A phylogenetic study of the Malagasy Couas with insights into cuckoo relationships

The avian family Cuculidae (cuckoos) is a diverse group of birds that vary considerably in behaviors of interest to behavioral ecologists, e.g., oblig ate brood parasitism and cooperative breeding. The taxonomy of this group h as historically been relatively stable but has not been extensively evaluat ed using molecular methods. The goal of this study was to evaluate phylogen etic relationships within the ecologically diverse genus Coua and the place ment of Coua among major cuckoo lineages, We sequenced 429 bp of cytochrome b (cyt b) and 522 bp of ND2, both mitochondrial genes, for 26 species of c uckoos spanning 13 genera, We also included the enigmatic hoatzin (Opisthoc omus hoazin) and used two Tauraco species as outgroups, ND2 exhibited highe r rates of DNA sequence and amino acid substitution than cyt b;however, thi s did not greatly affect the overall levels of phylogenetic resolution and support provided by these two genes. Combined analyses produced two alterna tive phylogenies, depending on weighting scheme, both of which were fully r esolved and were characterized by high bootstrap support. These phylogenies recovered monophyly for all of the traditional cuckoo subfamilies and indi cated, with strong support, that the hoatzin is outside of Cuculidae. Withi n Coua, an arboreal and a terrestrial clade were identified. In contrast, h abitat choice of Coua species did not greatly reflect the phylogeny, (C) 20 00 Academic Press.