The AU test was used (on SEA, SEAm1, SEAm2, and FEAm1) to evaluate whether these data sets could significantly discriminate between alternative hypotheses of ctenophoran opsin relationships.
We recently illustrated how molecular cytogenetics, using cohybridization FISH experiments of BAC clones (BAC-FISH), can discriminate between alternative hypotheses of synteny arrangements, orientation, and adjacencies [ 11].
Using an increased amount of sequence data we test between alternative hypotheses of soft polytomies caused by rapid speciation, slow evolutionary rate and/or insufficient sequence data, and hard polytomies caused by simultaneous speciation within this family.
The significance of the length difference between alternative hypotheses of relationships (H1 and H2) were evaluated using the Kishino-Hasegawa (KH) test under parsimony (MP) and maximum likelihood (ML), and the Wilcoxon signed-ranks test (Templeton).
Given that SEA does not seem to convey sufficient signal to discriminate between alternative hypotheses of ctenophoran-opsin relationships, we further focused on FEAm1 only and performed a posterior predictive analysis of composition, and a principal component analysis (PCA) of amino acid frequencies, to evaluate whether our results might have been affected by compositional biases.
A correct time estimation is essential for our understanding of the mechanisms underlying the diversification of orchids, and could contribute to discern between alternative hypotheses of diversification - such as significant increases in speciation rates temporally correlated to climatic changes, tectonic events, or radiation of pollinators.
The previous analyses of recombination in D. pseudoobscura [15] [17] only examined meiosis in heterozygous females, so they were not able to distinguish between the alternative hypotheses of meiotic drive and fitness effects.
Students in both semesters made significant gains in their abilities to map characters onto phylogenetic trees and to choose between two alternative hypotheses of relationship (trees) by applying the principle of parsimony (Occam's razor).
The maintenance of standing genetic variation is one remaining major evolutionary question that lacks a significant body of empirical evidence to distinguish between alternative hypotheses (Lewontin 1974), despite a rich body of theory that provides genetic models of the underlying evolutionary dynamics.
They offer a way of characterising biological systems, measuring subtle effects of perturbations, discriminating between alternative hypotheses, making and testing predictions, and following changes over time.
Second, model-driven stimulus exploration improves the quality of experimental data needed to discriminate between alternative hypotheses.
