Helmeted Curassow
Encyclopedia
The Helmeted Curassow or Northern Helmeted Curassow', (Pauxi pauxi) is a large (up to 91 cm long) terrestrial black curassow
with a small head, large bluish grey casque on forehead, red bill
, white-tipped tail feathers, greenish glossed mantle and breast feathers, and white below. Both sexes are similar. The male, at 3.6 kg (8 lbs), is larger than the female, at 2.6 kg (5.8 lbs). Some rare rufous morph female has a black barred and reddish brown plumage. For some time, it also contained the Horned Curassow taxa as subspecies
. Nowadays its southern congener
is considered a distinct species P. unicornis.
One of the largest birds in its habitat
, the Helmeted Curassow is distributed in the eastern Andes
of Venezuela
and Colombia
. The diet consists mainly of seeds, fruits, insects and small animals. The female lays two cream colored eggs and incubates it for about 30 days.
The Helmeted Curassow is listed on Appendix II of CITES. Formerly classified as an Vulnerable species
by the IUCN, recent research shows that its numbers are decreasing more and more rapidly. It is consequently uplisted to Endangered status in 2008.
:
Their evolution
ary history is not well researched compared to other curassows. The helmeted curassows probably are a lineage of Late Miocene
(Tortonian
-Messinian
, about 8-7 million years ago) origin. This species' present-day distribution suggests that it became isolated some 6 million years ago as its mountain range uplifted. It is not known when gene flow
between the subspecies ceased.
Curassow
Curassows are one of the three major groups of cracid birds. Three of the four genera are restricted to tropical South America; a single species of Crax ranges north to Mexico...
with a small head, large bluish grey casque on forehead, red bill
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...
, white-tipped tail feathers, greenish glossed mantle and breast feathers, and white below. Both sexes are similar. The male, at 3.6 kg (8 lbs), is larger than the female, at 2.6 kg (5.8 lbs). Some rare rufous morph female has a black barred and reddish brown plumage. For some time, it also contained the Horned Curassow taxa as subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
. Nowadays its southern congener
Congener
Congener has several different meanings depending on the field in which it is used. Colloquially, it is used to mean a person or thing like another, in character or action.-Biology:In biology, congeners are organisms within the same genus...
is considered a distinct species P. unicornis.
One of the largest birds in its habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
, the Helmeted Curassow is distributed in the eastern 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...
of Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
and Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
. The diet consists mainly of seeds, fruits, insects and small animals. The female lays two cream colored eggs and incubates it for about 30 days.
The Helmeted Curassow is listed on Appendix II of CITES. Formerly classified as an Vulnerable species
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
by the IUCN, recent research shows that its numbers are decreasing more and more rapidly. It is consequently uplisted to Endangered status in 2008.
Taxonomy
There are two subspeciesSubspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
:
- Mérida Helmeted Curassow, Pauxi pauxi pauxi
- Cordillera de MéridaCordillera de MéridaThe Cordillera de Mérida is a series of mountain ranges, or massif, in northwestern Venezuela. The Cordillera de Mérida is a northeastern extension of the Andes Mountains. The ranges run southwest–northeast between the Venezuelan–Colombian border and the Venezuelan coastal range...
into Cordillera Oriental, ColombiaCordillera Oriental, ColombiaThe Cordillera Oriental is one of three main mountain ranges that divides the Cordillera in the Andes Mountains of Colombia.It extends from southeast to northeast from the "Colombian Massif" in Huila to the Perijá Mountains in La Guajira.... - Casque larger, egg-shaped
- Perijá Helmeted Curassow, Pauxi pauxi gilliardi
- Serrania del PerijaSerrania del PerijaThe Serranía del Perijá, Cordillera de Perijá or Sierra de Perijá is a mountain range, an extension of the eastern Andean branch , in northern South America, between Colombia and Venezuela, ending further north in the Guajira Desert, a total distance of about 310 km...
- Casque smaller, less bulbous, rather cylindrical in shape.
Their evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
ary history is not well researched compared to other curassows. The helmeted curassows probably are a lineage of Late 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...
(Tortonian
Tortonian
The Tortonian is in the geologic timescale an age or stage of the late Miocene that spans the time between 11.608 ± 0.005 Ma and 7.246 ± 0.005 Ma . It follows the Serravallian and is followed by the Messinian....
-Messinian
Messinian
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.332 ± 0.005 Ma...
, about 8-7 million years ago) origin. This species' present-day distribution suggests that it became isolated some 6 million years ago as its mountain range uplifted. It is not known when gene flow
Gene flow
In population genetics, gene flow is the transfer of alleles of genes from one population to another.Migration into or out of a population may be responsible for a marked change in allele frequencies...
between the subspecies ceased.