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Bird Measurement
Bird measurement or bird biometrics are approaches to quantify the size of birds in scientific studies. The variation in dimensions and weights across birds is one of the fundamental sources of diversity among birds, and even Within species, dimensions may vary across populations Intraspecific variability, within species, between the sexes and depending on Biomarkers of aging, age and condition. For measurements to be useful, they must be well-defined to be consistent and comparable with those taken by others or at other points in time. Measurements can be useful to identify species, quantify functional and ecomorphology, ecomorphological differences, study growth, variation between geographically separated forms, identify Sexual dimorphism measures, differences between the sexes, age or otherwise characterize individual birds. While certain measurements are regularly taken to study living birds, others apply only to specimens in bird collections or are measurable only in the labo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multivariate Statistics
Multivariate statistics is a subdivision of statistics encompassing the simultaneous observation and analysis of more than one outcome variable, i.e., '' multivariate random variables''. Multivariate statistics concerns understanding the different aims and background of each of the different forms of multivariate analysis, and how they relate to each other. The practical application of multivariate statistics to a particular problem may involve several types of univariate and multivariate analyses in order to understand the relationships between variables and their relevance to the problem being studied. In addition, multivariate statistics is concerned with multivariate probability distributions, in terms of both :*how these can be used to represent the distributions of observed data; :*how they can be used as part of statistical inference, particularly where several different quantities are of interest to the same analysis. Certain types of problems involving multivariate da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Flight
Bird flight is the primary mode of animal locomotion, locomotion used by most bird species in which birds take off and flight, fly. Flight assists birds with feeding, Sexual reproduction, breeding, avoiding predation, predators, and Bird migration, migrating. Bird flight includes multiple types of motion, including hovering, taking off, and landing, involving many complex movements. As different bird species adapted over millions of years through evolution for specific environments, prey, predators, and other needs, they developed Generalist and specialist species, specializations in their wing (bird), wings, and acquired different forms of flight. Various theories exist about how bird flight evolution, evolved, including flight from falling or gliding (the ''trees down'' hypothesis), from running or leaping (the ''ground up'' hypothesis), from ''wing-assisted incline running'' or from '' proavis'' (pouncing) behavior. Basic mechanics of bird flight Lift, drag and thrust The f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ImageJ
ImageJ is a Java (programming language), Java-based image processing program developed at the National Institutes of Health and the Laboratory for Optical and Computational Instrumentation (LOCI, University of Wisconsin). Its first version, ImageJ 1.x, is developed in the public domain, while ImageJ2 and the related projects SciJava, ImgLib2, and SCIFIO are licensed with a permissive BSD licenses, BSD-2 license. ImageJ was designed with an open architecture that provides extensibility via Java plug-in (computing), plugins and recordable macros. Custom acquisition, analysis and processing plugins can be developed using ImageJ's built-in editor and a Java compiler. User-written plugins make it possible to solve many image processing and analysis problems, from three-dimensional live-cell imaging to radiology, radiological image processing, multiple imaging system data comparisons to automated hematology systems. ImageJ's plugin architecture and built-in development environment has mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planimeter
A planimeter, also known as a platometer, is a measuring instrument used to determine the area of an arbitrary two-dimensional shape. Construction There are several kinds of planimeters, but all operate in a similar way. The precise way in which they are constructed varies, with the main types of mechanical planimeter being polar, linear, and Prytz or "hatchet" planimeters. The Swiss mathematician Jakob Amsler-Laffon built the first modern planimeter in 1854, the concept having been pioneered by Johann Martin Hermann in 1818. Many developments followed Amsler's famous planimeter, including electronic versions. The Amsler (polar) type consists of a two-bar linkage. At the end of one link is a pointer, used to trace around the boundary of the shape to be measured. The other end of the linkage pivots freely on a weight that keeps it from moving. Near the junction of the two links is a measuring wheel of calibrated diameter, with a scale to show fine rotation, and worm gearing for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Flight
Bird flight is the primary mode of animal locomotion, locomotion used by most bird species in which birds take off and flight, fly. Flight assists birds with feeding, Sexual reproduction, breeding, avoiding predation, predators, and Bird migration, migrating. Bird flight includes multiple types of motion, including hovering, taking off, and landing, involving many complex movements. As different bird species adapted over millions of years through evolution for specific environments, prey, predators, and other needs, they developed Generalist and specialist species, specializations in their wing (bird), wings, and acquired different forms of flight. Various theories exist about how bird flight evolution, evolved, including flight from falling or gliding (the ''trees down'' hypothesis), from running or leaping (the ''ground up'' hypothesis), from ''wing-assisted incline running'' or from '' proavis'' (pouncing) behavior. Basic mechanics of bird flight Lift, drag and thrust The f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wing Chord (biology)
Wing chord is an anatomical measurement of a bird's wing A wing is a type of fin that produces both Lift (force), lift and drag while moving through air. Wings are defined by two shape characteristics, an airfoil section and a planform (aeronautics), planform. Wing efficiency is expressed as lift-to-d .... The measurement is taken with the wing bent at a 90-degree angle, from the most prominent point of the wrist joint to the most prominent point of the longest primary feather. It is often taken as a standard measurement of the proportions of a bird and used to differentiate between species and subspecies. See also * Bird measurement References {{Bird-stub Bird anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bustard
Bustards, including floricans and korhaans, are large, terrestrial birds living mainly in dry grassland areas and in steppe regions. They range in length from . They make up the family Otididae (, formerly known as Otidae). Bustards are omnivorous and opportunistic, eating leaves, buds, seeds, fruit, small vertebrates, and invertebrates.del Hoyo, J. Elliott, A. & Sargatal, J. (editors). (1996) ''Handbook of the Birds of the World. Volume 3: Hoatzin to Auks''. Lynx Edicions. There are 26 species currently recognised. Etymology The word ''bustard'' comes from the Old French ''bistarda'' and some other languages: ''abetarda'' ( pt), ''abetarda'' ( gl), ''avutarda'' ( es) used for the great bustard. The naturalist William Turner listed the English spelling "bustard" and "bistard" in 1544. All of the common names above are derived from Latin ''avis tarda'' or ''aves tardas'' given by Pliny the Elder, these names were mentioned by the Pierre Belon in 1555 and Ulisse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crane (bird)
Cranes are a type of large bird with long legs and necks in the Family (biology), biological family Gruidae of the Order (biology), order Gruiformes. The family has 15 species placed in four genera which are ''Antigone (genus), Antigone'', ''Balearica'', ''Siberian crane, Leucogeranus'', and ''Grus (genus), Grus''. They are large birds with long necks and legs, a tapering form, and long secondary feathers on the wing that project over the tail. Most species have muted gray or white plumages, marked with black, and red bare patches on the face, but the crowned cranes of the genus ''Balearica'' have vibrantly-coloured wings and golden "crowns" of feathers. Cranes fly with their necks extended outwards instead of bent into an S-shape and their long legs outstretched. Cranes live on most continents, with the exception of Antarctica and South America. Some species and populations of cranes bird migration, migrate over long distances; others do not migrate at all. Cranes are solitary du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarsometatarsus
The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bird bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) and metatarsal bones (foot). Despite this, the tarsometatarsus of flying types is often referred to as just the shank, tarsus or metatarsus. Tarsometatarsal fusion occurred in several ways and extents throughout bird evolution. Paticularly, in Neornithes (modern birds), although the bones are joined along their entire length, the fusion is most thorough at the distal (metatarsal) end. In the Enantiornithes, a group of Mesozoic avialans, the fusion was complete at the proximal (tarsal) end, but the distal metatarsi were still partially distinct. While these fused bones are best known from birds and their relatives, avians are neither the only group nor the first to possess tarsometatarsi. In a remarkable case of parallel evolution, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
