DOI: 10.5061/dryad.n7871
title: Data from: Evolution of extrafloral nectaries: adaptive process and selective regime changes from forest to savanna.

description: Much effort has been devoted to understanding the function of extrafloral
 nectaries (EFNs) for ant-plant-herbivore interactions. However, the
 pattern of evolution of such structures throughout the history of plant
 lineages remains unexplored. In this study, we used the hypothesis of
 plant defense mediated by ants as a theoretical framework to test more
 specific hypotheses about the adaptive role of EFNs during plant
 evolution. Emphasis was given to different processes (neutral or adaptive)
 and factors (habitat change and tradeoffs with new trichomes) that may
 have affected the evolution of ant-plant associations. We measured 7 EFN
 quantitative traits in all 105 species included in a well-supported
 phylogeny of the tribe Bignonieae (Bignoniaceae), and collected field data
 on ant-EFN interactions in 32 species. We identified a positive
 association between ant visitation (a surrogate of ant guarding) and the
 abundance of EFNs in vegetative plant parts, and rejected the hypothesis
 of phylogenetic conservatism of EFNs, with most traits presenting K-values
 &lt; 1. Modeling the evolution of EFN traits using maximum likelihood
 approaches further suggested adaptive evolution, with static-optimum
 models showing a better fit than purely drift models. Finally, the
 abundance of EFNs was associated to habitat shifts (with a decrease in the
 abundance of EFNs from forest to savannas), and a potential trade-off
 between the abundance of EFNs and estipitate glandular trichomes
 (trichomes with sticky secretion) was detected. These evolutionary
 associations appeared as evidence of divergent selection between species,
 and could also explain K-values &lt; 1. Overall, our results suggest
 that the evolution of EFNs was likely associated with adaptive processes.
 Experimental studies with multiple lineages, including savanna and forest
 species, could improve our understanding of the functional role of
 nectaries on plants.
description: 1_efns_ants1_patristic_distanceMETADATA associated with file "1_patristic_distance.xls": 1) Matrix representing the phylogenetic distance among species (patristic distance) based on the phylogeny file: "1_tree_20spp.nex". 2) Patristic distances were calculated using the function 'distTips' in the R package 'adephylo' (Pavoine et al. 2008*). *Pavoine, S.; Ollier, S.; Pontier, D. & Chessel, D. (2008) Testing for phylogenetic signal in life history variable: Abouheif's test revisited. Theoretical Population Biology: 73, 79-91.1_tree_20sppMETADATA associated with the phylogeny file "1_tree_20spp.nex": Phylogenetic tree used to calculate the phylogenetic distance among 20 plant species (patristic distance).2&3_EFNs_and_PCA_Bignonieae_species2&3_tree_100sppMETADATA associated with the phylogenetic file "2&3_tree_100spp.nex": Phylogenetic tree used to: 1) calculate/test phylogenetic signal (test K of Blomberg); 2) model the evolution of traits using Brownian model and O-U process with a single adaptive optimum; 3) test the association between habitat, trichomes and EFN variation.4_tree_105spp_EFNclustersMETADATA associated with phylogenetic file "4_tree_105spp_EFNclusters.nex": Phylogenetic tree with 105 spp. of the tribe Bignonieae, and the discrete data of EFN clusters (binary) on different vegetative plant parts (used to construct Fig.4 and Appendix S3). Five phylogenies are available in the file showing the alternative scenarios for the evolution of the tribe Bignonieae. Tree 1 was the topology used in all analyses. The data matrix includes four binary characters: Character 1 (EFN.Ab_ba)* = Presence or absence of EFN clusters on the base of the abaxial side of leaflets Character 2 (EFN.proph)* = Presence or absence of EFN clusters on the prophylls of the axillary buds Character 3 (EFN.stem)* = Presence or absence of EFN clusters on the interpetiolar region of stems *1 represents more than five EFNs in a single location (a cluster of EFNs), and 0 represents five or less EFNs.