Cracidae
Encyclopedia
The chachalacas, guans and curassows are bird
s in the family
Cracidae.
These are species of tropical and subtropical Central
and South America
. One species, the Plain Chachalaca
, just reaches southernmost Texas
in the USA
. Two species, the Trinidad Piping Guan and the Rufous-vented Chachalaca
occur on the islands of Trinidad and Tobago
respectively.
. The guans and curassows live in trees, but the smaller chachalacas are found in more open scrubby habitats. Many species are fairly long tailed, which may be an aide to navigating their largely arboreal existence. They are generally dull-plumaged, but the curassows and some guans have colourful facial ornaments. The birds are particular vocal, with the chachalacas taking their name from the sound of their call. Cracids range in size from the Little Chachalaca
(Ortalis motmot), at as little as 38 cm (15 in) and 350 g (12.5 oz), to the Great Curassow
(Crax rubra), at nearly 1 m (40 in) and 4.3 kg (9.5 lbs).
These species feed on fruit, insects and worms. They build nests in trees, and lay two to three large white eggs
, which only the female incubates alone. The young are precocial
and are born with an instinct to immediately climb and seek refuge in the nesting tree. They are able to fly within days of hatching.
n Mound-builders
. They are sometimes united with these in a distinct order
, "Craciformes", but this is not supported by more recent research which suggests that either is a well-marked, basal
lineage of Galliformes
.
FAMILY: CRACIDAE
Subfamily N.N.
Alternatively, all subfamilies except the Penelopinae could be lumped into the Cracinae. As the initial radiation of cracids is not well resolved at present (see below), the system used here seems more appropriate. It is also quite probable that entirely extinct subfamilies exist as the fossil record is utterly incomplete.
Recent research has analyzed mt and nDNA sequences
, morphological
, and biogeographical data to study the phylogenetic relationships of cracid birds, namely the relationships among the genera (Pereira et al., 2002), the relationships between the species of curassows (Pereira & Baker, 2004) and between the piping- and Wattled Guans (Grau et al., 2005). The traditional groups - chachalacas, guans, and curassows - are verified as distinct clade
s, but the Horned Guan
represents the sole survivor of a very distinct and ancient lineage.
In addition, the molecular data suggest that the Cracidae originated in the Late Cretaceous
, but the authors caution that this cannot be more than a hypothesis at present: as the rate of molecular evolution is neither constant over time nor uniform between genera and even species, dating based on molecular information has a very low accuracy over such long timespans and needs to be corroborated by fossil
evidence. The fossil record of cracids is limited to a single doubtfully distinct genus of chachalaca, Boreortalis (Hawthorn Early Miocene
of Florida
, USA; may actually be a junior synonym of Ortalis) and some species in the modern genus Ortalis, however. This does not provide any assistance in evaluating the hypothesis (Pereira et al., 2002) that the split between the 4 main lineages of our time occurred quite rapidly, approximately in the Oligocene
or slightly earlier, somewhere between 40 and 20 mya.
The genera Procrax, Palaeonossax and Paleophasianus are often considered cracids, but this is not certain at all; they may belong to a related extinct lineage. It is unfortunate that of these too, few good fossils are known, as they date to about the time when the modern groups presumably diverged. Should they be cracids, they are not unlikely to represent either some of the last members of the family before guans, chachalacas, etc. evolved, or very early representatives of these lineages.
Thus, the assumption that the modern diversity started to evolve in the late Paleogene
, continuing throughout the Miocene
and onwards, must also be considered hypothetical given the lack of robust evidence. Still, the "molecular" scenario is entirely possible considering what is known about the evolution and radiation of the Galloanserae, and consistent with the paleogeography of the Americas
. The ichnotaxon
Tristraguloolithus cracioides is based on fossil eggshell fragments from the Late Cretaceous Oldman Formation
of southern Alberta, Canada which are similar to chachalaca eggs (Zelenitsky et al., 1996), but in the absence of bone material their relationships cannot be determined except that they are apparently not from a dinosaur
.
By comparison, speciation within curassows (Crax
, Nothocrax, Pauxi
and Mitu
) and the piping/wattled guans is supported by better evidence. It was usually caused by changes in topography
which divided populations (vicariant speciation), mainly due to the uplift of the Andes
which led to the establishment of the modern river basins. The distribution of curassow and piping-guan species for the most part follows the layout of these river systems, and in the latter case, apparently many extinction
s of populations in lowland areas (Grau et al., 2005). Another result was that the Wattled Guan
belongs to the same genus as the piping-guans, which thus use the older name Aburria (Grau et al., 2005).
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 family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Cracidae.
These are species of tropical and subtropical 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...
. One species, the Plain Chachalaca
Plain Chachalaca
The Plain Chachalaca, Ortalis vetula, is a large bird in the Cracidae family. It breeds in tropical and subtropical environments from mezquital thickets in the Rio Grande Valley in southernmost Texas, United States to northernmost Costa Rica....
, just reaches southernmost Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
in the USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Two species, the Trinidad Piping Guan and the Rufous-vented Chachalaca
Rufous-vented Chachalaca
The Rufous-vented Chachalaca, Ortalis ruficauda, is a member of an ancient group of birds of the Cracidae family, which are related to the Australasian mound builders. It inhabits northeast Colombia and northern Venezuela where it is called Guacharaca, and in Tobago where it is known as the Cocrico...
occur on the islands of Trinidad and Tobago
Trinidad and Tobago
Trinidad and Tobago officially the Republic of Trinidad and Tobago is an archipelagic state in the southern Caribbean, lying just off the coast of northeastern Venezuela and south of Grenada in the Lesser Antilles...
respectively.
Biology
Cracids are large birds, similar in general appearance to turkeysTurkey (bird)
A turkey is a large bird in the genus Meleagris. One species, Meleagris gallopavo, commonly known as the Wild Turkey, is native to the forests of North America. The domestic turkey is a descendant of this species...
. The guans and curassows live in trees, but the smaller chachalacas are found in more open scrubby habitats. Many species are fairly long tailed, which may be an aide to navigating their largely arboreal existence. They are generally dull-plumaged, but the curassows and some guans have colourful facial ornaments. The birds are particular vocal, with the chachalacas taking their name from the sound of their call. Cracids range in size from the Little Chachalaca
Little Chachalaca
The Little Chachalaca is a small bird found only in the northern part of South America. It grows to about 38 cm in length and weighs . This bird lives mostly in trees. It is a member of the Cracidae family, and is found in northern Brazil, French Guiana, Suriname, Guyana and Venezuela...
(Ortalis motmot), at as little as 38 cm (15 in) and 350 g (12.5 oz), to the Great Curassow
Great Curassow
The Great Curassow is a large, pheasant-like bird from the Neotropics. At in length and in weight, this is a very large cracid. No other cracid match its maximum weight, but its length is matched by a few other cracids....
(Crax rubra), at nearly 1 m (40 in) and 4.3 kg (9.5 lbs).
These species feed on fruit, insects and worms. They build nests in trees, and lay two to three large white eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
, which only the female incubates alone. The young are precocial
Precocial
In biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial," where the young are born or hatched helpless. Extremely precocial species may be called...
and are born with an instinct to immediately climb and seek refuge in the nesting tree. They are able to fly within days of hatching.
Systematics and evolution
The Cracidae are an ancient group related to the AustralasiaAustralasia
Australasia is a region of Oceania comprising Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean. The term was coined by Charles de Brosses in Histoire des navigations aux terres australes...
n Mound-builders
Mound-builders
The megapodes, also known as incubator birds or mound-builders, are stocky, medium-large chicken-like birds with small heads and large feet in the family Megapodiidae. Their name literally means large foot , and is a reference to the heavy legs and feet typical of these terrestrial birds...
. They are sometimes united with these in a distinct order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
, "Craciformes", but this is not supported by more recent research which suggests that either is a well-marked, basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
lineage of Galliformes
Galliformes
Galliformes are an order of heavy-bodied ground-feeding domestic or game bird, containing turkey, grouse, chicken, New and Old World Quail, ptarmigan, partridge, pheasant, and the Cracidae. Common names are gamefowl or gamebirds, landfowl, gallinaceous birds or galliforms...
.
- Subfamily Penelopinae, Guans
- Genus Penelopina
- Highland GuanHighland GuanThe Highland Guan is a species of bird in the Cracidae family. It is found in the highlands of El Salvador, Guatemala, Honduras, southern Mexico, and Nicaragua.Its natural habitat is subtropical or tropical moist montane forest...
, Penelopina nigra
- Highland Guan
- Genus ChamaepetesChamaepetesChamaepetes is a genus of bird in the Cracidae family. It contains the following species:* Sickle-winged Guan * Black Guan...
- Black GuanBlack GuanThe Black Guan is a species of bird in the Cracidae family.It is found in Costa Rica and Panama.Its natural habitat is subtropical or tropical moist montanes.It is threatened by habitat loss...
, Chamaepetes unicolor - Sickle-winged GuanSickle-winged GuanThe Sickle-winged Guan is a species of bird in the Cracidae family.It is found in Bolivia, Colombia, Ecuador, and Peru. Its natural habitat is subtropical or tropical moist montane forests...
, Chamaepetes goudotii
- Black Guan
- Genus PenelopePenelope (genus)Penelope is a bird genus in the Cracidae family consisting of a number of large turkey-like arboreal species, the typical guans. The range of these species is in forests from southern Mexico to tropical South America. These largish birds have predominately brown plumage and have relatively small...
(15 species) - Genus Aburria -
- Wattled GuanWattled GuanThe Wattled Guan is a species of bird in the Cracidae family. It is a fairly large black cracid with blue-based, black-tipped beak and a long, red-and-yellow wattle. It is 1190-1550 grams and is 72.5-77.5 cm long long.It is found in Colombia, Ecuador, Peru, and Venezuela...
, Aburria aburri
- Wattled Guan
- Genus Pipile (4 species, the Piping Guans)
- Genus Penelopina
Subfamily N.N.
-
- Genus Ortalis - Chachalacas (12 species)
- Subfamily Oreophasinae
- Genus Oreophasis, Horned Guan
- Subfamily Cracinae, Curassows
- Genus Nothocrax
- Nocturnal CurassowNocturnal CurassowThe Nocturnal Curassow is a species of bird in the Cracidae family.It is found in Brazil, Colombia, Ecuador, Peru, and Venezuela....
, Nothocrax urumutum
- Nocturnal Curassow
- Genus CraxCraxCrax is a genus of curassows from tropical South America. Only the Great Curassow ranges north through Central America as far as Mexico.The variety of male bill ornament shapes and colors is typical for this genus, as is a curly crest and a contrasting white or rufous crissum...
(7 species) - Genus MituMitu (bird)Mitu is a genus of curassows, large birds in the family Cracidae. They are found in humid tropical forests in South America. Their plumage is iridescent black with a white or rufous crissum and tail-tip, and their legs and bills are red...
- Crestless CurassowCrestless CurassowThe Crestless Curassow is a species of bird in the Cracidae family.It is found in Brazil, Colombia, Guyana, and Venezuela.Its natural habitat is subtropical or tropical moist lowland forests.-References:...
, Mitu tomentosum - Salvin's CurassowSalvin's CurassowThe Salvin's Curassow is a species of bird in the Cracidae family.It is found in Colombia, Ecuador, and Peru.Its natural habitat is subtropical or tropical moist lowland forests....
, Mitu salvini - Razor-billed CurassowRazor-billed CurassowThe Razor-billed Curassow is a species of bird in the Cracidae family. It is found throughout a large part of the Amazon Rainforest, though largely restricted to regions south of the Amazon River. Unlike other members of the genus Mitu, its crissum is deep chestnut and the tail-tip is white...
, Mitu tuberosum - Alagoas CurassowAlagoas CurassowThe Alagoas Curassow, Mitu mitu, is a large, mainly glossy black pheasant-like bird. It was formerly found in forests in north-eastern Brazil, but it is now extinct in the wild. A captive population exists...
, Mitu mitu (extinct in the wild)
- Crestless Curassow
- Genus PauxiPauxiThe genus Pauxi consist of the two species of helmeted curassows, terrestrial black fowl with ornamental casque on their heads. Both are found in South America.This genus contains only 2 species, namely...
, Helmeted curassows (2 species)
- Genus Nothocrax
Alternatively, all subfamilies except the Penelopinae could be lumped into the Cracinae. As the initial radiation of cracids is not well resolved at present (see below), the system used here seems more appropriate. It is also quite probable that entirely extinct subfamilies exist as the fossil record is utterly incomplete.
Evolution
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...
, morphological
Morphology (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....
, and biogeographical data to study the phylogenetic relationships of cracid birds, namely the relationships among the genera (Pereira et al., 2002), the relationships between the species of curassows (Pereira & Baker, 2004) and between the piping- and Wattled Guans (Grau et al., 2005). The traditional groups - chachalacas, guans, and curassows - are verified as distinct clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
s, but the Horned Guan
Horned Guan
The Horned Guan, Oreophasis derbianus is a large, approximately 85 cm long, turkey-like bird with glossed black upperparts plumage, red legs, white iris, yellow bill and a red horn on top of head. The breast and upper belly are white, and its long tail feathers are black with white band near...
represents the sole survivor of a very distinct and ancient lineage.
In addition, the molecular data suggest that the Cracidae originated in the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
, but the authors caution that this cannot be more than a hypothesis at present: as the rate of molecular evolution is neither constant over time nor uniform between genera and even species, dating based on molecular information has a very low accuracy over such long timespans and needs to be corroborated by fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
evidence. The fossil record of cracids is limited to a single doubtfully distinct genus of chachalaca, Boreortalis (Hawthorn Early Miocene
Early Miocene
The Early Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages....
of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, USA; may actually be a junior synonym of Ortalis) and some species in the modern genus Ortalis, however. This does not provide any assistance in evaluating the hypothesis (Pereira et al., 2002) that the split between the 4 main lineages of our time occurred quite rapidly, approximately in the Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
or slightly earlier, somewhere between 40 and 20 mya.
The genera Procrax, Palaeonossax and Paleophasianus are often considered cracids, but this is not certain at all; they may belong to a related extinct lineage. It is unfortunate that of these too, few good fossils are known, as they date to about the time when the modern groups presumably diverged. Should they be cracids, they are not unlikely to represent either some of the last members of the family before guans, chachalacas, etc. evolved, or very early representatives of these lineages.
Thus, the assumption that the modern diversity started to evolve in the late Paleogene
Paleogene
The Paleogene is a geologic period and system that began 65.5 ± 0.3 and ended 23.03 ± 0.05 million years ago and comprises the first part of the Cenozoic Era...
, continuing throughout the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
and onwards, must also be considered hypothetical given the lack of robust evidence. Still, the "molecular" scenario is entirely possible considering what is known about the evolution and radiation of the Galloanserae, and consistent with the paleogeography of the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...
. The ichnotaxon
Ichnotaxon
An ichnotaxon is defined by the International Code of Zoological Nomenclature as "a taxon based on the fossilized work of an organism", that is, the non-human equivalent of an artifact. Ichnotaxa are names used to identify and distinguish morphologically distinctive ichnofossils, more commonly...
Tristraguloolithus cracioides is based on fossil eggshell fragments from the Late Cretaceous Oldman Formation
Oldman Formation
The Oldman Formation is the middle member of the Judith River Group, a major geologic unit in southern Alberta. The formation is widely recognized as bearing a great number of well preserved dinosaur skeletons, as well as other fossils.-Age:...
of southern Alberta, Canada which are similar to chachalaca eggs (Zelenitsky et al., 1996), but in the absence of bone material their relationships cannot be determined except that they are apparently not from a dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
.
By comparison, speciation within curassows (Crax
Crax
Crax is a genus of curassows from tropical South America. Only the Great Curassow ranges north through Central America as far as Mexico.The variety of male bill ornament shapes and colors is typical for this genus, as is a curly crest and a contrasting white or rufous crissum...
, Nothocrax, Pauxi
Pauxi
The genus Pauxi consist of the two species of helmeted curassows, terrestrial black fowl with ornamental casque on their heads. Both are found in South America.This genus contains only 2 species, namely...
and Mitu
Mitú
Mitú is the capital city of the department of Vaupés in Colombia. The town of Mitu is the most remote Capital of Department in Colombia.In November, 1998 an estimated 1,900 FARC guerrilla members of the Eastern Bloc of the FARC-EP tried to take over the town by force, against 120 National Police...
) and the piping/wattled guans is supported by better evidence. It was usually caused by changes in topography
Topography
Topography is the study of Earth's surface shape and features or those ofplanets, moons, and asteroids...
which divided populations (vicariant speciation), mainly due to the uplift of the Andes
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
which led to the establishment of the modern river basins. The distribution of curassow and piping-guan species for the most part follows the layout of these river systems, and in the latter case, apparently many extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
s of populations in lowland areas (Grau et al., 2005). Another result was that the Wattled Guan
Wattled Guan
The Wattled Guan is a species of bird in the Cracidae family. It is a fairly large black cracid with blue-based, black-tipped beak and a long, red-and-yellow wattle. It is 1190-1550 grams and is 72.5-77.5 cm long long.It is found in Colombia, Ecuador, Peru, and Venezuela...
belongs to the same genus as the piping-guans, which thus use the older name Aburria (Grau et al., 2005).
External links
- Cracid Specialist Group - an origanzation of 200 'cracidologists'
- BirdPhotos.com - high resolution photos of most species
- Cracidae videos on the Internet Bird Collection
- Cracid sounds on xeno-canto.org