Ecological Archives E096-037-A4

Paul J. CaraDonna, David W. Inouye. 2015. Phenological responses to climate change do not exhibit phylogenetic signal in a subalpine plant community. Ecology 96:355–361. http://dx.doi.org/10.1890/14-1536.1

Appendix D. Sensitivity test of phylogenetic signal results.

Table D1. To test the robustness of our results to variation in branch length and topology, we compared our results from the molecular genus tree (Table 1; Supplement) to those generated from a less well-resolved phylogeny (Wikström et al. 2001, following Davies et al. 2013); the two phylogenies differ in branch lengths and topology above the genus level. Values reported in this table are from phylogenetic signal tests from the less well-resolved phylogeny (Wikström et al. 2001). Overall, phylogenetic signal results were qualitatively similar across the two different phylogenetic trees, indicating that our results on the molecular tree are robust to variation in branch length and topology.  In general, the strength and significance of phylogenetic patterns was similar, especially using Blomberg's K.  However, we note that results for Pagel's λ for flowering time were somewhat sensitive, but this is not surprising, and is expected to some degree. Pagel's λ tends to be a more conservative test (Münkemüller et al. 2012), and the results presented here are generated from a phylogeny where branch length and topology estimates are less reliable as compared to the molecular tree. Thus, because the results of Pagel's λ are qualitatively similar across both trees, we argue they are reasonably robust to variation in phylogenetic branch length and topology.

Phenological trait

Blomberg's K

P

Pagel's λ

P

Mean flowering time (1974–1984)

first

0.470

0.042

   0.181

0.267

peak

0.518

0.020

   0.285

0.107

last

0.470

0.049

< 0.001

0.999

duration

0.461

0.167

< 0.001

0.999

Mean flowering time (1974–2012)

first

0.479

0.028

   0.222

0.221

peak

0.529

0.011

   0.310

0.086

last

0.543

0.023

   0.279

0.117

duration

0.469

0.171

< 0.001

0.999

Shift through time

first

0.362

0.437

< 0.001

0.999

peak

0.309

0.897

< 0.001

0.999

last

0.366

0.487

< 0.001

0.999

duration

0.363

0.539

< 0.001

0.999

Snowmelt sensitivity

first

0.403

0.215

  0.106

0.586

peak

0.289

0.945

< 0.001

0.999

last

0.449

0.069

< 0.001

0.999

duration

0.443

0.056

< 0.001

0.999

Temperature sensitivity

first

0.329

0.719

< 0.001

0.999

peak

0.291

0.916

< 0.001

0.999

last

0.399

0.201

< 0.001

0.999

duration

0.372

0.383

< 0.001

0.999

Literature cited

Davies, T. J., et al. 2013. Phylogenetic conservatism in plant phenology. Journal of Ecology 101:1520–1530.

Münkemüller, T., et al. 2012. How to measure and test phylogenetic signal. Methods in Ecology and Evolution 3:743–756.

Wikström, N., V. Savolainen, M. W. Chase. 2001. Evolution of the angiosperms: calibrating the family tree. Proceedings of the Royal Society B 268:2211–2220.


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