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Gull 2 G-ACGR Brussels
Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century, most gulls were placed in the genus ''Larus'', but that arrangement is now considered polyphyletic, leading to the resurrection of several genera. An older name for gulls is mews, which is cognate with German ''Möwe'', Danish ''måge'', Swedish ''mås'', Dutch ''meeuw'', Norwegian ''måke''/''måse'' and French ''mouette'', and can still be found in certain regional dialects. Gulls are typically medium to large in size, usually grey or white, often with black markings on the head or wings. They typically have harsh wailing or squawking calls; stout, longish bills; and webbed feet. Most gulls are ground-nesting carnivores which take live food or scavenge opportunistically, particularly the ''Larus'' species. Live food often includes crustacea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Oligocene
The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian Stage. Name The stage is named after the small river Rupel in Belgium, a tributary to the Scheldt. The Belgian Rupel Group derives its name from the same source. The name Rupelian was introduced in scientific literature by Belgian geologist André Hubert Dumont in 1850. The separation between the group and the stage was made in the second half of the 20th century, when stratigraphers saw the need to distinguish between lithostratigraphic and chronostratigraphic names. Stratigraphic definition The base of the Rupelian Stage (which is also the base of the Oligocene Series) is at the extinction of the foraminiferan genus ''Hantkenina''. An official GSSP for the base of the Rupelian has been assigned in 1992 (Massignano, Italy). The transi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobbing (animal Behavior)
Mobbing in animals is an antipredator adaptation in which individuals of prey species mob a predator by cooperatively attacking or harassing it, usually to protect their offspring. A simple definition of mobbing is an assemblage of individuals around a potentially dangerous predator. This is most frequently seen in birds, though it is also known to occur in many other animals such as the meerkat and some bovines. While mobbing has evolved independently in many species, it only tends to be present in those whose young are frequently preyed upon. This behavior may complement cryptic adaptations in the offspring themselves, such as camouflage and hiding. Mobbing calls may be used to summon nearby individuals to cooperate in the attack. Konrad Lorenz, in his book ''On Aggression'' (1966), attributed mobbing among birds and animals to instincts rooted in the Darwinian struggle to survive. In his view, humans are subject to similar innate impulses but capable of bringing them under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Gull
The lava gull (''Leucophaeus fuliginosus''), also known as the dusky gull, is a medium-sized gull and a member of the "hooded gull" group. It is most closely related to the Laughing gull and Franklin's gull and is the rarest gull in the world. It is endemic to the Galapagos Islands. Taxonomy and systematics First described by John Gould in 1841 from a specimen collected on Santiago Island in the Galápagos. The species is sometimes placed in the genus ''Larus''. It is possibly closely related to the laughing gull. Description The lava gull is a distinctive gull, and weighs . The adult plumage consists of a sooty brown to black head, which unlike other dark hooded gulls doesn't vary by season. The wings are dark gray with a contrasting white line on the leading edge, thought to play a function in displays and camouflage. Its dark gray body contrasts with a paler gray belly. The uppertail is white and grey lower down. The bill and legs are black, and the inside of the mouth is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ivory Gull
The ivory gull (''Pagophila eburnea'') is a small gull, the only species in the genus ''Pagophila''. It breeds in the high Arctic and has a circumpolar distribution through Greenland, northernmost North America, and Eurasia. Taxonomy The ivory gull was initially described by Constantine Phipps, 2nd Baron Mulgrave in 1774 as ''Larus eburneus'' from a specimen collected on Spitsbergen during his 1773 expedition towards the North Pole. Johann Jakob Kaup later recognized the unique traits of the ivory gull and gave it a monotypic genus, ''Pagophila'', in 1829. Johan Ernst Gunnerus later gave the species a new specific name, ''Pagophila alba''. The genus name ''Pagophila'' is from Ancient Greek ''pagos'', "sea-ice", and ''philos'', "-loving", and specific ''eburnea'' is Latin for "ivory-coloured", from ''ebur'', "ivory". Today some authors consider the ivory gull not deserving of its monotypic genus, instead choosing to merge it, along with the other monotypic gulls, back into '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
