DOI: 10.5061/dryad.h07s9d1
title: Data from: Golden orbweavers ignore biological rules: phylogenomic and comparative analyses unravel a complex evolution of sexual size dimorphism

description: Instances of sexual size dimorphism (SSD) provide the context for rigorous
 tests of biological rules of size evolution, such as Cope’s Rule (phyletic
 size increase), Rensch’s Rule (allometric patterns of male and female
 size), as well as male and female body size optima. In certain spider
 groups, such as the golden orbweavers (Nephilidae), extreme female-biased
 SSD (eSSD, female:male body length ≥ 2) is the norm. Nephilid genera
 construct webs of exaggerated proportions, which can be aerial,
 arboricolous, or intermediate (hybrid). First, we established the backbone
 phylogeny of Nephilidae using 367 Anchored Hybrid Enrichment (AHE)
 markers, then combined these data with classical markers for a reference
 species-level phylogeny. Second, we used the phylogeny to test Cope and
 Rensch’s Rules, sex specific size optima, and the coevolution of web size,
 type, and features with female and male body size and their ratio, SSD.
 Male, but not female, size increases significantly over time, and refutes
 Cope's Rule. Allometric analyses reject the converse, Rensch's
 Rule. Male and female body sizes are uncorrelated. Female size evolution
 is random, but males evolve towards an optimum size (3.2-4.9 mm). Overall,
 female body size correlates positively with absolute web size. However,
 intermediate sized females build the largest webs (of the hybrid type),
 giant female Nephila and Trichonephila build smaller webs (of the aerial
 type), and the smallest females build the smallest webs (of the
 arboricolous type). We propose taxonomic changes based on the criteria of
 clade age, monophyly and exclusivity, classification information content,
 and diagnosability. Spider families, as currently defined, tend to be
 between 37-98 million years old, and Nephilidae is estimated at 133 Ma (97
 - 146), thus deserving family status. We therefore resurrect the family
 Nephilidae Simon 1894 that contains Clitaetra Simon 1889, the Cretaceous
 Geratonephila Poinar & Buckley 2012, Herennia Thorell 1877,
 Indoetra Kuntner 2006, new rank, Nephila Leach 1815, Nephilengys L. Koch
 1872, Nephilingis Kuntner 2013, Palaeonephila Wunderlich 2004 from
 Tertiary Baltic amber, and Trichonephila Dahl 1911, new rank. We propose
 the new clade Orbipurae to contain Araneidae Clerck 1757, Phonognathidae
 Simon 1894, new rank, and Nephilidae. Nephilid female gigantism is a
 phylogenetically-ancient phenotype (over 100 Ma), as is eSSD, though their
 magnitudes vary by lineage.
description: TableS1Table S1. Average male and female body part sizes and the derived SSD indices used in comparative analyses. BL = body length; CW = carapace width; CL = carapace length; SSD = sexual size dimorphism as a female to male size ratio.TableS2Table S2. Female web characteristics for a subset of nephilids in Table S1. The mean ± standard deviation, calculated from field web measurements, were used in comparative analyses.TableS3Table S3. Data for deep reconstruction of sexual size dimorphism in Figure 6.Appendix S1Appendix S1. R codes and results of comparative analyses.Appendix_S1.docxFigure S1Figure S1. Anchored Hybrid Enrichment topologies from the analyses of the concatenated datasets.FigS1_CONCAT_trees.pdfFigure S2Figure S2. Anchored Hybrid Enrichment species tree topologies.FigS2_ASTRAL_trees.pdfFigure S3Figure S3. Maximum Likelihood inference of concatenated data from 367 loci (“loose” dataset). NEP = Nephilidae (shaded area), ARA = Araneidae, PHO = Phonognathidae, TET = Tetragnathidae, MIM = Mimetidae.FigS3.jpgFigure S4Figure S4. Species-level phylogeny of Nephilidae: Concatenated phylogeny constrained for Anchored Hybrid Enrichment topology with node supports.FigS4.jpgFigure S5Figure S5. Macroevolutionary patterns of nephilid size evolution. Reconstructed ancestral states are plotted over phyletic time (given as cladogenetic events on phylogeny). Male, but not female size, exhibits a significant phyletic increase, and sexual size dimorphism stagnates.FigS5.jpgFigS6Figure S6. The evolution of body size and sexual size dimorphism (SSD) in nephilid spiders: an alternative optimization to Fig. 4. (a) Female body length shows 26 increases (+) and 28 decreases (-); (b) Male body length has 24 increases and 30 decreases; (c) SSD shows 24 increases and 30 decreases. An ultrametric tree was pruned to contain the 28 taxa with known size variation in both sexes. Sizes and SSD (ratio female/male body length) were optimized on the tree using square change parsimony in Mesquite. Clades are color coded by web type in (a).Figure S7Figure S7. The evolution of sexual size dimorphism (SSD, as simple female to male body size ratio) on a genus level phylogeny, an alternative to Fig. 6. The genus level topology is from AHE analyses, the SSD ratios are optimizations for each nephilid genus (Fig. S6c) or exemplar SSD data for outgroups (Table S3). The reconstruction is linear parsimony in Mesquite. Inset image shows Trichonephila clavipes female (left) and male (right). The sizes of female and male symbols correspond to relative total body lengths (Table S3).FigS7.jpgPhylogenetic Supplementary MaterialSee readme file.