Adaptive diversification is thought to be shaped by ecological opportunity. A prediction of this ecological process of diversification is that it should result in congruent bursts of lineage and phenotypic diversification, but few studies have found this expected association. Here, we study the relationship between rates of lineage diversification and body size evolution in the turtle ants, a diverse Neotropical clade. Using a near complete, time-calibrated phylogeny we investigated lineage diversification dynamics and body size disparity through model fitting analyses and estimation of per-lineage rates of cladogenesis and phenotypic evolution. We identify an exceptionally high degree of congruence between the high rates of lineage and body size diversification in a young clade undergoing renewed diversification in the ecologically distinct Chacoan biogeographical region of South America. It is likely that the region presented turtle ants with novel ecological opportunity, which facilitated a nested burst of diversification and phenotypic evolution within the group. Our results provide a compelling quantitative example of tight congruence between rates of lineage and phenotypic diversification, meeting the key predicted pattern of adaptive diversification shaped by ecological opportunity.
Body length data (log transformed) in Cephalotes
Maximum reported body length measurements from the worker caste of Cephalotes species. Data are log transformed. Data are from multiple museum collections, most of which are in de Andrade and Baroni-Urbani (1999). Data for C. specularis are from Brandão et al. (2014), measurements for C_sp3 came from data from a reproductively mature colony (S. Powell, in press), and data for C_sp2 came from one individual (S. Powell, unpublished data).
Ceph_bodylength.txt
Molecular and morphological data matrix with MrBayes block
Nexus file that includes the sequence alignment of 5 genes (from Price et al. 2014) and a morphological dataset (from de Andrade and Baroni-Urbani 1999). About 50% of species have molecular data, and morphological data are included for all known Cephalotes species, including extinct species. A MrBayes blocks is included for the analyses for Figure S1 (extinct and extant species phylogram) and Figure S2 (extant species phylogram).
Ceph_phylogram.nex
Nexus file for divergence time estimation (node-calibrated and tip-dated)
Nexus file used for divergence time estimation analyses. It includes molecular data from Price et al. (2014) and morphological data from de Andrade and Baroni-Urbani (1999). MrBayes blocks are included for total evidence tip-dating (Figure S3)and node-calibration (Figure S4) analyses.
Ceph_time_calibration.nex
BAMM control file for lineage diversification
This is the input file (called the control file) for lineage diversification analysis in BAMM. The file was directly adapted from the documentation on the BAMM website (http://bamm-project.org/).
lineage_controlfile.txt
BAMM control file for trait evolution
This is the input file (called the control file) for analysis of trait evolution in BAMM. The file was directly adapted from the documentation on the BAMM website (http://bamm-project.org/).
trait_controlfile.txt
BAMMtools R script for lineage diversification
Script used in the R program BAMMtools for the analysis and visualization of lineage diversification results in BAMM. The script was adapted from documentation on the BAMM website (http://bamm-project.org/).
BAMMtools_lineage_script.R
BAMMtools R script for trait evolution
Script used in the R program BAMMtools for the analysis and visualization of trait evolution, specifically body size evolution, results in BAMM. The script was adapted from documentation on the BAMM website (http://bamm-project.org/).
BAMMtools_trait_script.R
R script for gamma and MCCR analyses
Script for conducting gamma/MCCR analyses in Laser in R.
gamma_MCCR.R
R script for DDD analyses
R script for performing DDD analyses on the phylogeny. It does the likelihood optimization from two different sets of starting values of the parameters, for the most parameter-rich models.
MLkeyinnCephalotes.R
R script for DDD settings
The R script loads the turtle ant data and calls the function MLkeyinnCephalotes to perform the DDD analyses. It provides all the settings which are then passed to this function.
MLkeyinnCephalotes2.R
Node-calibrated MCC tree
Node-calibrated maximum clade credibility (MCC) tree for Cephalotes.
Cephalotes_node_calibration.tre
Tip-dated MCC tree
Tip-dated maximum clade credibility (MCC) tree for Cephalotes.
Cephalotes_tip_dating.tre