In this talk I will describe some recent advances in the spatial analysis of phylodiversity, and demonstrate its calculation and visualisation using the Biodiverse software.  In its simplest sense, spatial phylogenetics involves mapping the branches of phylogenetic trees across a region and then analysing that distribution to derive indices of phylogenetic variation for each location.  For example, the sum of branch lengths in a location is the phylogenetic diversity (PD) as defined by Faith.  By differentially weighting the contribution of branches one can gain further insights into the diversity across a region, and potential causes.  For example, by giving higher weight to range restricted lineages one can identify regions where geographically rare lineages are concentrated, whether such lineages represent old or new diversity (i.e. palaeo- or neo-endemism), and also which branches on the tree are driving the observed patterns.  Further, one can use phylogenetic turnover metrics to assess how much of a phylogenetic tree is shared between two or more locations.  If one is interested in understanding regions of endemism then one can use recently developed range-weighted metrics to reduce the influence of widespread lineages.  One of the advantages of using Biodiverse for spatial phylogenetics is that it supports interactive visualisation of analysis results in both geographic and phylogenetic spaces.  This makes it a simple process to identify how the tree is distributed across a landscape, and how parts of a landscape are distributed across the tree, potentially leading to more informed hypothesis generation.

Biography

Shawn Laffan’s research interests are in spatial analysis and geocomputation, with patterns of biodiversity being a key focus.  An important research output is free and open source tools for spatial analysis, for example Biodiverse (http://purl.org/biodiverse).  He is Associate Professor in the School of Biological, Earth and Environmental Sciences at UNSW, and Asia-Pacific Editor for the International Journal of Geographical Information Science.

Key links and publications

Biodiverse software:  http://purl.org/biodiverse

Spatial phylogenetics:  http://ucjeps.berkeley.edu/bryolab/CPPP/spatial.html

González-Orozco, C.E., Pollock, L.J., Knerr, N., Mishler, B.D., Miller, J.T., Laffan, S.W., Thornhill, A.H., Rosauer, D.F., Faith, D., Nipperess, D., Kujala, H., Linke, S. and Gruber, B. (in press) Phylogenetic approaches uncover biodiversity threats under climate change. Nature Climate Change, doi: 10.1038/nclimate3126.

Laffan, S.W., Rosauer, D.F., Di Virgilio, G., Miller, J.T., Gonzales-Orozco, C., Knerr, N., Thornhill, A. & Mishler, B.D. (2016) Range-weighted metrics of species and phylogenetic turnover can better resolve biogeographic breaks and boundaries. Methods in Ecology and Evolution, 7, 580-588.

Laffan, S.W., Lubarsky, E. & Rosauer, D.F. (2010) Biodiverse, a tool for the spatial analysis of biological and related diversity. Ecography. Vol 33, 643-647.

Mishler, B.D., Knerr, N., González-Orozco, C.E., Thornhill, A.H., Laffan, S.W. & Miller, J.T. (2014) Phylogenetic measures of biodiversity and neo- and paleo-endemism in Australian Acacia. Nature Communications, 5, 4473.

Thornhill, A.H., Mishler, B.D., Knerr, N., González-Orozco, C.E., Costion, C., Crayn, D., Laffan, S.W. & Miller, J.T. (2016) Continental scale phylogenetic diversity and endemism in Australian angiosperms Journal of Biogeography, 43, 2085–2098.

Rosauer, D.F., Laffan, S.W., Crisp, M.D., Donnellan, S.C. & Cook, L.G. (2009) Phylogenetic endemism: a new approach to identifying geographical concentrations of evolutionary history. Molecular Ecology, 18, 4061-4072.

Evolution, Ecology and Genetics Seminar Series