The chachalacas, guans, and curassows are

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

s in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Cracidae. These are species of tropical and subtropical Central and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. The range of one species, the plain chachalaca, just reaches southernmost parts of

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. Two species, the Trinidad piping guan and the rufous-vented chachalaca occur on the islands of

Trinidad and Tobago Trinidad and Tobago, officially the Republic of Trinidad and Tobago, is the southernmost island country in the Caribbean, comprising the main islands of Trinidad and Tobago, along with several List of islands of Trinidad and Tobago, smaller i ...

respectively.

Systematics and evolution

The family Cracidae was introduced (as Craxia) by the French

polymath A polymath or polyhistor is an individual whose knowledge spans many different subjects, known to draw on complex bodies of knowledge to solve specific problems. Polymaths often prefer a specific context in which to explain their knowledge, ...

Constantine Samuel Rafinesque Constantine Samuel Rafinesque-Schmaltz (; 22 October 178318 September 1840) was a French early 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ult ...

in 1815. The Cracidae are an ancient group that were thought to be related to the

Australasia Australasia is a subregion of Oceania, comprising Australia, New Zealand (overlapping with Polynesia), and sometimes including New Guinea and surrounding islands (overlapping with Melanesia). The term is used in a number of different context ...

n mound-builders of family Megapodiidae. The two families they were sometimes united in a distinct order, Craciformes, as in Munroe and Sibley's 1993 ''World Checklist of Birds''. However, the group is not monophyletic and more recent phylogenetic studies have found Megapodiidae and Cracidae to be successive early branching lineages of

Galliformes Galliformes is an order (biology), order of heavy-bodied ground-feeding birds that includes turkey (bird), turkeys, chickens, Old World quail, quail, and other landfowl. Gallinaceous birds, as they are called, are important in their ecosystems ...

Internal Phylogeny

Cladogram based on the study by De Chen and collaborators published in 2021. The numbers of species are from the list maintained by Frank Gill, Pamela Rasmussen and David Donsker on behalf of the

International Ornithologists' Union The International Ornithologists' Union (IOU) is an international organization for the promotion of ornithology Ornithology, from Ancient Greek ὄρνις (''órnis''), meaning "bird", and -logy from λόγος (''lógos''), meaning "study", ...

Classification

Extinct species assignment follows the Mikko's Phylogeny Archive and Paleofile.com websites. * Genus †'' Procrax'' Tordoff & Macdonald 1957 ** †'' Procrax brevipes'' Tordoff & Macdonald 1957 * Genus †'' Paleophasianus'' Wetmore 1940 ** †'' Paleophasianus meleagroides'' Wetmore 1940 * Genus †'' Taoperdix'' Milne-Edwards 1869 ** †'' Taoperdix pesseiti'' (Gervais 1862) Milne-Edwards 1869 *

Subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Penelopinae (Guans) ** Genus '' Aburria'' Reichenbach 1853 *** Subgenus (''Aburria'') **** Wattled guan, ''Aburria aburri'' (Lesson 1828) Reichenbach 1853 *** Subgenus ('' Pipile'') Bonaparte 1856 (piping guans) **** Black-fronted piping guan, ''Pipile jacutinga'' (von Spix 1825) **** Red-throated piping guan, ''Pipile cujubi'' (Pelzeln 1858) **** Trinidad piping guan, ''Pipile pipile'' (Jacquin 1784) **** Blue-throated piping guan, ''Pipile cumanensis'' (Jacquin 1784) **** White-throated piping guan, ''Pipile grayi'' (Pelzeln 1858) ** Genus '' Chamaepetes'' Wagler 1832 *** Black guan, ''Chamaepetes unicolor'' Salvin 1867 *** Sickle-winged guan, ''Chamaepetes goudotii'' (Lesson 1828) ** Genus '' Penelope'' Merrem 1786 (15 species) *** Band-tailed guan, ''Penelope argyrotis'' (Bonaparte 1856) *** Bearded guan, ''Penelope barbata'' Chapman 1921 *** Baudo guan, ''Penelope ortoni'' Salvin 1874 *** Andean guan, ''Penelope montagnii'' (Bonaparte 1856) *** Marail guan, ''Penelope marail'' (Müller 1776) *** Rusty-margined guan, ''Penelope superciliaris'' Temminck 1815 *** Red-faced/Dabbene's guan''Penelope dabbenei'' Hellmayr & Conover 1942 *** Crested guan, ''Penelope purpurascens'' Wagler 1830 *** Cauca guan, ''Penelope perspicax'' Bangs 1911 *** White-winged guan, ''Penelope albipennis'' Taczanowski 1878 ***

Spix's guan Spix's guan (''Penelope jacquacu'') is a species of bird in the family Cracidae. It is "the prototypical cracid of the Amazonian lowlands."del Hoyo, J. and G. M. Kirwan (2020). Spix's Guan (''Penelope jacquacu''), version 1.0. In Birds of the Wo ...

, ''Penelope jacquacu'' von Spix 1825 *** Dusky-legged guan, ''Penelope obscura'' Temminck 1815 *** White-crested guan, ''Penelope pileata'' Wagler 1830 *** Chestnut-bellied guan, ''Penelope ochrogaster'' Pelzeln 1870 *** White-browed guan, ''Penelope jacucaca'' von Spix 1825 ** Genus ''

Penelopina The highland guan (''Penelopina nigra'') is a species of bird in the family Cracidae. It is found in the highlands of El Salvador, Guatemala, Honduras, southern Mexico, and Nicaragua. Its natural habitat is subtropical or tropical moist montane ...

'' Reichenbach 1861 *** Highland guan, ''Penelopina nigra'' (Fraser 1852) Reichenbach 1861 * Subfamily Cracinae ** Tribe Ortalidini Donegan 2012 *** Genus '' Ortalis'' Merrem 1786 (chachalacas, 16 species) **** †'' Ortalis affinis'' Feduccia & Wilson 1967 **** †'' Ortalis phengites'' Wetmore 1923 **** †'' Ortalis pollicaris'' Miller 1944 **** †'' Ortalis tantala'' Wetmore 1933 **** Plain chachalaca, ''Ortalis vetula'' (Wagler 1830) **** Grey-headed chachalaca, ''Ortalis cinereiceps'' Gray 1867 **** Chestnut-winged chachalaca, ''Ortalis garrula'' (von Humboldt 1805) **** Rufous-vented chachalaca, ''Ortalis ruficauda'' Jardine 1847 **** Rufous-headed chachalaca, ''Ortalis erythroptera'' Sclater & Salvin 1870 **** Rufous-bellied chachalaca, ''Ortalis wagleri'' Gray 1867 **** West Mexican chachalaca ''Ortalis poliocephala'' (Wagler 1830) **** Chaco chachalaca, ''Ortalis canicollis'' (Wagler 1830) **** White-bellied chachalaca, ''Ortalis leucogastra'' (Gould 1843) **** Speckled chachalaca, ''Ortalis guttata'' (von Spix 1825) **** Colombian chachalaca, ''Ortalis columbiana'' Hellmayr 1906 **** East Brazilian chachalaca ''Ortalis araucuan'' (von Spix 1825) **** Scaled chachalaca, ''Ortalis squamata'' Lesson 1829 **** Little/variable/Guiana chachalaca, ''Ortalis motmot'' (Linnaeus 1766) **** Chestnut-headed chachalaca, ''Ortalis ruficeps'' (Wagler 1830) **** Buff-browed chachalaca, ''Ortalis superciliaris'' Gray 1867 ** Tribe Oreophasini Bonaparte 1853 *** Genus '' Oreophasis'' Gray 1844 **** Horned guan, ''Oreophasis derbianus'' Gray 1844 ** Tribe Cracini Rafinesque 1815 (curassows) *** Genus '' Crax'' Linnaeus 1758 (7 species) **** Great curassow, ''Crax rubra'' Linnaeus 1758 **** Prince Albert's/Blue-billed/knobbed curassow, ''Crax alberti'' Fraser 1852 **** Yellow-knobbed curassow, ''Crax daubentoni'' Gray 1867 **** Globulose/Wattled/Yarrell's curassow, ''Crax globulosa'' von Spix 1825 **** Red-billed curassow, ''Crax blumenbachii'' von Spix 1825 **** Black curassow, ''Crax alector'' Linnaeus 1766 **** Bare-faced curassow, ''Crax fasciolata'' von Spix 1825 *** Genus '' Mitu'' Lesson 1831 (razor-billed curassows) **** Crestless curassow, ''Mitu tomentosum'' (von Spix 1825) **** Salvin's curassow, ''Mitu salvini'' Reinhardt 1879 **** Razor-billed curassow, ''Mitu tuberosum'' (von Spix 1825) **** Alagoas curassow, ''Mitu mitu'' (Linnaeus 1766) (extinct in the wild) *** Genus '' Nothocrax'' Burmeister 1856 **** Nocturnal curassow, ''Nothocrax urumutum'' (von Spix 1825) Burmeister 1856 *** Genus '' Pauxi'' Temminck 1813 (helmeted curassows) **** Horned curassow, ''Pauxi unicornis'' Bond & Meyer de Schauensee 1939 **** Sira curassow, ''Pauxi koepckeae'' Weske & Terborgh 1971 **** Helmeted curassow, ''Pauxi pauxi'' (Linnaeus 1766) Temminck 1813 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 Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

subfamilies exist as the

fossil record A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

is utterly incomplete.

Evolution

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 In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

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 The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

, 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 A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

evidence. The fossil record of cracids is limited to a single doubtfully distinct genus of chachalaca, '' Boreortalis'' (Hawthorn

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

, 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 The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

or slightly earlier, somewhere between 40 and 20 mya. The genera '' Procrax'' and '' Palaeonossax'' are often considered cracids, but this is not certain at all; they may belong to a related extinct lineage. 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 The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...

, continuing throughout the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

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 Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...

. The

ichnotaxon An ichnotaxon (plural ichnotaxa) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact. ''Ichnotaxon'' comes from the Ancient Greek (''íchnos'') meaning "track" and English , itself derived from ...

''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 Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

. 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 Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the landforms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary sci ...

which divided populations ( vicariant speciation), mainly due to the uplift of the

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

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 is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

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). Originally interpreted as a

turkey Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...

by Othniel Charles Marsh, '' Meleagris antiquus'' was referred to as Cracidae in 1964 by Pierce Brodkorb. It is nowadays considered unambiguously to be a Cariamiformes under Bathornithidae, and indeed a very different animal from cracids, being a 2 meter tall terrestrial predator. Similarly, '' Palaeophasianus'' has been reassigned to Geranoididae, a lineage of large, ostrich-like stem- cranes.

Description

Cracids are large birds, similar in general appearance to turkeys. 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 in this family are particularly 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 and , to the great curassow (''Crax rubra''), at nearly and .

Behaviour and ecology

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 Precocial species in birds and mammals are those in which the young are relatively mature and mobile from the moment of birth or hatching. They are normally nidifugous, meaning that they leave the nest shortly after birth or hatching. Altricial ...

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.

Footnotes

References

* * del Hoyo, J. (1994). Family Cracidae (Chachalacas, Guans and Curassows). Pp. 310–363 in; del Hoyo, J., Elliott, A. & Sargatal, J. eds. ''Handbook of the Birds of the World'', Vol. 2. New World Vultures to Guineafowl. Lynx Edicions, Barcelona. * * *

External links

Cracid Specialist Group – an organization of 200 'cracidologists'BirdPhotos.com – high resolution photos of most speciesCracidae videos
on the Internet Bird Collection {{Authority control Bird families Birds of the Americas Taxa named by Constantine Samuel Rafinesque