|
Wing Chord (biology)
Wing chord is an anatomical measurement of a bird's wing. 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 Bird measurement or bird biometrics are approaches to quantify the size of birds in scientific studies. The measurements of the lengths of specific parts and the weights of birds varies between species, populations within species, between the sex ... References {{Bird-stub Bird anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. There are about ten thousand living species, more than half of which are passerine, or "perching" birds. Birds have whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the loss of flight in some birds, including ratites, penguins, and diverse endemic island species. The digestive and respiratory systems of birds are also uniquely adapted for flight. Some bird species of aquatic environments, particularly seabirds and some waterbirds, have further evolved for swimming. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wing
A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is expressed as its lift-to-drag ratio. The lift a wing generates at a given speed and angle of attack can be one to two orders of magnitude greater than the total drag on the wing. A high lift-to-drag ratio requires a significantly smaller thrust to propel the wings through the air at sufficient lift. Lifting structures used in water include various foils, such as hydrofoils. Hydrodynamics is the governing science, rather than aerodynamics. Applications of underwater foils occur in hydroplanes, sailboats and submarines. Etymology and usage For many centuries, the word "wing", from the Old Norse ''vængr'', referred mainly to the foremost limbs of birds (in addition to the architectural aisle). But in recent centuries the word's meaning has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Feather
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail are called rectrices (), singular rectrix (). The primary function of the flight feathers is to aid in the generation of both thrust and lift, thereby enabling flight. The flight feathers of some birds have evolved to perform additional functions, generally associated with territorial displays, courtship rituals or feeding methods. In some species, these feathers have developed into long showy plumes used in visual courtship displays, while in others they create a sound during display flights. Tiny serrations on the leading edge of their remiges help owls to fly silently (and therefore hunt more successfully), while the extra-stiff rectrices of woodpeckers help them to brace against tree trunks as they hammer on them. Even flightless birds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Measurement
Bird measurement or bird biometrics are approaches to quantify the size of birds in scientific studies. The measurements of the lengths of specific parts and the weights of birds varies between species, populations within species, between the sexes and depending on age and condition. In order for measurements to be useful, they need to be well defined so that measurements taken are consistent and comparable with those taken by others or at other points of time. Measurements can be useful to study growth, variation between geographically separated forms, identify differences between the sexes, age or otherwise characterize individuals birds. While certain measurements are regularly taken in the field to study living birds some others are applicable only to specimens in the museum or measurable only in a laboratory. The conventions used for measurement can vary widely between authors and works, making comparisons of sizes a matter that needs considerable care. Methods and considera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Bird")
.jpg "Click for more on -> Primary Feather")
