Celia Hein's First Authored Paper
Celia Hein (PhD Student) from Wagner Lab published her 1st authored paper Can We Compare Effect Size of Spatial Genetic Structure Between Studies and Species Using Moran Eigenvector Maps? in Frontiers in Ecology & Evolution.
https://doi.org/10.3389/fevo.2021.612718
The field of landscape genetics is still quite young, however, it is progressing toward comparative, multispecies empirical studies and meta-analysis. An important first step towards this goal is to learn how best to compare the strength of spatial genetic structure between studies and species. Moran's Eigenvector Maps (MEM) are a promising method because they model spatial structure of any type, including structure resulting from multiple processes, which is typical of empirical landscapes. Using MEM we can quantify spatial genetic structure in two ways: an adjusted R-square (as generated by MEMgene) and Moran's I. Specifically, we focused on three factors that nearly always vary between empirical studies and species: underlaying population demography, genetic resolution, and spatial sampling design. If the measures of effect size are robust to variation in these factors, then Moran's Eigenvector Maps may be a promising method to investigate further for meta-analysis and multispecies studies. To test this, we used simulated, published datasets on a quasi-continuous, square landscape under four demographic scenarios (island model, isolation-by-distance, expansion from one or two refugia). We also varied the genetic resolution and the spatial sampling design. Then we compared our measures of effect size between scenarios and found that both measures of effect size were highly sensitive to the number of spatial locations and the number of individuals sampled per location, but not to the number of loci. Also, the bias is not consistent between different demographic scenarios. We conclude that more robust measures of effect size need to be developed before the strength of spatial genetic structure can be accurately compared.