Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica

PeerJ, Год журнала: 2016, Номер 4, С. e2696 - e2696

Опубликована: Ноя. 16, 2016

Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in Neotropics. Tree ferns among conspicuous elements these restricted to regions which minimum temperatures rarely drop below freezing rainfall is high evenly distributed around year. Current phylogeographic data suggest that some forest-adapted species remained situ expanded lowlands during glacial cycles contracted allopatrically interglacials. Although observed genetic signals population size changes including tree correspond predicted Pleistocene climate change dynamics, patterns intraspecific lineage divergence showed temporal incongruence. Methods Here we combined phylogenetic analyses, ancestral area reconstruction, time estimates with climatic altitudinal (environmental space) for phenotypic traits fern make inferences about evolutionary processes deep time. We used Bayesian inference geographic distribution investigate elevation environmental preferences Mesoamerican ferns. The phylogeny was then estimate times ask whether shifts were linked events historical preferences. Results trees retrieved Cyathea, Alsophyla, Gymnosphaera Sphaeropteris monophyletic clades. Splits genera found forests recent, from Neogene Quaternary, Australia identified as clades genera, except Mesoamerica. Climate tolerance not divergent hypothesized ancestors significant variables elevation. For elevational shifts, repeated low elevations. Conclusions Our representatives Cyatheaceae main lineages migrated different have persisted environmentally unstable areas but extant diverged recentrly their ancestors.

Язык: Английский

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In and out of refugia: historical patterns of diversity and demography in the North American Caesar's mushroom species complex

Molecular Ecology, Год журнала: 2015, Номер 24(23), С. 5938 - 5956

Опубликована: Окт. 14, 2015

Abstract Some of the effects past climate dynamics on plant and animal diversity make‐up have been relatively well studied, but to less extent in fungi. Pleistocene refugia are thought harbour high biological (i.e. phylogenetic lineages genetic diversity), mainly as a product increased reproductive isolation allele conservation. In addition, extinction rates erosion expected previously glaciated regions. consequences might involve changes range population size that can result divergence incipient or cryptic speciation. Many these dynamic processes patterns be inferred through coalescent methods. this study, we first delimit species within group closely related edible ectomycorrhizal Amanita from North America (the American Caesar's mushrooms complex) using multilocus coalescent‐based approaches; then address questions change genetics group. Our study includes extensive geographical sampling throughout distribution range, DNA sequences three nuclear protein‐coding genes. Results reveal speciation refugia. Population sizes expansions seem larger at midrange latitudes (Mexican highlands SE USA ). Range shifts proportional expansions, which were overall more common during Pleistocene. This documents responses fungi also highlights applicability multispecies comparative phylogeographical analyses assessments include ancestral species.

Язык: Английский

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Biogeography and evolution of Central American cloud forest salamanders (Caudata: Plethodontidae:Cryptotriton), with the description of a new species

Zoological Journal of the Linnean Society, Год журнала: 2015, Номер 175(1), С. 150 - 166

Опубликована: Авг. 18, 2015

The cloud forests of Mesoamerica are notable for their high endemism, and plethodontid salamanders provide a striking example divergence microendemism across forest blocks at regional level. Salamanders that make use arboreal bromeliad microhabitats in the appear to be especially prone driven by natural habitat fragmentation, expected show endemism small spatial scales. We multilocus dataset investigate biogeographic history relationships among species genus salamander, Cryptotriton, restricted Nuclear Central America. morphological data set along with coalescent delimitation method reveal presence least one undescribed from an isolated eastern Guatemala. Biogeographic analyses Cryptotriton has different than another clade forest-restricted same region, perhaps indicating each expansion diversification other through preemptive occupancy. Our results suggest isolation relatively short geographic distances led range fragmentation deep between species. Exploration remaining patches likely will continue undetected diversity.

Язык: Английский

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Bidirectional anatomical effects in a mistletoe–host relationship: Psittacanthus schiedeanus mistletoe and its hosts Liquidambar styraciflua and Quercus germana

American Journal of Botany, Год журнала: 2016, Номер 103(6), С. 986 - 997

Опубликована: Июнь 1, 2016

PREMISE OF THE STUDY: During the interactions between a parasitic plant and its host, parasite affects host morphologically, anatomically, physiologically, yet there has been little focus on effect of hosts parasite. Here, functional hemiparasitic mistletoe Psittacanthus schiedeanus Liquidambar styraciflua Quercus germana were interpreted based anatomical features vascular tissues. METHODS: Using standard techniques for light transmission electron microscopy, we studied effects P. phloem anatomy vice versa. KEY RESULTS: The larger sieve elements, companion cells, plate areas when it is parasitizing L. than Q. ; however, produces systemic hosts, reducing size in but increasing . Those seem to be bidirectional effects. No direct connections secondary that observed. Parenchymatic cells contact with connective parenchyma develop half‐plasmodesmata, while those do not. CONCLUSIONS: comprise modifications are potentially affected by phenology combination hormonal agents such as auxins, symplasmic or apoplasmic pathway solutes import.

Язык: Английский

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Ecological Speciation in Nolina parviflora (Asparagaceae): Lacking Spatial Connectivity along of the Trans-Mexican Volcanic Belt

PLoS ONE, Год журнала: 2014, Номер 9(6), С. e98754 - e98754

Опубликована: Июнь 6, 2014

The hypothesis of ecological speciation states that as populations diverge in different niches, reproductive isolation evolves a by-product adaptation to these environments. In this context, we used Nolina parviflora model test if species evolved via and explore current historical gene flow among its populations. is montane endemic Mexico with geographical distribution restricted largely the Trans-Mexican Volcanic Belt. This mountain range one most complex geological regions Mexico, having undergone volcanism from mid-Miocene present. Ecologically, Belt possesses types vegetation, including tropical dry forest; oak, pine, pine-oak, pine-juniper forests; xerophytic scrub - all which maintain N. parviflora. Using models, climatic analyses, spatial connectivity morphological comparisons, found significant differences variables between two distinct (east vs. west). could mean geographically isolated diverged another niche divergence, indicating speciation. Spatial analysis revealed no under present or last glacial maximum climate lack regions. results imply may encompass more than single species.

Язык: Английский

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