71-526: The brown thrasher ( Toxostoma rufum ), sometimes erroneously called the brown thrush or fox-coloured thrush , is a bird in the family Mimidae , which also includes the New World catbirds and mockingbirds . The brown thrasher is abundant throughout the eastern and central United States and southern and central Canada , and it is the only thrasher to live primarily east of the Rockies and central Texas . It
142-616: A Tcheh sound in the beginning that ends with an eeeur , kakaka , and sounds reminiscent of a stick scraping a concrete sidewalk. Brown thrashers are noted for their mimicry (as a member of the family Mimidae ), but they are not as diverse in this category as their relative the northern mockingbird . However, during the breeding season, the mimicking ability of the male is at its best display, impersonating sounds from tufted titmice ( Baeolophus bicolor ), northern cardinals ( Cardinalis cardinalis ), wood thrushes, northern flickers ( Colaptes auratus ), among other species. Although this bird
213-772: 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 Long-billed thrasher Orpheus longirostris The long-billed thrasher ( Toxostoma longirostre )
284-400: A blueish or greenish tint along with reddish-brown spots. There are rare occurrences of no spots on the eggs. The nest is built twiggy, lined with grass, leaves, and other forms of dead vegetation. The nests are typically built in a dense shrub or low in a tree, usually up to 2.1 m (6.9 ft) high, but have built nests as high as 6 m (20 ft). They also on occasion build nests on
355-473: 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
426-442: 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
497-520: A pale-buffy white, although the chest and belly contain keenly blackish oval shapes. The underwing is buffy-white. The iris is typically either orange or orange-yellow, with a dull brown bill with its base of the lower mandible appear to be pinkish grey. T. longirostre ssp. longirostre is similar with an exception to being smaller, darker, and has a red-tinged appearance with buffy-white underparts. Juveniles have dusty streak marks on its rump, with buffy-white undertail coverts. This thrasher shares
568-406: 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
639-441: A striking resemblance with the brown thrasher. However, there are a number of differences. Its face is more gray in contrast to the reddish appearance of the thrasher. The underparts are whiter, less buffy, and more robustly colored, an eye that appears more orange and beady, and generally a longer-bill that is blacker and stands apart from the face. The long-billed's overall appearance has more contrasts in its pattern in comparison to
710-717: 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)
781-493: A time. By the fall, the male sings with smoother sub-songs. During the winter, the males may also sing in short spurts during altercations with neighboring males. In the birds' youth, alarm noises are the sounds made. As an adult, the brown thrasher has an array of sounds it will make in various situations. Both male and females make smack and teeooo -like alarm calls when provoked, and hijjj sounds at dusk and dawn. Others calls may consist of an acute, sudden chakk , rrrrr ,
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#1732851206678852-414: Is 25% greater in dry leaf litter as compared to damp leaf letter. The brown thrasher can also hammer nuts such as acorns in order to remove the shell. It has also been noted for its flexibility in catching quick insects, as the amount of vertebrae in its neck exceeds giraffes and camels. In one case, a brown thrasher was observed to dig a hole about 1.5 cm (0.59 in) deep, place an acorn in it and hit
923-520: Is a large-sized thrasher that is close in size to the American robin . T. longirostre ssp. sennitti is described with a grayish-brown crown with a rufous color appearing in the back, rump, rear, and shoulder. Broad white tips located on the greater and lesser primary coverts and dullish-brown with rufous brown edges on the primary and secondary coverts gives the closed wings a rufous appearance. The chin, throat, chest, and belly can appear to be white or
994-405: Is a medium-sized resident songbird of South Texas and eastern Mexico . It bears a strong resemblance to its close relative the brown thrasher in appearance, calls, and various other behaviors; however, the two species do not overlap in range except in the winter when the brown thrasher will temporarily reside in the northern range of the long-billed. The bird is a large sized mimid that
1065-492: Is at the highest among the Rio Grande Valley . Although it is a resident in the lower Rio Grande Valley, a significant amount of its habitat was destroyed for agricultural purposes, and its population in the area decreased from the 1930s to the 1970s. Some human activity that has introduced appropriate habitat is thought to have been some help the species, and it is still is a common resident within its range. In Texas there
1136-533: 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
1207-469: Is generally moderate in size for a thrasher, being distinctly larger than the sage thrasher ( Oreoscoptes montanus ) but similar or somewhat smaller in size than the more brownish Toxostoma species found further west. Adults measure around 23.5 to 30.5 cm (9.3 to 12.0 in) long with a wingspan of 29 to 33 cm (11 to 13 in), and weigh 61 to 89 g (2.2 to 3.1 oz), with an average of 68 g (2.4 oz). Among standard measurements,
1278-429: 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
1349-565: Is less likely to live near housing than other bird species. The brown thrasher often vies for habitat and potential nesting grounds with other birds, which is usually initiated by the males. The brown thrasher is a strong, but partial migrant, as the bird is a year-round resident in the southern portion of its range. The breeding range includes the United States and Canada east of the Rocky Mountains, but has been occasionally spotted West of
1420-503: 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
1491-466: Is not especially wary, but it will take precautionary measures to prevent itself from being potential prey. Like other thrashers, it is named after its sweeping methods when searching for food, not for thrashing predators, although they are aggressive defenders of their territories. The specific name longirostre is derived from the Latin words longus long and rostrum bill. There are two subspecies of
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#17328512066781562-411: Is rounded with paler corners, and eyes are a brilliant yellow. Its bill is brownish, long, and curves downward. Both male and females are similar in appearance. The juvenile appearance of the brown thrasher from the adult is not remarkably different, except for plumage texture, indiscreet upper part markings, and the irises having an olive color. The brown thrasher is a fairly large passerine, although it
1633-470: Is some evidence of a northern and eastern expansion of the range over a five decade span (1957-2007), with climate change as the suggested cause. With the exception of vagrants found in New Mexico and Colorado , the species is a permanent resident of its range. Long-billed thrashers usually stay hidden on or near the ground, though it may sing from conspicuous perches. Whenever it searches for insects on
1704-516: 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,
1775-606: Is the state bird of Georgia . The brown thrasher also was the inspiration for the name of Atlanta 's former National Hockey League team, the Atlanta Thrashers , who relocated in 2011 to become the current Winnipeg Jets (the original Jets relocated to Phoenix in 1996 to become the Coyotes ). Bird Birds are a group of warm-blooded vertebrates constituting the class Aves ( Latin: [ˈaveːs] ), characterised by feathers , toothless beaked jaws,
1846-443: Is the state bird of Georgia . As a member of the genus Toxostoma , the bird is relatively large-sized among the other thrashers . It has brown upper parts with a white under part with dark streaks. Because of this, it is often confused with the smaller wood thrush ( Hylocichla mustelina ), among other species. The brown thrasher is noted for having over 1000 song types, and the largest song repertoire of birds. However, each note
1917-530: 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
1988-419: Is usually an elusive bird, and maintains its evasiveness with low-level flying. When it feels bothered, it usually hides into thickets and gives cackling calls. Thrashers spend most of their time on ground level or near it. When seen, it is commonly the males that are singing from unadorned branches. The brown thrasher has been noted for having an aggressive behavior, and is a staunch defender of its nest. However,
2059-543: Is usually repeated in two or three phrases. The brown thrasher is an omnivore, with its diet ranging from insects to fruits and nuts. The usual nesting areas are shrubs, small trees, or at times on ground level. Brown thrashers are generally inconspicuous but territorial birds, especially when defending their nests, and will attack species as large as humans. The brown thrasher was originally described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae as Turdus rufus . The genus name Toxostoma comes from
2130-455: Is warbling and resembles other thrashers ' songs but is especially rich and musical, though occasionally scratchy. Phrases are often repeated two to four times. A distinctive call is a "loud, rich whistle cleeooeep " or "mellow, whistled tweeooip or ooeh "; other calls include "a loud sharp chak " and "a very rapid, sharp rattle chtttr ", and tsuck and verrs sounds during territorial disputes that resemble calls of its close relative
2201-411: Is widespread and still common, it has declined in numbers in some areas due to loss of suitable habitat . Despite the decrease, the rate does not warrant a status towards vulnerable . One of the natural nuisances is the parasitic brown-headed cowbird ( Molothrus ater ), but these incidents are rare. Whenever these situations occur, the brown thrashers usually discard of the cowbirds' eggs. Occasionally,
Brown thrasher - Misplaced Pages Continue
2272-526: The Ancient Greek toxon , "bow" or "arch" and stoma , "mouth". The specific rufum is Latin for "red", but covers a wider range of hues than the English term. Although not in the thrush family, this bird is sometimes erroneously called the brown thrush. The name misconception could be because the word thrasher is believed to derive from the word thrush . The naturalist Mark Catesby called it
2343-715: 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
2414-535: The Rio Grande Valley and the Mexican states of Tamaulipas and San Luis Potosi . Along with the brown thrasher and Cozumel thrasher , the three are part of a superspecies rufum clade . Plumage patterns and bill shapes were originally used for grouping, and the birds also were shown as closely related with genetic studies. This bird is slender and long-tailed, averaging 26.5–29 cm (10.5–11.5 in) in length and about 70 g (2.5 oz) in weight. It
2485-660: 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
2556-476: 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;
2627-457: The wing chord is 9.5 to 11.5 cm (3.7 to 4.5 in), the tail is 10.9 to 14.1 cm (4.3 to 5.6 in), the culmen is 2.2 to 2.9 cm (0.87 to 1.14 in) and the tarsus is 3.2 to 3.6 cm (1.3 to 1.4 in). There are two subspecies: the 'brown thrasher' ( T. rufum rufum ), which lies in the eastern half of Canada and the United States, and the 'western brown thrasher' ( T. rufum longicauda (Baird, 1858)), which resides in
2698-636: The Rockies. The increase in trees throughout the Great Plains during the past century due to fire suppression and tree planting facilitated a westward range expansion of the brown thrasher as well as range expansions of many other species of birds. Studies indicate that thrashers that reside in the New England region of the United States during the breeding season fly toward the Carolinas and Georgia, birds located in
2769-464: The acorn until it cracked, considered to be a form of tool usage. In a laboratory experiment, a brown thrasher was found to be able to discern and reject the toxic eastern newt ( Notophthalmus viridescens ) and a palatable mimic of that species, the red salamander ( Pseudotriton ruber ), but continued to eat palatable dusky salamanders ( Desmognathus spp.). Brown thrashers are typically monogamous birds, but mate-switching does occur, at times during
2840-579: The appearance is indistinguishable from the brown thrasher. Most of the egg laying for the long-billed in Texas occurs in April and May, and May and June in Mexico, though dates have been as late as June and July, respectively. The eggs hatch over a period of 24 days. Unlike most thrashers, however, the hatching process is synchronous. Both parents are responsible for incubation , which lasts 13 or 14 days as well as feeding
2911-428: 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
Brown thrasher - Misplaced Pages Continue
2982-509: 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
3053-409: The brown thrasher. The sage thrasher , which shares some its distribution with the long-billed, is smaller, grayer, and its rectrices are of a more distinguished white color. This species is a resident in southern Texas north to San Antonio and Aranas , south through north-western Mexico to central Veracruz , east to eastern Coahuila , San Luis Potosi and Hildalgo . The breeding density
3124-526: The brown thrasher. The general nesting habitat of long-billed thrashers is amongst dense vegetation with spiny shrubs and trees in order to make the nest inaccessible to potential predators. Nests have also been found in plants such as willows , mesquite , huisache , cacti , or yucca . The nest is a bulky cup placed in thick low or mid-height vegetation and made of materials such as twigs, straws, and grasses. The female lays 2 to 5 eggs described as bluish-white with dense reddish-brown and gray speckles;
3195-816: The catbird, snakes , birds of prey , and cats are among the top predators of the thrasher. In Kansas , at least eight species of snake were identified as potentially serious sources of nest failure. Among the identified avian predators of adults are Cooper's hawks ( Accipiter cooperii ), northern goshawk ( Accipiter gentilis ), broad-winged hawks ( Buteo platypterus ), merlins ( Falco columbarius ), peregrine falcons ( Falco peregrinus ), eastern screech-owls ( Megascops asio ), great horned owls ( Bubo virginianus ) barred owls ( Strix varia ) and long-eared owls ( Asio otus ). The brown thrasher methods of defending itself include using its bill, which can inflict significant damage to species smaller than it, along with wing-flapping and vocal expressions. The brown thrasher
3266-494: The central United States east of the Rocky Mountains and southern central Canada. The western brown thrasher is distinguished by a more cinnamon upper part, whiter wing bars, and darker breast spots than T.rufum rufum . The lifespan of the brown thrasher varies on a year-to-year basis, as the rate of survival the first year is 35%, 50% in between the second and third year, and 75% between the third and fourth year. Disease and exposure to cold weather are among contributing factors for
3337-418: The dry period when food supply is generally lower, 80% of the food became animal and only 20% plants. Vertebrates are only eaten occasionally and are often comprised by small reptiles and amphibians , such as lizards , small or young snakes , tree frogs and salamanders . The brown thrasher utilizes its vision while scouring for food. It usually forages for food under leaves, brushes, and soil debris on
3408-665: 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
3479-618: The east of the Mississippi winter from Arkansas to Georgia, and birds located in the Dakotas and the central Canadian provinces head towards eastern Texas and Louisiana . When the species does migrate, it is typically for short distances and during the night. There are also records of the bird wintering in Mexico , as well as a British record of a transatlantic vagrant. The brown thrasher has been observed either solo or in pairs. The brown thrasher
3550-457: The exchanging of probable nesting material. Males will sing gentler as they sight a female, and this enacts the female to grab a twig or leaf and present it to the male, with flapping wings and chirping sounds. The males might also present a gift in response and approach the female. Both sexes will take part in nest building once mates find each other, and will mate after the nest is completed. The female lays 3 to 5 eggs , that usually appears with
3621-451: 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
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#17328512066783692-424: The fox-coloured thrush. Genetic studies have found that the brown thrasher is most closely related to the long-billed and Cozumel thrashers ( T. longirostre & guttatum ), within the genus Toxostoma . The brown thrasher is bright reddish-brown above with thin, dark streaks on its buffy underparts. It has a whitish-colored chest with distinguished teardrop-shaped markings on its chest. Its long, rufous tail
3763-436: The ground using its bill. It then swipes the floor in side-to-side motions, and investigates the area it recently foraged in. The brown thrasher forages in a similar method to the long-billed thrasher and Bendire's thrasher ( T. longirostre & bendirei ), picking food off the ground and under leaf litter , whereas thrashers with sharply decurved bills are more likely to dig into the ground to obtain food. Foraging success
3834-401: The ground, it will energetically turn over ("thrashing") leaves and other litter. It also can be spotted singing on exposed perches above its thornbush fortresses. Males generally are spotted singing from March until the mid-summer, excluding instances of singing song snatches periodically to balance the year. It is generally not wary, possibly because is not easily approached. The flights of
3905-431: The ground. Between eleven days to two weeks, the eggs hatch. Both parents incubate and feed the young, with the female doing most of the incubating. Nine to thirteen days after hatching, the nestlings begin to fledge . These birds raise two, sometimes even three, broods in a year. The male sings a series of short repeated melodious phrases from an open perch to declare his territory, and is also very aggressive in defending
3976-552: The late summer, it begins to shift towards more of a herbivore diet, focusing on fruits , nuts , seeds , and grains , 60% of the food in Illinois being fruits and seeds. By winter, the customary diet of the brown thrasher is fruit and acorns . Wintering birds in Texas were found to eat 58% plant material (mainly sugar berry and poison ivy ) and 42% animal material in October; by March, in
4047-423: The limits of the lifespan. However, the longest lived thrasher in the wild is 12 years, and relatively the same for ones in captivity. The similar-looking long-billed thrasher has a significantly smaller range. It has a gray head and neck, and has a longer bill than the brown thrasher. The brown thrasher's appearance is also strikingly similar to the wood thrush , the bird that it is usually mistaken for. However,
4118-464: The long-billed are generally close to the ground, short, erratic with exaggerated fluctuations. Long-billed thrashers are staunch defenders of their territories; it will defend its nest ferociously, including against humans. The longest recorded lifespan of the species was one individual recovered on 30 September 1965, at age 7 years and 3 months, after being banded (on 24 Aug 1959) in Alamo, TX. The song
4189-586: The long-billed thrasher. T. longirostre ssp. longirostre was first described in scientific literature by Frédéric de Lafresnaye in 1838 as Orpheus longirostris , while T. longirostre ssp. sennitti was described by Robert Ridgway a half-century later. T. longirostre ssp. longirostre (Lafresnaye, 1838). Range is in eastern Mexico, within the states of Querétaro , Tamaulipas and Veracruz southward to Puebla . T. longirostre ssp. sennitti (Ridgway, 1888), known as Sennett's thrasher. Range extends from southern (particularly south central) Texas to
4260-517: The name does not come from attacking perceived threats, but is believed to have come from the thrashing sound the bird makes when digging through ground debris. It is also thought that the name comes from the thrashing sound that is made while it is smashing large insects to kill and eventually eat. This bird is omnivorous , which has a diet that includes insects , berries , nuts and seeds , as well as earthworms , snails , and sometimes lizards and frogs . Across seasons and its breeding range, it
4331-517: The nest, known to strike people and animals. The male brown thrasher may have the largest song repertoire of any North American bird, which has been documented as at least over 1,100 songs. Some sources state that each individual has up to 3,000 song phrases, while others put the number beyond 3,000. The males' singing voice usually contains more of a melodic tone than that of the related grey catbird . Its song are coherent phrases that are iterated no more than three times, but has been done for minutes at
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#17328512066784402-523: 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
4473-402: 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
4544-528: 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
4615-452: 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
4686-580: The same season. Their breeding season varies by region. In the southeastern United States , the breeding months begin in February and March, while May and June see the commencement of breeding in the northern portion of their breeding range. When males enter the breeding grounds, their territory can range from 2 to 10 acres (0.81 to 4.05 ha). Around this time of the year the males are usually at their most active, singing loudly to attract potential mates, and are found on top of perches. The courting ritual involves
4757-545: 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
4828-622: The thrasher has thrown out their own eggs instead of the cowbird eggs due to similar egg size, and at least one recorded event raised a fledgling. Northern cardinals and grey catbirds are also major competitors for thrashers in terms of territorial gain. Because of the apparent lack of opportunistic behavior around species like these, thrashers are prone to be driven out of zones for territory competition. Brown thrashers have tendencies to double-brood or have failures on their first nesting attempts due to predation. Grey catbirds have been seen invading brown thrashers' nests and breaking their eggs. Other than
4899-485: The wood thrush has dark rounded spots on its under parts rather than the brown thrashers' elongated streaks, has dark eyes, shorter tail, a shorter, straighter bill (with the head generally more typical of a thrush), and is a smaller bird. The brown thrasher resides in various habitats. It prefers to live in woodland edges, thickets and dense brush, often searching for food in dry leaves on the ground. It can also inhabit areas that are agricultural and near suburban areas, but
4970-461: 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
5041-437: Was found 63% of stomach contents were made of animal matter, the remaining 37% being plant material. During the breeding season, the diet consists primarily of beetles , grasshoppers , and other arthropods , and fruits , nuts and seeds . More than 80% of the diet of brown thrasher from Illinois is made of animal matter, about 50% being beetles. In Iowa , about 20% of the summer diet was found to consist of grasshoppers. By
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