Table 1

Hypotheses tested with DNA sequence data. A significant result denotes rejection of the stated hypothesis. D is the difference in length between the most parsimonious tree (8889 steps) and the tree constrained to conform to the stated hypothesis. T s is the test statistic for the Wilcoxon signed-ranks test. n is the number of characters that differed in numbers of changes on the two trees. Z is the normal approximation when n > 100 (25). “Difference” is the difference in negative log likelihoods between the maximum likelihood tree (–ln L = 41,059.9) and the tree constrained to conform to the stated hypothesis. t is the Student‘s t test statistic.

HypothesisDTsnZParsimonyP valueLikelihood differencetLikelihoodP value
Monophyly of ecomorph class
Shortest tree with
16 ecomorph transitions52,7061060.40.68351.11.40.171
15 ecomorph transitions256,4441721.50.128103.12.70.007
14 ecomorph transitions487,8031982.50.011212.34.5<0.001