| Autor: |
George P. Tiley, Andrew A. Crowl, Tchana O. M. Almary, W. R. Quentin Luke, Cédrique L. Solofondranohatra, Guillaume Besnard, Caroline E.R. Lehmann, Anne D. Yoder, Maria S. Vorontsova |
| Rok vydání: |
2023 |
| Popis: |
Summary1) Research Aims — The extent of Madagascar’s grasslands prior to human colonization is unresolved. We used population genetic analyses of a broadly dominant C4fire-adapted grass,Loudetia simplex, as a proxy for estimating grassland change through time. In the absence of population genomic resources, we used target-enrichment data. We carefully examined the utility of these data for population genetics to make recommendations on cost-effective strategies for conservation genetics. We explored the potential of estimating individual ploidy levels from target-enrichment data and how assumptions about ploidy could affect analyses.2) Methods — We developed a novel bioinformatic pipeline based to estimate ploidy and genotypes from target-enrichment data. We estimated standard population genetic summary statistics in addition to species trees and population structure. Extended Bayesian skyline plots provided estimates of population size through time for empirical and simulated data.3) Key Result — All MalagasyLoudetia simplexindividuals sampled in this study formed a clade and possibly indicated an ancestral high-altitude distribution near the present-day Itremo protected area. Demographic models suggested grassland expansions occurred prior to the Last Interglacial Period and supported extensive grasslands prior to human colonization. Though there are limitations to target-enrichment data for population genetic studies, we find that analyses of population structure are reliable.4) Key Point —Genetic variation inLoudetia simplexsupports widespread grasslands in Madagascar prior to the more recent periods of notable paleoclimatic change. However, the methods explored here could not differentiate between paleoclimatic change near the Last Glacial Maximum and anthropogenic effects. Target-enrichment data can be a valuable tool for analyses of population structure in the absence of reference genomic resources. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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