Redhead (bird) "Nassarius acutus", "Nassarius vibex", "Natica" sp., "Neritina virginea", "Odostomia trifida", "Olivella minuta", "Olivella watermani", "Polinices" sp., Pyramidellidae, "Pyrgocythara plicosa", "Rissoina catesbyana", "Sayella livida", "Turbonilla" sp., "Turbonilla interrupta" and "Vitrinella" sp. Redhead (bird) The redhead ("Aythya americana") is a medium-sized diving duck. The scientific name is derived from Greek "aithuia" an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin "americana", of America. The redhead is long with an wingspan. It belongs to the genus Aythya, together with 11 other described species. The redhead and the common pochard form a sister group which together is sister to the canvasback.
Bird-of-paradise lek-type mating system. Others, such as the "Cicinnurus" and "Parotia" species, have highly ritualised mating dances. Males are polygamous in the sexually dimorphic species, but monogamous in at least some of the monomorphic species. Hybridisation is frequent in these birds, suggesting the polygamous species of bird of paradise are very closely related despite being in different genera. Many hybrids have been described as new species, and doubt remains regarding whether some forms, such as Rothschild's lobe-billed bird of paradise, are valid. Birds-of-paradise build their nests from soft materials, such as leaves, ferns, and vine tendrils, typically placed in a tree