Data from: Evolutionary diversity in tropical tree communities peaks at intermediate precipitation

Global patterns of species and evolutionary diversity in plants are primarily determined by a temperature gradient, but precipitation gradients may be more important within the tropics, where plant species richness is positively associated with the amount of rainfall. The impact of precipitation on the distribution of evolutionary diversity, however, is largely unexplored. Here we detail how evolutionary diversity varies along precipitation gradients by bringing together a comprehensive database on the composition of angiosperm tree communities across lowland tropical South America (2,025 inventories from wet to arid biomes), and a new, large-scale phylogenetic hypothesis for the genera that occur in these ecosystems. We find a marked reduction in the evolutionary diversity of communities at low precipitation. However, unlike species richness, evolutionary diversity does not continually increase with rainfall. Rather, our results show that the greatest evolutionary diversity is found in intermediate precipitation regimes, and that there is a decline in evolutionary diversity above 1,490 mm of mean annual rainfall. If conservation is to prioritise evolutionary diversity, areas of intermediate precipitation that are found in the South American ‘arc of deforestation’, but which have been neglected in the design of protected area networks in the tropics, merit increased conservation attention.


Genus_phylogeny.tre - Time-calibrated molecular phylogeny of 1,100 angiosperm genera found in lowland tree communities of tropical South America. Phylogenetic reconstruction based on sequences of rbcL and matK plastid regions from plants collected during fieldwork or available in GenBank. Tree topology and divergence times of taxa were estimated using a Bayesian Markov Chain Monte Carlo approach. Branch lengths were time-scaled using a relaxed molecular clock with fossil-based age constraints implemented on nodes.

Genus_multiphylogeny.tre - Set of 100 time-calibrated molecular phylogenies from a Bayesian Markov Chain Monte Carlo (MCMC) posterior distribution. Each phylogeny comprises 1,100 angiosperm genera found in lowland tree communities of tropical South America. Phylogenetic reconstruction based on sequences of rbcL and matK plastid regions from plants collected during fieldwork or available in GenBank. Tree topology and divergence times of taxa were estimated using a Bayesian MCMC approach. Branch lengths were time-scaled using a relaxed molecular clock with fossil-based age constraints implemented on nodes.

Species_phylogeny.tre - Phylogeny of angiosperm species found in lowland tree communities of tropical South America, generated using the genus-level phylogeny as a basis (see Genus_phylogeny.tree above). This consisted of pruning the genus-level phylogeny to 852 genera in the community dataset (http://www.neotroptree.info/), and then imputing all 8,174 species in this dataset by simulating a random birth-death phylogeny for each genus, using a speciation rate of 1 and an extinction rate of 0.9.

Appendix 3.xlsx - List of 1,100 angiosperm genera used in the phylogenetic reconstructions, their respective sources of rbcL and matK sequences, GenBank accession numbers, eDNA numbers (i.e., internal codes for sequences generated at the Royal Botanic Garden Edinburgh), collectors, collector numbers and herbaria where vouchers were deposited (when applicable). RBG = Royal Botanic Garden Edinburgh. Asterisk indicates the 852 genera used in the community phylogenetic analyses.

Neves, Danilo M.; Dexter, Kyle G.; Baker, Timothy R. et al. (2020). Data from: Evolutionary diversity in tropical tree communities peaks at intermediate precipitation [Dataset]. Dryad. https://doi.org/10.5061/dryad.gf1vhhmk0