Ivory gull narrower os pubis, and potentially more flexibility in skull kinetic structure. Structurally, it is most similar to the kittiwakes; however, recent genetic analysis based on mtDNA sequences shows that Sabine's gull is the ivory gull's closest relative, followed by the kittiwakes, with Ross's gull and swallow-tailed gull sharing a clade with these species. "Pagophila" is maintained as a unique genus because of the bird’s morphological, behavioral and ecological differences from these species. Colloquial names from Newfoundland include slob gull (from "slob", a local name for drift ice) and ice partridge, from a vague resemblance to a ptarmigan. This species is
Fork-tailed drongo-cuckoo known how or whether the drongo-like appearance benefits this species but it is suspected that it aids in brood-parasitism just as hawk-cuckoos appear like hawks. Some recent work suggested that the species was conspecific with the square-tailed drongo-cuckoo and together known as the Asian drongo-cuckoo, but should be split based on call and morphological differences. Fork-tailed drongo-cuckoo The fork-tailed drongo-cuckoo ("Surniculus dicruroides") is a species of cuckoo that resembles a black drongo. It is found resident mainly in peninsular India in hill forests although some specimens are known from the Himalayan foothills. It can be easily distinguished by its straight