Catharus
Encyclopedia
Catharus is a genus
of bird
s in the thrush
family Turdidae. It contains the small, mostly insectivorous or omnivorous migrant
thrushes of North America
and the nightingale-thrushes of Central
and South America
. Its closest relative is the Wood Thrush
of the monotypic
genus Hylocichla (Winker & Pruett, 2006) which is sometimes merged into Catharus.
These are mainly forest
birds with large eyes, straight slim bills
and fluty voices.
This is a typical New World thrush genus, although representatives of other genera, such as the true thrush
es (Turdus) also occur in the region, especially in Central
and South America
. The breeding range
of one species, Grey-cheeked Thrush, extends into Siberia
. The four North America
n species have all been recorded as vagrants in Europe
on multiple occasions, and Swainson's
and Hermit Thrush
es have occurred as vagrants in northeast Asia.
characters, the migrant group occasionally including the Wood Thrush also. Comparison of mtDNA cytochrome b
and NADH dehydrogenase
subunit
2 as well as nuclear
β-fibrinogen
intron
7 sequence
data indicates that this is incorrect (Winker & Pruett, 2006).
Due to the adaptation
al requirements of the independently acquired long-distance migrant lifestyle, several apparent morphological similarities between supposedly related species are actually due to convergent evolution
. It seems that the genus originated in tropical or subtropical forest ecosystem
s of northern Central America, and that every so often species diverged to settle more northerly regions, subsequently finding themselves forced to migrate south in winter into more food-rich habitat. The most ancient of these northward divergences was probably Swainson's Thrush
, and the most recent one the fuscescens-minimus-bicknelli cryptic species complex
.
The nightingale-thrushes are also paraphyletic. Whereas the aurantiirostris-fuscater/mexicanus-dryas group indeed forms a distinct lineage – probably living close to the genus' center of origin – the Russet Nightingale-thrush is closest to the Hermit Thrush. The Ruddy-capped Nightingale-thrush is close to the Gray-cheeked species complex, while the Black-billed Nightingale-thrush is also fairly close to both of the nightingale-thrush/migrant lineages. Swainson's Thrush has no close living relatives.
The species are:
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s in the thrush
Thrush (bird)
The thrushes, family Turdidae, are a group of passerine birds that occur worldwide.-Characteristics:Thrushes are plump, soft-plumaged, small to medium-sized birds, inhabiting wooded areas, and often feed on the ground or eat small fruit. The smallest thrush may be the Forest Rock-thrush, at and...
family Turdidae. It contains the small, mostly insectivorous or omnivorous migrant
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
thrushes of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and the nightingale-thrushes of Central
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. Its closest relative is the Wood Thrush
Wood Thrush
The Wood Thrush, Hylocichla mustelina, is a North American passerine bird. It is closely related to other thrushes such as the American Robin and is widely distributed across North America, wintering in Central America and southern Mexico...
of the monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
genus Hylocichla (Winker & Pruett, 2006) which is sometimes merged into Catharus.
These are mainly forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
birds with large eyes, straight slim bills
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
and fluty voices.
This is a typical New World thrush genus, although representatives of other genera, such as the true thrush
True thrush
The true thrushes are medium-sized mostly insectivorous or omnivorous birds in the genus Turdus of the thrush family Turdidae.The genus has a cosmopolitan distribution, with species in the Americas, Europe, Asia, Africa and Australia. Several species have also colonised some oceanic islands, and...
es (Turdus) also occur in the region, especially in Central
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. The breeding range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
of one species, Grey-cheeked Thrush, extends into Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
. The four North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n species have all been recorded as vagrants in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
on multiple occasions, and Swainson's
Swainson's Thrush
Swainson's Thrush , also called Olive-backed Thrush, is a medium-sized thrush. This species is 16–18 cm in length, and has the white-dark-white underwing pattern characteristic of Catharus thrushes...
and Hermit Thrush
Hermit Thrush
The Hermit Thrush is a medium-sized North American thrush. It is not very closely related to the other North American migrant species of Catharus, but rather to the Mexican Russet Nightingale-thrush.-Description:...
es have occurred as vagrants in northeast Asia.
Systematics
The Catharus species are either long-distance migrants or fairly resident birds. They were sometimes split according to this and morphologicalMorphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
characters, the migrant group occasionally including the Wood Thrush also. Comparison of mtDNA cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
and NADH dehydrogenase
NADH dehydrogenase
NADH dehydrogenase is an enzyme located in the inner mitochondrial membrane that catalyzes the transfer of electrons from NADH to coenzyme Q...
subunit
Protein subunit
In structural biology, a protein subunit or subunit protein is a single protein molecule that assembles with other protein molecules to form a protein complex: a multimeric or oligomeric protein. Many naturally occurring proteins and enzymes are multimeric...
2 as well as nuclear
Nuclear DNA
Nuclear DNA, nuclear deoxyribonucleic acid , is DNA contained within a nucleus of eukaryotic organisms. In mammals and vertebrates, nuclear DNA encodes more of the genome than the mitochondrial DNA and is composed of information inherited from two parents, one male, and one female, rather than...
β-fibrinogen
Fibrinogen
Fibrinogen is a soluble plasma glycoprotein, synthesised by the liver, that is converted by thrombin into fibrin during blood coagulation. This is achieved through processes in the coagulation cascade that activate the zymogen prothrombin to the serine protease thrombin, which is responsible for...
intron
Intron
An intron is any nucleotide sequence within a gene that is removed by RNA splicing to generate the final mature RNA product of a gene. The term intron refers to both the DNA sequence within a gene, and the corresponding sequence in RNA transcripts. Sequences that are joined together in the final...
7 sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
data indicates that this is incorrect (Winker & Pruett, 2006).
Due to the adaptation
Adaptation
An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation....
al requirements of the independently acquired long-distance migrant lifestyle, several apparent morphological similarities between supposedly related species are actually due to convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
. It seems that the genus originated in tropical or subtropical forest ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s of northern Central America, and that every so often species diverged to settle more northerly regions, subsequently finding themselves forced to migrate south in winter into more food-rich habitat. The most ancient of these northward divergences was probably Swainson's Thrush
Swainson's Thrush
Swainson's Thrush , also called Olive-backed Thrush, is a medium-sized thrush. This species is 16–18 cm in length, and has the white-dark-white underwing pattern characteristic of Catharus thrushes...
, and the most recent one the fuscescens-minimus-bicknelli cryptic species complex
Cryptic species complex
In biology, a cryptic species complex is a group of species which satisfy the biological definition of species—that is, they are reproductively isolated from each other—but whose morphology is very similar ....
.
The nightingale-thrushes are also paraphyletic. Whereas the aurantiirostris-fuscater/mexicanus-dryas group indeed forms a distinct lineage – probably living close to the genus' center of origin – the Russet Nightingale-thrush is closest to the Hermit Thrush. The Ruddy-capped Nightingale-thrush is close to the Gray-cheeked species complex, while the Black-billed Nightingale-thrush is also fairly close to both of the nightingale-thrush/migrant lineages. Swainson's Thrush has no close living relatives.
The species are:
- VeeryVeeryThe Veery, Catharus fuscescens, is a small thrush species. It is occasionally called Willow Thrush or Wilson's Thrush. It is a member of a close-knit group of migrant Catharus species, which also includes the cryptotaxa Grey-cheeked Thrush and Bicknell's Thrush The Veery, Catharus fuscescens, is a...
, Willow Thrush or Wilson's Thrush, Catharus fuscescens - Gray-cheeked ThrushGray-cheeked ThrushThe Grey-cheeked Thrush, Catharus minimus, is a medium-sized thrush. This species is 15–17 cm in length, and has the white-dark-white underwing pattern characteristic of Catharus thrushes. It is a member of a close-knit group of migrant species together with the Veery and Bicknell's Thrush ;...
, Catharus minimus - Bicknell's ThrushBicknell's ThrushThe Bicknell's Thrush, Catharus bicknelli, is a medium-sized thrush, at 17.5 cm and 28 g . It was named after Eugene Bicknell, an American amateur ornithologist, who discovered the species on Slide Mountain in the Catskills in the late 19th century.Adults are olive-brown on the upperparts,...
, Catharus bicknelli
- Ruddy-capped Nightingale-thrushRuddy-capped Nightingale-thrushThe Ruddy-capped Nightingale-thrush is a small thrush which is a resident breeder in mountain forests from central Mexico to western Panama. A predominantly brown-plumaged bird, it has a rich song.-Taxonomy and naming:...
, Catharus frantzii
- Black-billed Nightingale-thrushBlack-billed Nightingale-thrushThe Black-billed Nightingale-thrush is a small thrush endemic to the highlands of Costa Rica and western Panama. Its position in the genus Catharus is somewhat equivocal, but it is apparently closer to the Hermit Thrush than to the other nightingale-thrushes except the Russet Nightingale-thrush...
, Catharus gracilirostris
- Hermit ThrushHermit ThrushThe Hermit Thrush is a medium-sized North American thrush. It is not very closely related to the other North American migrant species of Catharus, but rather to the Mexican Russet Nightingale-thrush.-Description:...
, Catharus guttatus - Russet Nightingale-thrushRusset Nightingale-thrushThe Russet Nightingale-thrush is a species of bird in the Turdidae family.It is endemic to Mexico.Its natural habitat is subtropical or tropical moist montanes.-Description:...
, Catharus occidentalis
- Swainson's ThrushSwainson's ThrushSwainson's Thrush , also called Olive-backed Thrush, is a medium-sized thrush. This species is 16–18 cm in length, and has the white-dark-white underwing pattern characteristic of Catharus thrushes...
or Olive-backed Thrush, Catharus ustulatus
- Orange-billed Nightingale-thrushOrange-billed Nightingale-thrushThe Orange-billed Nightingale-thrush is a species of bird in the Turdidae family.It is found in Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Trinidad and Tobago, and Venezuela....
, Catharus aurantiirostris - Slaty-backed Nightingale-thrushSlaty-backed Nightingale-thrushThe Slaty-backed Nightingale-thrush is a species of bird in the Turdidae family.It is found in Bolivia, Colombia, Costa Rica, Ecuador, Panama, Peru, and Venezuela....
, Catharus fuscater - Black-headed Nightingale-thrushBlack-headed Nightingale-thrushThe Black-headed Nightingale-thrush is a species of bird in the Turdidae family. It is found in Costa Rica, Guatemala, Honduras, Mexico, Nicaragua, and Panama....
, Catharus mexicanus - Spotted Nightingale-thrushSpotted Nightingale-thrushThe Spotted Nightingale-thrush is a species of bird in the Turdidae family.It is found in Argentina, Bolivia, Colombia, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Peru, and Venezuela....
, Catharus dryas