38 research outputs found
This table summarizes the ability of the various partitions to identify well-established relationship amongst echinoderms other than the Asteroidea.
<p>This table summarizes the ability of the various partitions to identify well-established relationship amongst echinoderms other than the Asteroidea.</p
Current competing hypotheses of relationships derived from morphological or molecular data for the major starfish clades considered in this paper.
<p>Current competing hypotheses of relationships derived from morphological or molecular data for the major starfish clades considered in this paper.</p
Resultant tree from analysis of the homogenous rates and compositional data set under CAT-GTR-Γ.
<p>Support at the nodes indicates posterior probability under CAT-GTR- Γ (bold), posterior probability GTR- Γ (italic bold) and maximum likelihood abayes bootstrap under GTR- Γ (italic).</p
Key morphological characters relevant to asteroid rooting mapped onto our best-supported molecular phylogenetic tree.
<p>1, planktotrophic larval development; ☐ to bipinnaria stage; ■to brachiolaria stage; L—lecithotrophic (no planktotrophic larval stage). 2, suckered tube feet; ☐ absent; ■present. 3, pedicellariae; ☐ simple valves; ■ complex, crossed pedicellarae with basal element. 4, oral frame; ☐ ambulacral; ■ adambulacral. 5, eversible stomach; ☐ absent; ■ present. 6, anus; ☐ absent; ■ present.</p
Bayes Factor support for the alterative topologies in the different partitions.
<p>Supports are coded according to [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0123331#pone.0123331.ref045" target="_blank">45</a>]. Rates hom. = homogeneous rates partition; comp. hom. = compositionally homogeneous partition; rates+comp. hom. = homogeneous rates and composition partition; rates heter. = heterogeneous rates partition. In this table the red color implies that competing tree is rejected and the darker the red the stronger the evidence for rejection.</p
Patterns of richness and sampling proxies through the Phanerozoic.
<p>A) Distribution of genus richness across paleolatitude strips. B) Distribution of total equal area grid cells with at least one fossil locality recorded in the PaleoDB across paleolatitude strips. C) Distribution of faunal lists with collection IDs in the PaleoDB across paleolatitude strips. D) The percentage variation of richness in each paleolatitude strips explained by geographic coverage and sampling intensity in each of those paleolatitude strips. Note that the sampling proxies are not rendundant; parts of the Phanerozoic lack geographic coverage but have high sampling intensity and vice versa. Each interval is shaded by the color of the model with the lowest AIC score.</p
Diversity and sampling bias in latitude strips.
<p>A–B) Number of grid cells with sampled fossils for each time bin within two fixed paleolatiutudinal belts (temperate and equatorial). A gradual increase in sampled grid cells is evident in the temperate strip (A), while no such pattern is evident in the equatorial strip (B). C–D) Mean richness per sampled grid cell reveals no obvious pattern for faunas in the two paleolatitudinal belts. E–F) Null model that assumes biodiversity is driven purely by sampling (black) compared with observed genus richness (red). The null model explains the overall signal in the data, but select portions of the Phanerozoic deviate from the expectation. G–H) Plots show the difference between empirical richness and the expectation of the null model. Dashed bars indicate 99% confidence intervals for the null model. Overall, we find that the temperate and tropical faunas have similar trajectories despite markedly different trends in spatial sampling pattern over time.</p
Spatial shifts in fossil occurrences through the Phanerozoic.
<p>A) The median latitude of fossil occurrences steadily rises through the Phanerozoic, but is punctuated by short-term noise and contractions and expansions of geographic coverage. Error bars indicate 25th and 75th quantiles, while the red line is a moving average across five points. B) The Mann-Whitney U test statistic plotted for each interval. A higher test-statistic corresponds to a more severe change in latitude. All transitions are statistically significant but vary in their effect size.</p
500,000 meter equal area gridding scheme for geographic coverage measure superimposed on a geographic map of the present day.
<p>This measure is equal to the number of equal area cells in a paleolatitude strip with fossil occurrences of our target taxa.</p
The distribution of genus richness across latitudes plotted for key intervals.
<p>A) For the last three Cenozoic time intervals (Cenozoic 4–6), Cenozoic 6 has more equitable sampling across latitudes than its predecessors. B) The Permo-Carboniferous boundary reflects a weakness in geographic coverage that biases estimates of global diversity inferred by subsampling.</p