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NIALL PERRINS pete oxford

f they are not calling, nightjars can be closely related to the other caprimulgiforms above Madagascar’s Collared , one of the trickiest groups of to (Molecular Phylogenetics and Evolution 41: formerly placed in , appears to be identify. How often have you been out 238–248). And within the nightjars, the tra- an ancient lineage and should be placed in its Iat night, spot-lighting, and just about con- ditional division placing the nightjars and own genus, Gactornis. vinced yourself you are looking at a Rufous- nighthawks in separate subfamilies was not cheeked Nightjar, only to have it start calling supported. One of the South-East Asian and above, left Genetic studies show that the ‘good-lord-deliver-us’? The problem is that Australasian eared-nightjars (Eurostopodus extravagant wing plumes of the Pennant- nightjars’ appearance is driven by the need macrotis) emerged as the basal form, sup- winged Nightjar are a derived feature, and for excellent camouflage during the day, so porting Sibley and Ahlquist’s results from that the genus Macrodipteryx should be if they roost in the same habitat, they tend DNA-DNA hybridisation. placed within Caprimulgus. to look the same. More recently, Kin-Lan Han and col- This similarity runs deeper than just su- leagues from the Smithsonian Institution and Caprimulgus species currently are as- perficial appearances. Because the majority extended this analysis, including many signed to three of these four groups. The of nightjars forage in a similar fashion, their more species of nightjars and nighthawks Chordeiles and Podager nighthawks form one structure is also similar, leading to consider- (Molecular Phylogenetics and Evolution 55: group, but the two other nighthawk genera, able debate over how best to classify them 443–453). They confirmed that the eared- Lurocalis and Nyctiprogne, are placed in an- to genera and higher taxonomic group- nightjars are indeed the basal group within other of the New World nightjar groups. ings. Traditionally five families have been the Caprimulgidae­ and suggest that they be The Old World group of nightjars com- recognised in the order : placed in their own subfamily or even a sepa- prises only two genera: Caprimulgus and the widespread nightjars and nighthawks rate family. Among the remaining species, Macrodipteryx. The latter genus is based on (Caprimulgidae), New World potoos (Nyc­ Madagascar’s Collared Nightjar, currently the extravagant wing plumes of the male tibidae), South-East Asian and Australasian placed in Caprimulgus, is distinct from all Pennant-winged Nightjar, and its West Afri- frogmouths (Podargidae), Australasian other species and should be placed in its own can counterpart, the Standard-winged Night- owlet-nightjars (Aegolthelidae), and the genus, Gactornis. By comparison, the more jar. Although Han’s study shows that these New World Oilbird (Steatornithidae). But common Madagascar Nightjar Caprimul- two species are each other’s closest relatives, the application of molecular approaches has gus madagascariensis is closely related to the they are embedded within the Old World resulted in a few surprises. many African Caprimulgus species. Caprimulgus species, and as such should be In 2006, George Barrowclough and his Han’s results show that Caprimulgus re- placed within Caprimulgus. So Africa is set colleagues from the American Museum quires extensive revision. The primary radia- to lose an endemic nightjar genus, but this is of Natural History confirmed that despite tion of nightjars follows geographic bounda- offset by the recognition of the importance of their appearance, owlet-nightjars are sister ries, with one group confined to the Old Madagascar’s Collared Nightjar. to the swifts and hummingbirds, and not World and three groups to the New World, Peter Ryan

january/february 2014 news & views 13