PENGUINS, PETRELS, AND PARSIMONY - DOES CLADISTIC-ANALYSIS OF BEHAVIOR REFLECT SEABIRD PHYLOGENY

Whether or not behavior accurately reflects evolutionary relationships (phylogeny) has been hotly debated by ethologists and comparative psy chologists. Previous studies attempting to resolve this question have generally lacked a quantitative, phylogenetic approach. In this study we used behavior and life-history (BLH) information (72 characters) to generate phylogenetic trees for 18 seabird species (albatrosses, petr els, and penguins). We compared these trees with trees obtained from i sozyme electrophoretic analysis of blood proteins (15 loci and 98 elec tromorphs) and partial mitochondrial 12S ribosomal DNA sequences (381 base pairs). Cladistic analysis of the BLH data set generated three MP trees (tree length = 243, CI = 0.52, RI = 0.57) with significant clad istic structure. The BLH characters were classified into four types (f oraging, agonistic, reproductive, and life history) and levels of homo plasy for each type were measured. No significant differences were fou nd among these categories, The BLH trees were shown to be significantl y more congruent with the electrophoretic and 12S sequence trees than expected by chance. This indicates that seabird BLH data contains phyl ogenetic signal. Areas of incongruence between BLH trees and a phyloge ny generated by combining the data sets were predicted to result from ecological constraints that did not covary with phylogeny. These predi ctions were supported by the results of a concentrated changes test. T his study found that this BLH data set was no more homoplasious than m olecular data and that BLH trees were significantly congruent with mol ecular trees.