He visited 15 museums around the world measuring and photographing specimens from 250 million to 100 million years ago, then compared their rates of diversification.
Although these authors acknowledge the potential role of seed dispersal by ants, they suggested that there were no tests which would demonstrate whether rates of diversification were higher in myrmecochorous lineages versus those with other biotic or abiotic dispersal mechanisms.
This reflects the different mutational processes and rates of diversification associated with single amino acid changes and repeat proliferation.
In order to investigate patterns and rates of diversification within a clade, ideally nearly all the species should be sampled [22].
The rates of diversification in the later colonizers, Echium and Sideritis lineages, were about two to three times greater than those of earlier colonizers.
In addition, the rates of diversification (rD = rO−rE) and turnover (rT = rO+rE) were calculated to establish the overall change in the composition of anomodont faunas throughout the Permian and Triassic.
However, there is some evidence that clades did vary in the timing of peak rates of diversification: lineage identity was important for determining diversification potential over large periods of the lake's history.
Darwin anticipated this variability, noting that rates of diversification were "generally.on an average" autocorrelated between ancestral and descendent branches that many exceptions to the trend were to be expected as the diversity of genera waxed and waned [1].
Here we report molecular divergence estimates and rates of diversification for five representative, putative rapid radiations of monophyletic endemic plant lineages across the core eudicot clade of flowering plants.
Likewise species and genera differ in their ages [24], [25], so taxonomic autocorrelation in patterns of diversity in species and genera does not necessarily imply autocorrelation in absolute rates of diversification, but may reflect autocorrelation in phenotypic characters used in taxonomic classifications.
Both the MRP and MRC majority rule supertrees show significant shifts in net rates of diversification.
