83-645: Birds are a group of warm-blooded vertebrates constituting the class Aves ( Latin: [ˈaveːs] ), 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 5.5 cm (2.2 in) bee hummingbird to the 2.8 m (9 ft 2 in) common ostrich . There are over 11,000 living species and they are split into 44 orders . More than half are passerine or "perching" birds. Birds have wings whose development varies according to species;
166-402: A citizen science project used by ornithologists to document trends in bird populations, it allows birders see recent reports by other birders and search by species and location. Some species, including endangered species and others likely to be disrupted by increased human activity, are designated "sensitive species" by eBird and have locations of sightings hidden from the general public. As
249-484: A country list , state list , county list , yard list , year list , or any combination of these. The early interest in observing birds for their aesthetic rather than utilitarian (mainly food) value is traced to the late 18th century in the works of Gilbert White , Thomas Bewick , George Montagu and John Clare . The study of birds, and of natural history in general, became increasingly prevalent in Britain during
332-404: A golden-winged warbler ( Vermivora chrysoptera ), which is native to North America. Twitchers have developed their own vocabulary . For example, a twitcher who fails to see a rare bird has dipped out ; if other twitchers do see the bird, they may feel gripped off . Suppression is the act of concealing news of a rare bird from other twitchers. Many birders maintain a life list , that is,
415-477: A spotting scope with tripod , a smartphone , a notepad, and one or more field guides . Hides (known as blinds in North America) or observation towers are often used to conceal the observers from birds, and/or to improve viewing conditions. Virtually all optics manufacturers offer specific binoculars for birding, and some have even geared their whole brand to birders. Recognition of bird vocalizations
498-698: A better sense of smell. A third stage of bird evolution starting with Ornithothoraces (the "bird-chested" avialans) can be associated with the refining of aerodynamics and flight capabilities, and the loss or co-ossification of several skeletal features. Particularly significant are the development of an enlarged, keeled sternum and the alula , and the loss of grasping hands. † Anchiornis † Archaeopteryx † Xiaotingia † Rahonavis † Jeholornis † Jixiangornis † Balaur † Zhongjianornis † Sapeornis † Confuciusornithiformes † Protopteryx † Pengornis Ornithothoraces † Enantiornithes Warm-blooded Warm-blooded
581-453: A defense against fungal infections . Very few fungi can survive the body temperatures of warm-blooded animals. By comparison, insects, reptiles, and amphibians are plagued by fungal infections. Warm-blooded animals have a defense against pathogens contracted from the environment, since environmental pathogens are not adapted to their higher internal temperature. Footnotes Citations Birdwatching Birdwatching , or birding ,
664-470: A definition similar to "all theropods closer to birds than to Deinonychus ", with Troodon being sometimes added as a second external specifier in case it is closer to birds than to Deinonychus . Avialae is also occasionally defined as an apomorphy-based clade (that is, one based on physical characteristics). Jacques Gauthier , who named Avialae in 1986, re-defined it in 2001 as all dinosaurs that possessed feathered wings used in flapping flight , and
747-485: A distance away from nests and nesting colonies, and respecting private property. The lack of definite evidence, except arguably in the form of photographs, makes birding records difficult to prove but birdwatchers strive to build trust in their identification. One of the few major disputes was the case of the Hastings Rarities . Ethologist Nikolaas Tinbergen considers birdwatching to be an expression of
830-440: A group called Paraves . Some basal members of Deinonychosauria, such as Microraptor , have features which may have enabled them to glide or fly. The most basal deinonychosaurs were very small. This evidence raises the possibility that the ancestor of all paravians may have been arboreal , have been able to glide, or both. Unlike Archaeopteryx and the non-avialan feathered dinosaurs, who primarily ate meat, studies suggest that
913-529: A higher basal metabolic rate and can further increase their metabolic rate during strenuous activity. They usually have well-developed insulation in order to retain body heat: fur and blubber in the case of mammals and feathers in birds. When this insulation is insufficient to maintain body temperature, they may resort to shivering —rapid muscle contractions that quickly use up ATP, thus stimulating cellular metabolism to replace it and consequently produce more heat. Additionally, almost all eutherian mammals (with
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#1732766127421996-562: A list of all of the species they have seen in their life, usually with details about the sighting such as date and location. The American Birding Association has specific rules about how a bird species may be documented and recorded in such a list if it is submitted to the ABA; however, the criteria for the personal recording of these lists are very subjective. Some birders "count" species they have identified audibly, while others only record species that they have identified visually. Some also maintain
1079-414: A list. The term originated in the 1950s, when it was used to describe the nervous behaviour of Howard Medhurst, a British birdwatcher. Earlier terms for those who chased rarities were pot-hunter , tally-hunter , or tick-hunter . The main goal of twitching is often to accumulate species on one's lists. Some birders engage in competition to accumulate the longest species list. The act of the pursuit itself
1162-484: A major business, with at least 127 companies offering tours worldwide. An average trip to a less-developed country costs $ 4,000 per person and includes about 12 participants for each of 150 trips a year. It has been suggested that this economic potential needs to be tapped for conservation. Birdwatching tourism is considered to be one of the fastest-growing nature-based tourism sectors in the world, often involving well-educated or wealthy travelers with specific interests in
1245-808: A minimum of 10% of its net profits to bird conservation and communities it operates in. Another tour operator, Hardy Boat, has donated $ 200,000 to Project Puffin to conserve puffin populations off the Atlantic Coast. One of the expectations of ecotourism is that the travels of birders to a place will contribute to the improvement of the local economy, ensuring that the environment is valued and protected. Birdwatchers contribute to conservation, helping build and disseminate environmental knowledge by participating in citizen science. However, birding can bring about an increased penetration of ecosystem services that are perceived as birdwatchers' indispensable attributes. By their presence and obstinacy, birdwatchers affect
1328-590: A more limited scope, perhaps not venturing far from their own yards or local parks to view birds. Indeed, in 1969 a Birding Glossary appeared in Birding magazine which gave the following definitions: Birder . The acceptable term used to describe the person who seriously pursues the hobby of birding. May be professional or amateur. Birding . A hobby in which individuals enjoy the challenge of bird study, listing, or other general activities involving bird life. Bird-watcher . A rather ambiguous term used to describe
1411-449: A much more widespread aspect of the hobby. As with the arrival of affordable digital cameras , the development of more compact and affordable digital video cameras has made them more attractive and accessible to the birding community. Cross-over, non-linear digital models now exist that take high-quality stills at acceptable resolutions, as well as being able to record and play audio and video. The ability to capture and reproduce not only
1494-408: A part of birding, but in the past the cost of cameras with super-telephoto lenses made this a minority, often semi-professional, interest. The advent of affordable digital cameras , which can be used in conjunction with a spotting scope or binoculars (using the technique of afocal photography , referred to by the neologism " digiscoping " or sometimes digibinning for binoculars), have made this
1577-629: A possibility for a large number of people towards the 1980s. The need for global guides to birds increased, and one of the biggest resulting projects was the Handbook of the Birds of the World , begun in the 1990s by Josep del Hoyo, Jordi Sargatal, David A. Christie, and ornithologist Andy Elliott. Initially, birdwatching was largely restricted to developed countries such as the United Kingdom and
1660-405: A sister group, the order Crocodilia , contain the only living representatives of the reptile clade Archosauria . During the late 1990s, Aves was most commonly defined phylogenetically as all descendants of the most recent common ancestor of modern birds and Archaeopteryx lithographica . However, an earlier definition proposed by Jacques Gauthier gained wide currency in the 21st century, and
1743-717: A time, sometimes for years, and rarely for life. Other species have breeding systems that are polygynous (one male with many females) or, rarely, polyandrous (one female with many males). Birds produce offspring by laying eggs which are fertilised through sexual reproduction . They are usually laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching. Many species of birds are economically important as food for human consumption and raw material in manufacturing, with domesticated and undomesticated birds being important sources of eggs, meat, and feathers. Songbirds , parrots, and other species are popular as pets. Guano (bird excrement)
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#17327661274211826-576: A useful tool for environmental education and awareness of environmental issues. Birdwatching can increase respect for nature and awareness of the fragility of ecosystems . Birding as a competitive event is organized in some parts of the world. Such competitions encourage individuals or teams to accumulate large numbers of species within a specified time or area with special rules. Some birdwatchers will also compete by attempting to increase their life list, national list, state list, provincial list, county list, or year list . The American Birding Association
1909-496: Is generated by metabolism . This relates to the chemical reaction in cells that break down glucose into water and carbon dioxide , thereby producing adenosine triphosphate (ATP), a high-energy compound used to power other cellular processes. Muscle contraction is one such metabolic process generating heat energy, and additional heat results from friction as blood circulates through the vascular system. All organisms metabolize food and other inputs, but some make better use of
1992-424: Is an important part of a birder's toolkit. Sound information can assist in the locating, watching, identification, and sometimes sexing of birds. Recent developments in audio technology have seen recording and reproduction devices shrink in both size and price, making them accessible to a greater portion of the birding community. The non-linear nature of digital audio technology has also made selecting and accessing
2075-412: Is an informal term referring to animal species whose bodies maintain a temperature higher than that of their environment. In particular, homeothermic species (including birds and mammals ) maintain a stable body temperature by regulating metabolic processes. Other species have various degrees of thermoregulation . As there are more than two categories of temperature control utilized by animals,
2158-540: Is called ornithology . Birds are feathered theropod dinosaurs and constitute the only known living dinosaurs . Likewise, birds are considered reptiles in the modern cladistic sense of the term, and their closest living relatives are the crocodilians . Birds are descendants of the primitive avialans (whose members include Archaeopteryx ) which first appeared during the Late Jurassic . According to recent estimates, modern birds ( Neornithes ) evolved in
2241-434: Is estimated that birdwatching ecotourism contributes $ 41 billion per year to the U.S. economy. The large funds generated by birdwatching ecotourism have been suggested as a replacement for tax revenue generated by bird hunting which has dropped to its lowest levels in decades. Birding ecotourism companies are also making contributions to conservation. Birding Ecotours, which runs both international and domestic trips, donates
2324-429: Is harvested for use as a fertiliser. Birds figure throughout human culture. About 120 to 130 species have become extinct due to human activity since the 17th century, and hundreds more before then. Human activity threatens about 1,200 bird species with extinction, though efforts are underway to protect them. Recreational birdwatching is an important part of the ecotourism industry. The first classification of birds
2407-500: Is not considered a direct ancestor of birds, though it is possibly closely related to the true ancestor. Over 40% of key traits found in modern birds evolved during the 60 million year transition from the earliest bird-line archosaurs to the first maniraptoromorphs , i.e. the first dinosaurs closer to living birds than to Tyrannosaurus rex . The loss of osteoderms otherwise common in archosaurs and acquisition of primitive feathers might have occurred early during this phase. After
2490-595: Is referred to as a twitch or a chase . A rare bird that stays long enough for people to see it is twitchable or chaseable . Twitching is highly developed in the United Kingdom, the Netherlands , Denmark , Ireland , Finland and Sweden . The size of these countries makes it possible to travel throughout them quickly and with relative ease. The most popular twitches in the UK have drawn large crowds; for example, approximately 2,500 people travelled to Kent , to view
2573-513: Is synonymous to Avifilopluma. † Scansoriopterygidae † Eosinopteryx † Jinfengopteryx † Aurornis † Dromaeosauridae † Troodontidae Avialae Based on fossil and biological evidence, most scientists accept that birds are a specialised subgroup of theropod dinosaurs and, more specifically, members of Maniraptora , a group of theropods which includes dromaeosaurids and oviraptorosaurs , among others. As scientists have discovered more theropods closely related to birds,
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2656-443: Is the observing of birds , either as a recreational activity or as a form of citizen science . A birdwatcher may observe by using their naked eye, by using a visual enhancement device such as binoculars or a telescope , by listening for bird sounds, watching public webcams , or by viewing smart bird feeder cameras. Most birdwatchers pursue this activity for recreational or social reasons, unlike ornithologists , who engage in
2739-533: Is used by many scientists including adherents to the PhyloCode . Gauthier defined Aves to include only the crown group of the set of modern birds. This was done by excluding most groups known only from fossils , and assigning them, instead, to the broader group Avialae, on the principle that a clade based on extant species should be limited to those extant species and their closest extinct relatives. Gauthier and de Queiroz identified four different definitions for
2822-584: The Sibley Guide to Birds and the official Audubon Society app. Other apps utilize machine learning to automatically identifying birds from photographs and audio recordings, such as the Cornell Lab of Ornithology's Merlin Bird ID application and iNaturalist . Cornell Lab of Ornithology 's eBird database is a popular tool used by birders to document their sightings. In addition to serving as
2905-852: The American Birding Association and the Cornell Lab of Ornithology in North America. Many statewide or local Audubon organizations are also active in the United States, as are many provincial and local organizations in Canada. BirdLife International is an important global alliance of bird conservation organizations. Many countries and smaller regions (states/provinces) have "rarities committees" to check, accept or reject reports of rare birds made by birders. Equipment commonly used for birding includes binoculars ,
2988-488: The Christmas Bird Count , or follow carefully designed study protocols. This kind of citizen science can assist in identifying environmental threats to the well-being of birds or, conversely, in assessing outcomes of environmental management initiatives intended to ensure the survival of at-risk species or to encourage the breeding of species for aesthetic or ecological reasons. This more scientific side of
3071-721: The Late Cretaceous and diversified dramatically around the time of the Cretaceous–Paleogene extinction event 66 million years ago, which killed off the pterosaurs and all non- ornithuran dinosaurs. Many social species preserve knowledge across generations ( culture ). Birds are social, communicating with visual signals, calls, and songs , and participating in such behaviour as cooperative breeding and hunting, flocking , and mobbing of predators. The vast majority of bird species are socially (but not necessarily sexually) monogamous , usually for one breeding season at
3154-668: The Tiaojishan Formation of China, which has been dated to the late Jurassic period ( Oxfordian stage), about 160 million years ago. The avialan species from this time period include Anchiornis huxleyi , Xiaotingia zhengi , and Aurornis xui . The well-known probable early avialan, Archaeopteryx , dates from slightly later Jurassic rocks (about 155 million years old) from Germany . Many of these early avialans shared unusual anatomical features that may be ancestral to modern birds but were later lost during bird evolution. These features include enlarged claws on
3237-468: The Victorian Era , often associated with collection , eggs and later skins being the artifacts of interest. Wealthy collectors made use of their contacts in the colonies to obtain specimens from around the world. It was only in the late 19th century that the call for bird protection led to the rising popularity of observations of living birds. The Audubon Society was started to protect birds from
3320-519: The World Wide Web , birders have been using the Internet to convey information; this can be via mailing lists , forums , bulletin-boards , web-based databases and other social media . While most birding lists are geographic in scope, there are special-interest lists that cater to bird-identification, 'twitchers', seabirds and raptor enthusiasts to name but a few. Messages can range from
3403-641: The auditory aspects of enjoying birds. In North America, many birders differentiate themselves from birdwatchers, and the term birder is unfamiliar to most lay people. At the most basic level, the distinction is perceived as one of dedication or intensity, though this is a subjective differentiation. Generally, self-described birders perceive themselves to be more versed in minutiae such as identification (aural and visual), molt, distribution, migration timing, and habitat usage. Whereas these dedicated birders may often travel specifically in search of birds, birdwatchers have been described by some enthusiasts as having
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3486-900: The 'scientification' of the pastime was 'undesirable'. This stand was to change only in 1936 when the RSPB was taken over by Tom Harrisson and others. Harrisson was instrumental in the organization of pioneering surveys of the great crested grebe . Increased mobility of birdwatchers ensured that books like Where to Watch Birds by John Gooders became best-sellers. By the 1960s air travel became feasible and long-distance holiday destinations opened up. By 1965, Britain's first birding tour company, Ornitholidays had been started by Lawrence Holloway. Travelling far away also led to problems in name usage: British birds such as "wheatear", "heron" and "swallow" needed adjectives to differentiate them in places where there were several related species. The falling cost of air travel made flying to remote birding destinations
3569-502: The Anglophone countries or Scandinavia. In the 20th century, most of the birding activity in North America was done on the east coast. The publication of Roger Tory Peterson's field guide in 1934 led to the initial increase in birding. Binoculars, an essential piece of birding equipment, became more easily available after World War II, making the hobby more accessible. The practice of travelling long distances to see rare bird species
3652-625: The Audubon Society, which was against the killing of birds, and the American Ornithologists' Union (AOU). The availability of first the bicycle and then the car increased the mobility of birdwatchers and this made new locations accessible. Networks of birdwatchers in the UK began to form in the late 1930s under the British Trust for Ornithology (BTO). The BTO saw the potential to produce scientific results through
3735-471: The U.S. Fish and Wildlife Service in 2016, over 45 million Americans consider themselves birders. North American birders were estimated to have spent as much as US$ 32 billion in 2001. The spending is on the rise around the world. Kuşcenneti National Park (KNP) at Lake Manyas, a Ramsar site in Turkey, was estimated to attract birders who spent as much as US$ 103,320,074 annually. Guided bird tours have become
3818-564: The US was Birds through an Opera Glass (1889) by Florence Bailey . Birding in North America was focused in the early and mid-20th century in the eastern seaboard region, and was influenced by the works of Ludlow Griscom and later Roger Tory Peterson . Bird Neighbors (1897) by Neltje Blanchan , an early birding book, sold over 250,000 copies. It was illustrated with color photographs of stuffed birds. The organization and networking of those interested in birds began through organizations like
3901-522: The US), probably has the most subscribers, followed by the English-language fork of Eurobirdnet , Birding-Aus from Australia, SABirdnet from South Africa and Orientalbirding. The increasing availability of mobile devices in the 2010s allowed the smartphone to become a useful tool for birding. Mobile apps can be used as replacements for physical birding field guides, such as the digital version of
3984-547: The United States of America. Since the second half of the 20th century an increasing number of people in developing countries have engaged in this activity, such as in the Degua Tembien district of Ethiopia. Transnational birding has played an important role in this, as birders in developing countries usually take up the pastime under the influence of foreign cultures with a history of birding. A majority of transnational birders are middle-aged, male, affluent, and belong to
4067-558: The ability to store and play large quantities of information, pocket-sized devices allow a full birding multimedia library to be taken into the field and mobile Internet access makes obtaining and transmitting information possible in near real time. New technologies are allowing birdwatching activities to take place over the Internet, using robotic camera installations and mobile phones set up in remote wildlife areas. Projects such as CONE [1] allow users to observe and photograph birds over
4150-426: The appearance of Maniraptoromorpha, the next 40 million years marked a continuous reduction of body size and the accumulation of neotenic (juvenile-like) characteristics. Hypercarnivory became increasingly less common while braincases enlarged and forelimbs became longer. The integument evolved into complex, pennaceous feathers . The oldest known paravian (and probably the earliest avialan) fossils come from
4233-437: The attractiveness of the breeding migration or roosting sites for birds, flush birds, and otherwise increase the pressure on birds and their habitats (e.g., luring birds out of their hideouts and stressing them by playing their calls or exposing birds and their nests to predators). Furthermore, other impacts include disturbance to birds, the environment, local cultures and the economy. Methods to reduce negative impact and improve
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#17327661274214316-485: The birds are more active and vocal making them easier to spot. Certain locations such as a local patch of forest, wetland and coast may be favoured according to the location and season. Seawatching , or pelagic birding, is a type of birding where observers based at a coastal watch point, such as a headland, watch birds flying over the sea. This is one form of pelagic birding, though birders also seek pelagic species from seagoing vessels. Weather plays an important role in
4399-507: The birds that descended from them. Despite being currently one of the most widely used, the crown-group definition of Aves has been criticised by some researchers. Lee and Spencer (1997) argued that, contrary to what Gauthier defended, this definition would not increase the stability of the clade and the exact content of Aves will always be uncertain because any defined clade (either crown or not) will have few synapomorphies distinguishing it from its closest relatives. Their alternative definition
4482-664: The earliest members of Aves, is removed from this group, becoming a non-avian dinosaur instead. These proposals have been adopted by many researchers in the field of palaeontology and bird evolution , though the exact definitions applied have been inconsistent. Avialae, initially proposed to replace the traditional fossil content of Aves, is often used synonymously with the vernacular term "bird" by these researchers. † Coelurus † Ornitholestes † Ornithomimosauria † Alvarezsauridae † Oviraptorosauria Paraves Most researchers define Avialae as branch-based clade, though definitions vary. Many authors have used
4565-450: The first avialans were omnivores . The Late Jurassic Archaeopteryx is well known as one of the first transitional fossils to be found, and it provided support for the theory of evolution in the late 19th century. Archaeopteryx was the first fossil to display both clearly traditional reptilian characteristics—teeth, clawed fingers, and a long, lizard-like tail—as well as wings with flight feathers similar to those of modern birds. It
4648-564: The growing trade in feathers in the United States while the Royal Society for the Protection of Birds began in Britain. The phrase "bird watching" appeared for the first time as the title of the book Bird Watching by Edmund Selous in 1901. In North America, the identification of birds, once thought possible only by shooting, was made possible by the emergence of optics and field identification guides. The earliest field guide in
4731-458: The hobby is an aspect of ornithology, coordinated in the UK by the British Trust for Ornithology . The Cornell Lab of Ornithology hosts many citizen-science projects to track the number and distribution of bird species across North America. These surveys help scientists note major changes from year to year which may occur as a result of climate change , disease, predation, and other factors. Because of their accessibility and ubiquity, birds are
4814-483: The late 1980s. The income level of birders has been found to be well above average. The Sibley Guide to Birds , published in 2000, had sold 500,000 copies by 2002. It was found that the number of birdwatchers rose, but there appeared to be a drop in birdwatching in the backyard. According to a U.S. Fish and Wildlife Service study, birders contributed $ 36 billion to the US economy in 2006, and one fifth (20%) of all Americans are identified as birdwatchers. According to
4897-563: The networks, unlike the Royal Society for the Protection of Birds (RSPB) which like the Audubon Society originated from the bird protection movement. Like the AOU in North America, the BOU had a focus mainly on collection-based taxonomy. The BOU changed focus to ecology and behaviour only in the 1940s. The BTO movement towards 'organized birdwatching' was opposed by the RSPB, which claimed that
4980-403: The numbers of birdwatchers increases, there is growing concern about the impact of birdwatching on the birds and their habitat. Birdwatching etiquette is evolving in response to this concern. Some examples of birdwatching etiquette include promoting the welfare of birds and their environment, limiting use of photography, pishing and playback devices to mitigate stress caused to birds, maintaining
5063-417: The occurrence of rare birds. In Britain, suitable wind conditions may lead to drift migration , and an influx of birds from the east. In North America, birds caught in the tail-end of a hurricane may be blown inland. Birders may take part in censuses of bird populations and migratory patterns which are sometimes specific to individual species. These birdwatchers may also count all birds in a given area, as in
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#17327661274215146-649: The only known exception of swine ) have brown adipose tissue whose mitochondria are capable of non-shivering thermogenesis . This process involves the direct dissipation of the mitochondrial gradient as heat via an uncoupling protein , thereby "uncoupling" the gradient from its usual function of driving ATP production via ATP synthase . In warm environments, these animals employ evaporative cooling to shed excess heat, either through sweating (some mammals) or by panting (many mammals and all birds)—mechanisms generally absent in poikilotherms. It has been hypothesized that warm-bloodedness evolved in mammals and birds as
5229-523: 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. The study of birds
5312-400: The outermost half) can be seen in the evolution of maniraptoromorphs, and this process culminated in the appearance of the pygostyle , an ossification of fused tail vertebrae. In the late Cretaceous, about 100 million years ago, the ancestors of all modern birds evolved a more open pelvis, allowing them to lay larger eggs compared to body size. Around 95 million years ago, they evolved
5395-443: The output than others. Like all energy conversions, metabolism is rather inefficient, and around 60% of the available energy is converted to heat rather than to ATP. In most organisms, this heat dissipates into the surroundings. However, endothermic homeotherms (generally referred to as "warm-blooded" animals) not only produce more heat but also possess superior means of retaining and regulating it compared to other animals. They exhibit
5478-514: The past three decades, investigations in the field of animal thermophysiology have unveiled numerous species within these two groups that do not meet all these criteria. For instance, many bats and small birds become poikilothermic and bradymetabolic during sleep (or, in nocturnal species, during the day). For such creatures, the term heterothermy was introduced. Further examinations of animals traditionally classified as cold-blooded have revealed that most creatures manifest varying combinations of
5561-432: The person who watches birds for any reason at all, and should not be used to refer to the serious birder. Twitching is a British term used to mean "the pursuit of a previously located rare bird." In North America, it is more often called chasing . The term twitcher , sometimes misapplied as a synonym for birder , is reserved for those who travel long distances to see a rare bird that would then be ticked , or counted on
5644-410: The places they visit. In addition to this, birdwatching tourism is considered a niche market of nature-based tourism. Birdwatching and other niche tourism markets are good for market diversification and mitigating the impacts of seasonality in a tourism market as well as bringing economic resources to remote communities, thus diversifying their economies and contributing to biodiversity conservation. It
5727-532: The previously clear distinction between non-birds and birds has become blurred. By the 2000s, discoveries in the Liaoning Province of northeast China, which demonstrated many small theropod feathered dinosaurs , contributed to this ambiguity. The consensus view in contemporary palaeontology is that the flying theropods, or avialans , are the closest relatives of the deinonychosaurs , which include dromaeosaurids and troodontids . Together, these form
5810-518: The radio in Eric Simms' Countryside program but this did not catch on. In the 1960s people began using the telephone and some people became hubs for communication. In the 1970s some cafés, such as that in Cley, Norfolk run by Nancy Gull, became centers for meeting and communication. This was replaced by telephone hotline services such as "Birdline" and "Bird Information Service". With the advent of
5893-536: The required recordings much more flexible than tape-based models. It is now possible to take a recording of every bird call you are likely to encounter in a given area out into the field stored on a device that will slip into your pocket and to retrieve calls for playback and comparison in any order you choose. As the technology continues to improve, researchers and hobby birders have started using convolutional neural networks to mine sound recordings to identify and track specific bird calls. Photography has always been
5976-449: The same biological name "Aves", which is a problem. The authors proposed to reserve the term Aves only for the crown group consisting of the last common ancestor of all living birds and all of its descendants, which corresponds to meaning number 4 below. They assigned other names to the other groups. Lizards & snakes Turtles Crocodiles Birds Under the fourth definition Archaeopteryx , traditionally considered one of
6059-549: The second toe which may have been held clear of the ground in life, and long feathers or "hind wings" covering the hind limbs and feet, which may have been used in aerial maneuvering. Avialans diversified into a wide variety of forms during the Cretaceous period. Many groups retained primitive characteristics , such as clawed wings and teeth, though the latter were lost independently in a number of avialan groups, including modern birds (Aves). Increasingly stiff tails (especially
6142-416: The serious to trivial, notifying others of rarities, questioning the taxonomy or identification of a species, discussing field guides and other resources, asking for advice and guidance, or organizing groups to help save habitats. Occasional postings are mentioned in academic journals and therefore can be a valuable resource for professional and amateur birders alike. One of the oldest, Birdchat (based in
6225-560: The study of birds using formal scientific methods. The first recorded use of the term birdwatcher was in 1712 by William Oldsworth. The term birding was also used for the practice of fowling or hunting with firearms as in Shakespeare 's The Merry Wives of Windsor (1602): "She laments sir... her husband goes this morning a-birding." The terms birding and birdwatching are today used by some interchangeably, although some participants prefer birding , partly because it includes
6308-404: The terms warm-blooded and cold-blooded have been deprecated in the scientific field. In general, warm-bloodedness refers to three separate categories of thermoregulation . A significant proportion of creatures commonly referred to as "warm-blooded," like birds and mammals, exhibit all three of these categories (i.e., they are endothermic, homeothermic, and tachymetabolic). However, over
6391-555: The three aforementioned terms, along with their counterparts (ectothermy, poikilothermy, and bradymetabolism), thus creating a broad spectrum of body temperature types. Some fish have warm-blooded characteristics, such as the opah . Swordfish and some sharks have circulatory mechanisms that keep their brains and eyes above ambient temperatures and thus increase their ability to detect and react to prey . Tunas and some sharks have similar mechanisms in their muscles, improving their stamina when swimming at high speed. Body heat
6474-517: The value of conservation are the subject of research. Many birders occupy themselves with observing local species (birding in their "local patch" ), but may also make specific trips to observe birds in other locales. The most active times of the year for birding in temperate zones are during the spring or fall migrations when the greatest variety of birds may be seen. On these occasions, large numbers of birds travel north or south to wintering or nesting locations. Early mornings are typically better as
6557-405: The visual characteristics of a bird, but also its patterns of movement and its sound, has wide applications for birders in the field. This class of product includes devices that can play (and in some cases record) a range of digital media, typically video, audio and still image files. Many modern digital cameras , mobile phones , and camcorders can be classified as portable media players . With
6640-473: The web; similarly, robotic cameras set up in largely inhospitable areas are being used to attempt the first photographs of the rare ivory-billed woodpecker . These systems represent new technologies in the birdwatcher's toolkit. In the early 1950s, the only way of communicating new bird sightings was through the postal system and it was generally too late for the recipients to act on the information. In 1953 James Ferguson-Lees began broadcasting rare bird news on
6723-420: Was aided by the availability of cars and their associated infrastructure. Nevertheless, distance to urban centres may still affect number of birdwatchers participating in observations of rare bird species. About 4% of North Americans were interested in birding in the 1970s, and in the mid-1980s at least 11% were found to watch birds at least 20 days of the year. The number of birders was estimated at 61 million in
6806-462: Was developed by Francis Willughby and John Ray in their 1676 volume Ornithologiae . Carl Linnaeus modified that work in 1758 to devise the taxonomic classification system currently in use. Birds are categorised as the biological class Aves in Linnaean taxonomy . Phylogenetic taxonomy places Aves in the clade Theropoda as an infraclass or a subclass, more recently a subclass. Aves and
6889-422: Was originally started as a club for "listers", but it now serves a much broader audience. Still, the ABA continues to publish an official annual report of North American list standings. Competitive birdwatching events include: Prominent national and continental organizations concerned with birding include the British Trust for Ornithology and Royal Society for the Protection of Birds in the United Kingdom, and
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