Effects of native pollinator specialization, self-compatibility and flowering
duration of European plant species on their invasiveness elsewhere
Thomas Chrobock, Christiane N. Weiner, Michael Werner, Nico Blüthgen, Markus Fischer
and Mark van Kleunen
Supporting Information
Appendix S2
CONSTRUCTION OF THE PHYLOGENY OF THE 118 EUROPEAN GRASSLAND
SPECIES
We constructed a phylogenetic tree of our 118 study species (Fig. S2) by pruning the
recently published DaPhnE supertree for the European flora (Durka & Michalski 2012). The
complete DaPhne tree includes 4685 species, and 1103 of its internal nodes have been
dated (Durka & Michalski 2012). The phylogeny of the Angiosperm Phylogeny Group III is
used as backbone for the families, and subtrees from 518 molecular studies were manually
added, if possible, using multi-gene consensus trees (Durka & Michalski 2012). This is the
best phylogenetic tree available for the European plant species, but we cannot exclude the
possibility that there are mistakes in the topology.
Because we analyzed our data set containing 463 species-by-country combinations
by applying phylogenetically informed linear mixed effects models, we had to adjust the tree
in the following way. For each species that occurred in more than one region, we integrated a
new node into the tree leading to multiple tips, each corresponding to one of the non-native
regions in which the species occurred. This tree thus had 463 instead 118 tips. We adjusted
the within-species branch lengths to the equivalent of 100 years. The appropriateness of the
chosen within-species branch length is open to argument, and could bias the results.
However, we think that 100 years is small enough a time period to ensure phylogenetic
equality between those tips (Felsenstein 2008; Dawson et al. 2012). Moreover, 100 years
1
corresponds more or less to the period of time that many of the different naturalized
populations of a species have been separated from the native populations and from
naturalized populations in other regions of the world.
2
Fig. S2. Phylogenetic tree of the 118 European grassland species analyzed in this study.
3
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Durka, W. & Michalski, S.G. (2012) DaPhnE - a dated phylogeny of a large European flora
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Felsenstein, J. (2008) Comparative methods with sampling error and within-species
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4