of the snail Cepaea nemoralis

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1973.0023 ◽

1973 ◽

Vol 183 (1073) ◽

pp. 371-384 ◽

Cited By ~ 10

Keyword(s):

Genetic Structure ◽

Land Snail ◽

Species Range ◽

Peripheral Populations ◽

Colour Morph ◽

Peripheral Population ◽

Southern Limit ◽

Cepaea Nemoralis ◽

The North ◽

Morph Frequency

The polymorphic land snail Cepaea nemoralis reaches the southern limit of its range in Yugoslavia. The overall frequency of yellow shells is much higher than in Britain (95% compared to 54%), while the frequencies of the genes controlling the number of bands on the shell do not differ as greatly from those found in British populations. Pink shells are found most commonly in one area which is known to be a frost hollow. The frequencies of the various phenotypes shows a great deal of microgeographical variation which does not appear to be related to topography. The existence of an apparent selective response at the colour locus to gross climatic differences from the north to the south of the species’ range suggests that microclimate may be important in affecting local differentiations (‘area effects’) in shell colour morph frequency found in central populations. It is possible that the absence of such a selective response in the frequency of the banding genes in Yugoslav peripheral populations indicates that climatic selection is also less important in controlling their microgeographical differentiation.

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