DOI: 10.5061/dryad.bj82r
title: Data from: Sweet tetra-trophic interactions: multiple evolution of nectar secretion, a defensive extended phenotype in cynipid gall wasps

description: Many herbivores employ reward-based mutualisms with ants to gain
 protection from natural enemies. We examine the evolutionary dynamics of a
 tetra-trophic interaction in which gall wasp herbivores induce their host
 oaks to produce nectar-secreting galls, which attract ants that provide
 protection from parasitoids. We show that, consistent with other gall
 defensive traits, nectar secretion has evolved repeatedly across the oak
 gall wasp tribe and also within a single genus (Disholcaspis) that
 includes many nectar-inducing species. Once evolved, nectar secretion is
 never lost in Disholcaspis, consistent with high defensive value of this
 trait. We also show that evolution of nectar secretion is correlated with
 a transition from solitary to aggregated oviposition, resulting in
 clustered nectar-secreting galls, which produce a resource that ants can
 more easily monopolize. Such clustering is commonly seen in ant guard
 mutualisms. We suggest that correlated evolution between maternal
 oviposition and larval nectar induction traits has enhanced the
 effectiveness of this gall defense strategy.
description: Cynipid species inducing
 nectar-secreting gallsCynipid species inducing
 galls known to secrete nectar, with information on their galls. Data
 collected from the literature and personal field
 observations.Online Supplementary Table
 S1.xlsSpecimen collection and
 sequencing details, including GenBank accession numbers.Specimen collection and
 sequencing details, including GenBank accession numbers. Species names in
 bold are nectar secretors; individual codes in italics indicate
 Disholcaspis species included in the Cynipini-wide analyses. Four species
 currently classified as belonging to the genus Disholcaspis (D.
 chrysolepidis, D. corallina, D. plumbella and D. sulcata) were excluded
 from the Disholcaspis study as sequence data (see Figure 2) and morphology
 (see Melika and Abrahamson 2002) both indicate they are not true
 Disholcaspis.Online Supplementary Table
 S2.xlsPosterior probabilities
 of nectar secretion or no nectar secretion at ancestral nodes within the
 Disholcaspis phylogeny.Posterior probabilities
 of nectar secretion or no nectar secretion at ancestral nodes within the
 Disholcaspis phylogeny (nodes numbered in insert). Posterior probabilities
 of ancestral character states are presented for the full set of models
 visited in the rjMCMC run (columns 2 & 3), those under a symmetric
 reversible model (columns 4 & 5) and under a model where the rate of
 change of nectar to no nectar was fixed at zero (columns 6 & 7). The
 final set of columns indicate likelihoods of models run with the
 respective node fixed to one or other character state, and the result of a
 Bayes factor test comparing the two models.Online Supplementary Table
 S3.xlsCynipini cytb
 sequencesAlignment of Cynipini
 cytochrome b sequencesCynipini_cytb.nexCynipini D2 sequencesAlignment of Cynipini 28S D2 sequencesCynipini_D2.nexCynipini opsin sequencesAlignment of Cynipini opsin sequencesCynipini_opsin.nexDisholcaspis cytb sequencesAlignment of Disholcaspis cytochrome b sequencesDisholcaspis_cytb.nexDisholcaspis D2 sequencesAlignment of Disholcaspis 28S D2 sequencesDisholcaspis_D2.nexDisholcaspis ITS2 sequencesAlignment of Disholcaspis internal transcribed spacer 2 sequencesDisholcaspis_ITS2.nexDisholcaspis opsin sequencesAlignment of Disholcaspis opsin sequencesDisholcaspis_opsin.nex