Historical warming consistently decreased size, dispersal and speciation rate of fish

There is ongoing debate as to whether fish body size will decrease with global warming and how these changes may impact dispersal ability and speciation rate. Theory predicts that, under warmer temperatures, fish grow to a smaller size, undergo a reduction in dispersal ability and increase speciation rates. However, evaluations of such predictions are hampered owing to the lack of empirical data spanning both wide temporal and geographical scales. Here, using phylogenetic methods, we show that smaller clupeiform fish (anchovies and herrings) occurred historically in warmer waters, moved the shortest distances at low speed and displayed the lowest speciation rates. Furthermore, fish moved faster and evolved rapidly under higher rates of temperature change but these historical rates are far lower than current warming rates. Our results predict a future where smaller clupeiform fish that have reduced ability to move will be more prevalent; this, in turn, may reduce future speciation

Historical dynamics and current environmental effects explain the spatial distribution of species richness patterns of New World monkeys

Background Why biodiversity is not uniformly distributed on the Earth is a major research question of biogeography. One of the most striking patterns of disparity in species distribution are the biodiversity hotspots, which generally do not fit with the distribution of relevant components of the Neotropical biota. In this study, we assess the proximal causes of the species-richness pattern of one of the most conspicuous groups of Neotropical mammals, the New World monkeys the Platyrrhini. We test two complementary hypotheses: (1) there is a historical source-sink dynamic (addressed using macroevolutionary and macroecological approaches); (2) the large number of species in the Amazon basin is due to the constraints imposed by environmental variables occurring outside this area. Methods We first characterize spatial patterns of species richness and biodiversity hotspots using a new, objective protocol based on probabilities. Then we evaluate the source-sink hypothesis using BioGeoBEARS analysis and nestedness analysis of species richness patterns. Complementarily, to measure how often different species pairs appear in the same sites, we used null models to estimate the checkerboard score index (C-score). Finally, we evaluate the relationship between several climatic variables and species richness through ordinary least squares (OLS) and spatial autoregressive (SAR) models, and the potential environmental constraints on the pattern. Results We found one significant cluster of high values for species richness in the Amazon basin. Most dispersal events occurred from the Amazonian subregion to other Neotropical areas. Temperature (T), discrepancy (BR), and NODF indexes show a significant nesting in the matrix ordered by species richness and available energy. The C-score observed was significantly smaller than the null expectation for all sites in the Neotropics where there are records of platyrrhine species. Ten climatic variables comprised the best-fitting model that explains species richness. OLS and SAR models show that this set of variables explains 69.9% and 64.2% of species richness, respectively. Potential of evapotranspiration is the most important variable within this model, showing a linear positive relationship with species richness, and clear lower and upper limits to the species richness distribution. Discussion We suggest that New World monkeys historically migrated from their biodiversity hotspot (energetically optimal areas for most platyrrine species) to adjacent, energetically suboptimal areas, and that the different dispersal abilities of these species, the lack of competitive interactions at a macroecological scale, and environmental constraints (i.e., energy availability, seasonality) are key elements which explain the non-uniform pattern of species richness for this clade

Data from: Interspecific geographic range size–body size relationship and the diversification dynamics of Neotropical Furnariid birds

Among the earliest macroecological patterns documented, is the range and body size relationship, characterized by a minimum geographic range size imposed by the species' body size. This boundary for the geographic range size increases linearly with body size and has been proposed to have implications in lineages evolution and conservation. Nevertheless, the macroevolutionary processes involved in the origin of this boundary and its consequences on lineage diversification has been poorly explored. We evaluate the macroevolutionary consequences of the difference (hereafter the distance) between the observed and the minimum range sizes required by the species' body size, to untangle its role on the diversification of a Neotropical species-rich bird clade using trait-dependent diversification models. We show that speciation rate is a positive hump-shaped function of the distance to the lower boundary. The species with highest and lowest distances to minimum range size had lower speciation rates, while species close to medium distances values had the highest speciation rates. Further, our results suggest that the distance to the minimum range size is a macroevolutionary constraint that affects the diversification process responsible for the origin of this macroecological pattern in a more complex way than previously envisioned

Table S1

Table S1. Body mass and geographic range size for furnariid species in the phylogeny used in this work

Colony Size Evolution and the Origin of Eusociality in Corbiculate Bees (Hymenoptera: Apinae)

<div><p>Recently, it has been proposed that the one of the main determinants of complex societies in Hymenoptera is colony size, since the existence of large colonies reduces the direct reproductive success of an average individual, given a decreased chance of being part of the reproductive caste. In this study, we evaluate colony size evolution in corbiculate bees and their relationship with the sociality level shown by these bees. Specifically i) the correlation between colony size and level of sociality considering the phylogenetic relationship to evaluate a general evolutionary tendency, and ii) the hypothetical ancestral forms of several clades within a phylogeny of corbiculate bees, to address idiosyncratic process occurring at important nodes. We found that the level of social complexity in corbiculate bees is phylogenetically correlated with colony size. Additionally, another process is invoked to propose why colony size evolved concurrently with the level of social complexity. The study of this trait improves the understanding of the evolutionary transition from simple to complex societies, and highlights the importance of explicit probabilistic models to test the evolution of other important characters involved in the origin of eusociality.</p> </div

Phylogenetic logistic regression parameter estimates for the effect of colony size on the social structure of corbiculate bees (b₁). (a) Phylogenetic signal.

a<p>Parameters of logistic regression and standard errors of the estimates were obtained using the GEE approximation (see Ives & Garland, 2010).</p>b<p>Parametric bootstrapping was performed by simulating 2000 data sets to obtain confidence intervals. Parametric bootstrapping was also used to test the null hypotheses that there is no phylogenetic signal in the residuals (H₀: a = −4, 1-tailed test) and that the regression coefficients equal 0 (H₀: b_i = 0, 2-tailed tests).</p

Phylogenetic reconstruction of corbiculate bees based on Long Wavelength Rhodopsin and Arginine Kinase.

<p>The tree was obtained by means of a phylogenetic mixture model based on Bayesian approach. The numbers next to nodes indicate the posterior probability of occurrence of the clade. The letters above the nodes correspond to the hypothetical ancestors, whose most probable character state is shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0040838#pone-0040838-g002" target="_blank">Figures 2</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0040838#pone-0040838-g003" target="_blank">3</a>.</p

Reconstruction of the ancestral state of the colony size trait.

<p>The reconstruction was based on both topology and branch lengths of the Bayesian phylogenetic trees. In parenthesis is shown the mean value and standard error for the continuous character reconstruction.</p

Ranked table of the mean instantaneous transition rate of character state estimated under the Markov k-state evolutionary model for discrete traits.

*<p>Not applicable; set to 0.</p><p>Colony size (N° of individuals): <b>1:</b> 0 to 10; <b>2:</b> 10 to 100; <b>3:</b> 1,000 to 10,000; and <b>4:</b> over 10,000.</p><p>Level of Sociality: <b>1:</b> solitary; <b>2:</b> communal; <b>3:</b> eusocial with behavioral castes; <b>4:</b> eusocial with morphological castes.</p

Reconstruction of the ancestral state of the level of sociality trait.

<p>The reconstruction was based on both the topology and branch lengths of the Bayesian phylogenetic trees.</p