Despite of many recent cladistic studies the classification of the order Cuculiformes is still controversial. Thus, we performed the most extensive cladistic analysis of the cuckoos, inferred based on 250 characters of the osteology, behavior and ecology. The resulting analysis provided 18 equally parsimonious trees (768 steps, CI = 0.4779, RI = 0.8080 and CRI = 0.3861). According to the topology of the strict consensus cladogram: a) the monophyly of Cuculiformes order is corroborated; b) the order is divided in two groups: a) Coua/Carpococcyx and b) others cuckoos (Neomorphidae, (Crotophagidae, (Tapera/Dromoccoccyx, (Cuculidae))), being the systematic position of Centropus ambiguous between these two groups; c) the terrestrial cuckoos are considered basal and a paraphyletic group and the arboreal cuckoos are derived and monophyletic; d) brood parasitism evolved twice in the cuckoos (in Tapera/Dromoccoccyx and in Cuculidae).
Birds; classification; cuckoos; evolution
