Pavo Real/Peacock/Pavo cristatus

Foto: Alex Pareja

Nombre en español: Pavo Real

Nombre en ingles: Peacock

Nombre científico: Pavo cristatus

Familia: Phasianidae

Canto: Oscar Campbell

El pavo real común​ (Pavo cristatus), también conocido como pavón real, pavo real de la India y pavo real de pecho azul, es una especie de ave galliforme de la familia Phasianidae,​ una de las dos especies del género Pavo, que desde tiempos antiguos destacó entre los animales admirados por el hombre a causa del extraordinario abanico policromado que constituye la cola de los machos.

Distribución y hábitat

El pavo real es originario del sur de Asia, encontrándose por todo el subcontinente indio y en zonas secas de Sri Lanka, principalmente en altitudes inferiores a los 1800 m, habitando en regiones cercanas a los 2000 m en raras ocasiones.4​ Viven en bosques caducifolios tanto húmedos como secos, pero se adaptan a la vida en regiones de cultivos y alrededor de poblaciones humanas, frecuentemente donde hay disponibilidad de agua.

Foto: Gilberto Collazos

Algunos autores sugieren que esta especie fue introducida en Europa por Alejandro Magno,​ mientras que otros creen que se encontraba ya en la Antigua Grecia por el año 450 a. C., pudiendo ser introducida incluso antes.6​ Desde entonces, ha sido introducido en muchas otras partes del mundo, llegando a ser salvaje en algunas zonas.

Descripción

El pavo real es una especie con un fuerte dimorfismo sexual. El macho de esta especie tiene una longitud de entre 100-115 cm del pico a la cola, alcanzando los 195-225 cm hasta el extremo de las largas plumas especializadas que conforman el abanico —cola secundaria— cuando están plenamente desarrolladas. Su peso es de 4-6 kg. La hembra es más pequeña, con una longitud de unos 95 cm y un peso de 2,75-4 kg.

Macho

El plumaje de la parte anterior del animal es azul cobalto iridiscente, con reflejos verdes a ambos lados de la cabeza. En esta se inserta un pico de color gris y está coronada por un copete de plumas con el eje desnudo blanco y las puntas azul verdosas. Sobre el ojo y debajo de este existen dos líneas blancas de piel sin plumas.

Foto: Alex Pareja

La región de la espalda está formada por plumas de aspecto escamado de colores verdes y negros con reflejos bronces y cobres. Las alas y su inserción escapular son negras barradas con blanco, pero con las plumas primarias, visibles únicamente durante el vuelo, de color canela. La verdadera cola es marrón oscura, mientras que las supracobertoras que forman la cola secundaria son de color verde-dorado con tonos iridiscentes de bronce y azul, tachonadas de ocelos con franjas azules, marrones y verdes. Algunas de estas plumas especializadas carecen de ocelos y terminan en su extremo en una semiluna negra.

Hembra y crías

La hembra tiene la cabeza de color marrón rojizo con la cara blanca y un copete similar al del macho, siendo las puntas de color castaño con bordes verdes. El cuello es verde metálico y las plumas del pecho son de color marrón oscuro con reflejos verdes. La parte superior del cuerpo es de color marrón pardo con manchas pálidas. La cola y las primarias y secundarias de las alas son marrones oscuras. No poseen las plumas que forman el vistoso abanico del macho. La región inferior es blanquecina.

Las crías son de color pardo-amarillento con un moteado más oscuro durante las etapas más tempranas. La nuca presenta una mancha marrón oscura que se conecta con los ojos. El plumaje de los machos jóvenes es parecido al de las hembras, pero con las alas castañas y un copete poco desarrollado. Estos carecen de la cola secundaria, comenzando a desarrollar las supracoberteras que la conforman durante el segundo año de vida.

Ilustración de un pavo real macho junto a una hembra.

Mutaciones

Existen diferentes variaciones del fenotipo del plumaje del Pavo cristatus debido a distintas mutaciones genéticas. Estas ocurren en muy raras ocasiones en la naturaleza, pero la crianza selectiva en cautiverio ha fijado las diferentes variedades, haciendo comunes algunas de ellas y dejando el término «pavo real azul» para la estirpe salvaje. Estas mutaciones dan lugar a dos tipos de variaciones de color y de patrón. Las variaciones del color producen diferentes tonalidades en todo el plumaje, mientras que las del patrón afectan a regiones o a la distribución del pigmento, necesitando tener de base el color de la estirpe salvaje o una de las variedades. Un color se puede combinar con uno o varios patrones, produciendo distintos pavos reales, como, por ejemplo, un pavo real opal arlequín plateado.

Variedades de color

Pavo real blanco.

  • Blanco: una de las más llamativas variedades. Conseguida gracias al cruce selectivo de pavos que presentaban manchas blancas en su patrón. La mutación que poseen les produce leucismo total, lo que impide que la melanina se deposite en las células plumíferas, dejando el plumaje de machos y hembras completamente blanco. Las crías al nacer son de color amarillo claro.
  • Bronce: el plumaje en la cabeza, el cuello y los ocelos de las supracoberteras son de color marrón intenso, con reflejos verdes metálicos que se acentúan alrededor de la cabeza, oscureciéndose su color en las regiones proximales al cuerpo.
  • Cameo: antes de la temporada de cortejo, el plumaje es marrón oscuro, pero este se va decolorando conforme los días son más largos, pasando a ser de color «café con leche», siendo las alas algo más claras que las supracoberteras. La cabeza y el cuello permanecen de marrón oscuro, mientras los ocelos ofrecen diferentes tonalidades de marrón. El plumaje de la hembra es de color crema. Esta variedad no posee iridiscencias.
  • Charcoal: las regiones que en la estirpe salvaje son azules iridiscentes, son negras mate, sin iridiscencias, en esta variedad. Las supracoberteras son negras grisáceas, con ocelos de tonos oscuros. Las hembras son más oscuras que las pavas azules y sin las iridiscencias verdes del cuello.
  • Jade: la parte anterior del ave es del verde intenso del jade. Las supracoberteras marrones poseen destellos oliváceos con ocelos verdosos.
  • Midnight: similar al color de la estirpe salvaje pero con un melanismo total que le oscurece todo el cuerpo.
  • Opal: la parte anterior del macho es gris oscura, siendo el resto del cuerpo de un gris más claro. La iridiscencia del pecho es violeta y las supracoberteras tienen una tonalidad olivácea con reflejos verdes, azules y púrpuras. Las hembras y sus pollitos son completamente grises.
  • Peach: con la cabeza y sus proximidades, incluido el copete, de un marrón sólido, el resto del cuerpo se va aclarando hacia un tono marrón-anaranjado similar al de los melocotones, llegando a casi blanco. El marrón de las hembras es más claro.
  • Púrpura: el azul del cuello es más intenso, ofreciendo reflejos morados. La banda más próxima al centro oscuro del ocelo es de color púrpura. El cuello de las hembras también poseen reflejos morados.​
  • Taupe: parecido a la variedad opal, pero el color del macho es gris claro uniforme, con diferentes tonalidades de marrones claros.

Variedades del patrón

  • Ala negra: inicialmente fue considerada una subespecie del fenotipo salvaje (P. c. nigripennis), pero realmente es una variación genética que produce melanismo en los machos. La diferencia se da en las plumas terciarias y secundarias de las alas que, en lugar del patrón a rayas, ofrece una coloración completamente negra o con pequeñas motas blancas. El melanismo también afecta al azul del pecho y cuello, siendo más oscuros en el ala negra. El plumaje de la hembra también se ve afectado, siendo todo su cuerpo de color crema con tiras oscuras repartidas de manera aleatoria.
  • Arlequín: posee un leucismo parcial en extensas regiones de su cuerpo, por lo que se observan grandes manchas blancas repartidas de manera aleatoria por el plumaje de ambos sexos, mientras que las existen otras zonas pigmentadas con el color de base.
  • White eye: el ocelo policromado es de color blanco en diferentes proporciones. Las plumas primarias de las alas también son blancas. El resto del plumaje puede ser de cualquier variedad de color.
  • Arlequín plateado: se denomina así a la suma de las dos variaciones de patrones anteriores, produciendo un pavo real arlequín con ocelos blancos. La mayoría de su plumaje es de color blanco con pequeñas regiones de color plateado y azul. Actualmente se intenta combinar con las distintas variaciones de color.
Foto: Enrique Ascanio

Híbridos

Se conoce como «pavo real Spalding» a las crías híbridas viables resultantes del cruce entre un ejemplar de Pavo cristatus de cualquier variedad y uno de la especie afín Pavo muticus —pavo real cuelliverde—. Se denomina así en honor a Keith Spalding de California, la primera criadora de estas aves. El plumaje de este híbrido es una combinación de las dos especies, siendo verde con algunos reflejos dorados en el cuello y pecho. El copete es medianamente compacto y alargado. En la cara se observa una zona blanca desnuda formada por la piel orbital que se extiende alrededor de los ojos y los oídos. Tiene una mayor longitud y envergadura que el pavo real común, pero siendo el cuerpo algo más esbelto.

Comportamiento

La alimentación es fundamentalmente omnívora, compuesta principalmente por semillas, frutos, bayas, plantas, verduras, insectos, ranas y pequeños reptiles.»Los pavos reales son sinuosos como culebras, huidizos como los gatos y cautelosos como los búfalos viejos cuando vigilan los movimientos de sus enemigos»Edward Charles Stuart Baker

Foto: Ramiro Ramirez

Detalle de las plumas coberteras del penacho, mostrando los ocelos policromados.

El pavo real se alimenta y nidifica en tierra, en un hueco de poca profundidad que suele tapar con ramas u hojas. A pesar de su tamaño y largas plumas puede efectuar vuelos cortos, que realiza especialmente para posarse en las ramas de los árboles donde descansa y pasa la noche.

Son aves territoriales y polígamas; cada macho debe tener cuatro o cinco hembras que no pueden estar muy juntas.

La época de celo y reproducción es en primavera, donde el macho se aparea hasta con seis hembras. La puesta es de cuatro a ocho huevos de color castaño claro, que son incubados exclusivamente por la hembra durante veintiocho días, al término de los cuales nacen los polluelos dotados de unas pocas plumas parduzcas a modo de pequeño penacho.

Sonidos

Los sonidos que produce el animal no son tan atractivos como su imagen: por lo general consisten en graznidos que pueden relacionarse con el maullido de un gato, y trompeteos asombrosamente graves. En ocasiones emite chillidos que parecen los de un niño pidiendo socorro.

Enfermedades

Son muy sensibles a la humedad excesiva y a las bajas temperaturas, pueden contraer enfermedades respiratorias, tuberculosis e infecciones intestinales.

En temperaturas bajas, dos grados centígrados, pueden llegar a entumecerse de las patas, provocando que pierdan movilidad.

Historia

Esta ave es originaria de la India. Cuando Alejandro Magno conquistó el occidente de la India antigua conoció estas aves y llevó varios ejemplares hasta la ciudad de Babilonia. Desde aquí estas aves se propagaron hasta Persia, Media y luego de estos reinos fue de donde los romanos las llevaron a Italia.

Los antiguos tenían mucho aprecio a la carne y huevos de estas aves. El orador Quinto Hortensio Hórtalo fue el primero que introdujo entre los romanos el gusto por la carne de estas aves que hizo servir en un gran convite que dio cuando fue creado augur. Marco Anfidio Luco fue el primero que discurrió hacerlas andar a manadas para engordarlas.

El pavo real es muy común en los monumentos antiguos. Se ve a Juno acompañada del pavo por estarle particularmente consagrado. Se observa también en las medallas de Samos, célebre por el culto que tributaban a esta diosa y en las medallas romanas en las cuales se ve a Juno regina. En algunas se ve al pavo e los pies de Isis y de la Providencia e indica particularmente la consagración de las emperatrices. Un pavo con la cola desplegada puede considerarse como el símbolo de la vanidad.

En tiempo de la caballería era también muy apreciado el pavo real que se calificaba de noble ave. Su carne era el alimento de los valientes y de los amantes y el ornato de los banquetes. Una figura de pavo servía de blanco a los caballeros que se adiestraban en el ejercicio de las armas y cuando había de pronunciarse algún juramento o solemne voto, se llevaba a la mesa con grande aparato por las damas o damiselas un pavo asado en una gran fuente de oro o plata. Después de haber pronunciado sobre él un voto cada uno de los comensales se distribuía entre todos los asistentes.

Simbolismo, mitología y cultura popular

La simbología del pavo real es larga, ya que su majestuosidad llamó la atención del hombre ya en épocas pasadas. Aunque se le asocie con el concepto de vanidad, el pavo real es, en casi todas las culturas, un símbolo solar relacionado con la belleza, la gloria, la inmortalidad y la sabiduría. Es originario de la India y fue Alejandro Magno quien lo llevó a Occidente junto a su significado simbólico a través de Babilonia, Persia y Asia Menor, alcanzando Grecia en el Período Clásico. Su simbolismo solar está, sin duda, relacionado con su larga cola de colores y sus dibujos en forma de ojos que, debido a su forma circular y a su brillo, conectan también con el ciclo vital y eterno de la naturaleza.

El pavo real es el ave nacional de India. En el hinduismo, el pavo real sirve de montura a Skanda, el dios de la guerra. Numerosas tradiciones, especialmente en el sur de la India y Sri Lanka lo relacionan también con deidades locales, representando por ejemplo al poder del trueno. Muchas de las danzas folclóricas de la India muestran pasos inspirados en el baile de cortejo del pavo real. Una creencia popular de países hindús sostiene que cuando el pavo real despliega su cola es señal de lluvia. En la antigua Grecia, fue el ave simbólica de Hera, la diosa griega más importante del Olimpo, esposa legítima de Zeus y diosa de las mujeres y el matrimonio. Según cuentan, Hera encargó a Argos, un gigante con mil ojos, que vigilase a una de las amantes de su infiel esposo pero fue asesinado por Hermes. Cuando la diosa se enteró de la muerte de Argos, tomó sus cien ojos y los puso en la cola del pavo real, dándole el aspecto que tiene actualmente.

En Roma, las princesas y emperatrices tomaron el pavo real como su símbolo personal. De este modo, el pavo real pasó al simbolismo cristiano fuertemente relacionado con la Gran Diosa por lo que no es difícil comprender su conexión positiva con la Virgen María y las delicias del Paraíso. En la religión cristiana, es considerado símbolo de resurrección de Cristo porque en primavera, tiempo de Pascua, el ave cambia totalmente de plumaje. No se le suele representar con su cola desplegada ya que es una imagen que sugiere vanidad, un concepto contrario a la caridad y la humildad del mensaje del cristianismo. Se pueden ver mosaicos del siglo IV con esta figura en la iglesia de Santa Constancia, en Roma, así como en algunas catacumbas cristianas. En general, las representaciones de pavos reales muestran al ave bebiendo de un cáliz o de una fuente (Fuente de la Vida) simbolizando un renacimiento espiritual, asociado con el bautismo y con la eternidad del alma.

  • La majestuosidad del pavo real llamó la atención del hombre desde épocas antiguas, incorporándolo a la cultura popular y a la religión de diferentes períodos históricos, partiendo de las regiones geográficas que constituyen su hábitat original.
  • En el hinduismo, el pavo real sirve de montura a Kārttikeya o Skanda, el dios de la guerra. Numerosas tradiciones, especialmente en el sur de la India y Sri Lanka lo relacionan así mismo con deidades locales, representando por ejemplo al poder del trueno. Muchas de las danzas folclóricas de la India incluyendo el Bharatha Natyam muestran pasos inspirados en el baile de cortejo del pavo real.
  • Una creencia popular de estos países sostiene que cuando el pavo real despliega su imponente penacho es señal inminente de lluvia.​
  • En la antigua Grecia fue el ave simbólica de Hera.
  • Cuando en el Antiguo Testamento se describen las riquezas del rey Salomón, se incluye al pavo real en posición preponderante:

«Porque el rey Salomón tenía en el mar una flota de naves de Tarsis, con la flota de Hiram. Una vez cada tres años venía la flota de Tarsis, y traía oro, plata, marfil, monos y pavos reales»Primer libro de Reyes, 10:22, Reina-Valera, 1960

  • En el Islam se asocia a Iblís, jefe supremo de los demonios, con el pavo real.
  • En la religión yazidi el pavo real se asocia a su dios Melek Taus.
  • El pavo real es el ave nacional de India.
  • Era un manjar muy apreciado en los festines de la antigua Roma donde el pavo real era un plato casi obligatorio.
  • En la época contemporánea, los principales zoológicos de todo el mundo tienen una colección de pavos reales como uno de los principales atractivos para el público visitante.

Indian peafowl

The Indian peafowl (Pavo cristatus), also known as the common peafowl, and blue peafowl, is a peafowl species native to the Indian subcontinent. It has been introduced to many other countries.

The male peacock is brightly coloured, with a predominantly blue fan-like crest of spatula-tipped wire-like feathers and is best known for the long train made up of elongated upper-tail covert feathers which bear colourful eyespots. These stiff feathers are raised into a fan and quivered in a display during courtship. Despite the length and size of these covert feathers, peacocks are still capable of flight. Peahens lack the train, and have a greenish lower neck and duller brown plumage. The Indian peafowl lives mainly on the ground in open forest or on land under cultivation where they forage for berries, grains but also prey on snakes, lizards, and small rodents. Their loud calls make them easy to detect, and in forest areas often indicate the presence of a predator such as a tiger. They forage on the ground in small groups and usually try to escape on foot through undergrowth and avoid flying, though they fly into tall trees to roost.

The function of the peacock’s elaborate train has been debated for over a century. In the 19th century, Charles Darwin found it a puzzle, hard to explain through ordinary natural selection. His later explanation, sexual selection, is widely but not universally accepted. In the 20th century, Amotz Zahavi argued that the train was a handicap, and that males were honestly signalling their fitness in proportion to the splendour of their trains. Despite extensive study, opinions remain divided on the mechanisms involved.

The bird is celebrated in Hindu and Greek mythology and is the national bird of India. The Indian peafowl is listed as of Least Concern by the International Union for Conservation of Nature (IUCN).

Taxonomy and naming

Carl Linnaeus in his work Systema Naturae in 1758 assigned to the Indian peafowl the technical name of Pavo cristatus (means «crested peafowl» in classical Latin).

The earliest usage of the word in written English is from around 1300 and spelling variants include pecok, pekok, pecokk, peacocke, peocock, pyckock, poucock, pocok, pokok, pokokke, and poocok among others. The current spelling was established in the late 17th century. Chaucer (1343–1400) used the word to refer to a proud and ostentatious person in his simile «proud a pekok» in Troilus and Criseyde (Book I, line 210).

The Greek word for peacock was taos and was related to the Persian «tavus» (as in Takht-i-Tâvus for the famed Peacock Throne). The Ancient Hebrew word tuki (plural tukkiyim) has been said to have been derived from the Tamil tokei but sometimes traced to the Egyptian tekh. In modern Hebrew the word for peacock is «tavas».

Description

Peacocks are a larger sized bird with a length from bill to tail of 100 to 115 cm (39 to 45 in) and to the end of a fully grown train as much as 195 to 225 cm (77 to 89 in) and weigh 4–6 kg (8.8–13.2 lb). The females, or peahens, are smaller at around 95 cm (37 in) in length and weigh 2.75–4 kg (6.1–8.8 lb). Indian peafowl are among the largest and heaviest representatives of the Phasianidae. So far as is known, only the wild turkey grows notably heavier. The green peafowl is slightly lighter in body mass despite the male having a longer train on average than the male of the Indian species. Their size, colour and shape of crest make them unmistakable within their native distribution range. The male is metallic blue on the crown, the feathers of the head being short and curled. The fan-shaped crest on the head is made of feathers with bare black shafts and tipped with bluish-green webbing. A white stripe above the eye and a crescent shaped white patch below the eye are formed by bare white skin. The sides of the head have iridescent greenish blue feathers. The back has scaly bronze-green feathers with black and copper markings. The scapular and the wings are buff and barred in black, the primaries are chestnut and the secondaries are black. The tail is dark brown and the «train» is made up of elongated upper tail coverts (more than 200 feathers, the actual tail has only 20 feathers) and nearly all of these feathers end with an elaborate eye-spot. A few of the outer feathers lack the spot and end in a crescent shaped black tip. The underside is dark glossy green shading into blackish under the tail. The thighs are buff coloured. The male has a spur on the leg above the hind toe.

The adult peahen has a rufous-brown head with a crest as in the male but the tips are chestnut edged with green. The upper body is brownish with pale mottling. The primaries, secondaries and tail are dark brown. The lower neck is metallic green and the breast feathers are dark brown glossed with green. The remaining underparts are whitish. Downy young are pale buff with a dark brown mark on the nape that connects with the eyes. Young males look like the females but the wings are chestnut coloured.

The most common calls are a loud pia-ow or may-awe. The frequency of calling increases before the Monsoon season and may be delivered in alarm or when disturbed by loud noises. In forests, their calls often indicate the presence of a predators such as the tiger. They also make many other calls such as a rapid series of ka-aan..ka-aan or a rapid kok-kok. They often emit an explosive low-pitched honk! when agitated.

Mutations and hybrids

A white peafowl that is maintained by selective breeding in many parks such as this one at the Jardin des Plantes, Paris. This leucistic mutation is commonly mistaken for an albino.

There are several colour mutations of Indian peafowl. These very rarely occur in the wild, but selective breeding has made them common in captivity. The black-shouldered or Japanned mutation was initially considered as a subspecies P. c. nigripennis (or even a species), and was a topic of some interest during Darwin’s time. It is however only a case of genetic variation within the population. In this mutation, the adult male is melanistic with black wings. Young birds with the nigripennis mutation are creamy white with fulvous tipped wings. The gene produces melanism in the male and in the peahen it produces a dilution of colour with creamy white and brown markings. Other variations include the pied and white forms all of which are the result of allelic variation at specific loci.

Cross between a male green peafowl, Pavo muticus and a female Indian peafowl, P. cristatus, produces a stable hybrid called a «spalding», named after Mrs. Keith Spalding, a bird fancier in California. There can be problems if birds of unknown pedigree are released into the wild, as the viability of such hybrids and their offspring is often reduced (see Haldane’s Rule and outbreeding depression).

Distribution and habitat

The Indian peafowl is a resident breeder across the Indian subcontinent and is found in the drier lowland areas of Sri Lanka. In the Indian subcontinent, it is found mainly below an altitude of 1,800 metres (1.1 mi) and in rare cases seen at about 2,000 metres (1.2 mi). It is found in moist and dry-deciduous forests, but can adapt to live in cultivated regions and around human habitations and is usually found where water is available. In many parts of northern India, they are protected by religious practices and will forage around villages and towns for scraps. Some have suggested that the peacock was introduced into Europe by Alexander the Great,[19] while others say the bird had reached Athens by 450 BCE and may have been introduced even earlier. It has since been introduced in many other parts of the world and has become feral in some areas.

Besides its native habitat, the bird has been introduced by humans to the United States, Mexico, Honduras, Colombia, Guyana, Suriname, Brazil, Uruguay, Argentina, South Africa, Portugal, Madagascar, Mauritius, Réunion, Indonesia, Papua New Guinea, Australia, Croatia (Split, island of Lokrum), and elsewhere. In isolated cases, the Indian peafowl has been known to be able to adapt to harsher climates, such as those of northern Canada. The species has been spotted by hunters as far north as Huntsville, Ontario, thriving in its newly adapted northern climate.

Genome sequencing

The first whole-genome sequencing of Indian peafowl identified a total of 15,970 protein-coding sequences, along with 213 tRNAs, 236 snoRNAs, and 540 miRNAs. The peacock genome was found to have less repetitive DNA (8.62%) than that of the chicken genome (9.45%). PSMC analysis suggested that the peacock suffered at least two bottlenecks (around four million years ago and again 450,000 years ago), which resulted in a severe reduction in its effective population size.

Behaviour and ecology

Peafowl are best known for the male’s extravagant display feathers which, despite actually growing from their back, are thought of as a tail. The «train» is in reality made up of the enormously elongated upper tail coverts. The tail itself is brown and short as in the peahen. The colours result not from any green or blue pigments but from the micro-structure of the feathers and the resulting optical phenomena. The long train feathers (and tarsal spurs) of the male develop only after the second year of life. Fully developed trains are found in birds older than four years. In northern India, these begin to develop each February and are moulted at the end of August. The moult of the flight feathers may be spread out across the year.

Peafowl forage on the ground in small groups, known as musters, that usually have a cock and 3 to 5 hens. After the breeding season, the flocks tend to be made up only of females and young. They are found in the open early in the mornings and tend to stay in cover during the heat of the day. They are fond of dust-bathing and at dusk, groups walk in single file to a favourite waterhole to drink. When disturbed, they usually escape by running and rarely take to flight.

Peafowl produce loud calls especially in the breeding season. They may call at night when alarmed and neighbouring birds may call in a relay like series. Nearly seven different call variants have been identified in the peacocks apart from six alarm calls that are commonly produced by both sexes.

Peafowl roost in groups during the night on tall trees but may sometimes make use of rocks, buildings or pylons. In the Gir forest, they chose tall trees in steep river banks. Birds arrive at dusk and call frequently before taking their position on the roost trees. Due to this habit of congregating at the roost, many population studies are made at these sites. The population structure is not well understood. In a study in northern India (Jodhpur), the number of males was 170–210 for 100 females but a study involving evening counts at the roost site in southern India (Injar) suggested a ratio of 47 males for 100 females.

Sexual selection

Thayer in his «Peacock in the Woods» (1907) suggested that the function of the ornate tail was camouflage

The colours of the peacock and the contrast with the much duller peahen were a puzzle to early thinkers. Charles Darwin wrote to Asa Gray that the «sight of a feather in a peacock’s tail, whenever I gaze at it, makes me sick!» as he failed to see an adaptive advantage for the extravagant tail which seemed only to be an encumbrance. Darwin developed a second principle of sexual selection to resolve the problem, though in the prevailing intellectual trends of Victorian Britain, the theory failed to gain widespread attention.

The American artist Abbott Handerson Thayer tried to show, from his own imagination, the value of the eyespots as disruptive camouflage in a 1907 painting.  He used the painting in his 1909 book Concealing-Coloration in the Animal Kingdom, denying the possibility of sexual selection and arguing that essentially all forms of animal colouration had evolved as camouflage. He was roundly criticised in a lengthy paper by Theodore Roosevelt, who wrote that Thayer had only managed to paint the peacock’s plumage as camouflage by sleight of hand, «with the blue sky showing through the leaves in just sufficient quantity here and there to warrant the author-artists explaining that the wonderful blue hues of the peacock’s neck are obliterative because they make it fade into the sky.»

In the 1970s a possible resolution to the apparent contradiction between natural selection and sexual selection was proposed. Amotz Zahavi argued that peacocks honestly signalled the handicap of having a large and costly train. However, the mechanism may be less straightforward than it seems – the cost could arise from depression of the immune system by the hormones that enhance feather development.

The ornate train is believed to be the result of sexual selection by the females. Males use their ornate trains in a courtship display: they raise the feathers into a fan and quiver them. However, recent studies have failed to find a relation between the number of displayed eyespots and mating success. Marion Petrie tested whether or not these displays signaled a male’s genetic quality by studying a feral population of peafowl in Whipsnade Wildlife Park in southern England. She showed that the number of eyespots in the train predicted a male’s mating success, and this success could be manipulated by cutting the eyespots off some of the male’s ornate feathers.

Although the removal of eyespots makes males less successful in mating, eyespot removal substantially changes the appearance of male peafowls. It is likely that females mistake these males for sub-adults, or perceive that the males are physically damaged. Moreover, in a feral peafowl population, there is little variation in the number of eyespots in adult males. It is rare for adult males to lose a significant number of eyespots. Therefore, females’ selection might depend on other sexual traits of males’ trains. The quality of train is an honest signal of the condition of males; peahens do select males on the basis of their plumage. A recent study on a natural population of Indian peafowls in the Shivalik area of India has proposed a «high maintenance handicap» theory. It states that only the fittest males can afford the time and energy to maintain a long tail. Therefore, the long train is an indicator of good body condition, which results in greater mating success. While train length seems to correlate positively with MHC diversity in males, females do not appear to use train length to choose males. A study in Japan also suggests that peahens do not choose peacocks based on their ornamental plumage, including train length, number of eyespots and train symmetry. Another study in France brings up two possible explanations for the conflicting results that exist. The first explanation is that there might be a genetic variation of the trait of interest under different geographical areas due to a founder effect and/or a genetic drift. The second explanation suggests that «the cost of trait expression may vary with environmental conditions,» so that a trait that is indicative of a particular quality may not work in another environment.

Fisher’s runaway model proposes positive feedback between female preference for elaborate trains and the elaborate train itself. This model assumes that the male train is a relatively recent evolutionary adaptation. However, a molecular phylogeny study on peacock-pheasants shows the opposite; the most recently evolved species is actually the least ornamented one. This finding suggests a chase-away sexual selection, in which «females evolve resistance to male ploys». A study in Japan goes on to conclude that the «peacocks’ train is an obsolete signal for which female preference has already been lost or weakened».

However, some disagreement has arisen in recent years concerning whether or not female peafowl do indeed select males with more ornamented trains. In contrast to Petrie’s findings, a seven-year Japanese study of free-ranging peafowl came to the conclusion that female peafowl do not select mates solely on the basis of their trains. Mariko Takahashi found no evidence that peahens expressed any preference for peacocks with more elaborate trains (such as trains having more ocelli), a more symmetrical arrangement, or a greater length. Takahashi determined that the peacock’s train was not the universal target of female mate choice, showed little variance across male populations, and, based on physiological data collected from this group of peafowl, do not correlate to male physical conditions. Adeline Loyau and her colleagues responded to Takahashi’s study by voicing concern that alternative explanations for these results had been overlooked, and that these might be essential for the understanding of the complexity of mate choice. They concluded that female choice might indeed vary in different ecological conditions.

A 2013 study that tracked the eye movements of peahens responding to male displays found that they looked in the direction of the upper train of feathers only when at long distances and that they looked only at the lower feathers when males displayed close to them. The rattling of the tail and the shaking of the wings helped in keeping the attention of females.

Breeding

Egg, Collection Museum Wiesbaden

Peacocks are polygamous, and the breeding season is spread out but appears to be dependent on the rains. Peafowls usually reach sexual maturity at the age of 2 to 3 years old. Several males may congregate at a lek site and these males are often closely related.  Males at lek appear to maintain small territories next to each other and they allow females to visit them and make no attempt to guard harems. Females do not appear to favour specific males. The males display in courtship by raising the upper-tail coverts into an arched fan. The wings are held half open and drooped and it periodically vibrates the long feathers producing a ruffling sound. The cock faces the hen initially and struts and prances around and sometimes turns around to display the tail. Males may also freeze over food to invite a female in a form of courtship feeding. Males may display even in the absence of females. When a male is displaying, females do not appear to show any interest and usually continue their foraging.

The peak season in southern India is April to May, January to March in Sri Lanka and June in northern India. The nest is a shallow scrape in the ground lined with leaves, sticks and other debris. Nests are sometimes placed on buildings and in earlier times have been recorded using the disused nest platforms of the white-rumped vultures. The clutch consists of 4–8 fawn to buff white eggs which are incubated only by the female. The eggs take about 28 days to hatch. The chicks are nidifugous and follow the mother around after hatching. Downy young may sometimes climb on their mothers’ back and the female may carry them in flight to a safe tree branch. An unusual instance of a male incubating a clutch of eggs has been reported.

Feeding

Peafowl are omnivorous and eat seeds, insects, fruits, small mammals and reptiles. They feed on small snakes but keep their distance from larger ones. In the Gir forest of Gujarat, a large percentage of their food is made up of the fallen berries of Zizyphus. Around cultivated areas, peafowl feed on a wide range of crops such as groundnut, tomato, paddy, chili and even bananas. Around human habitations, they feed on a variety of food scraps and even human excreta. In the countryside, it is particularly partial to crops and garden plants.

Mortality factors

Adult peafowl can usually escape ground predators by flying into trees. Large animals such as leopards, dholes, wolves, lions and tigers can sometimes ambush them however, and in some areas such as the Gir forest, peafowl are fairly common prey for such formidable predators. Foraging in groups provides some safety as there are more eyes to look out for predators. They are also sometimes hunted by large birds of prey such as the changeable hawk-eagle and rock eagle-owl. Chicks are somewhat more prone to predation than adult birds. Adults living near human habitations are sometimes hunted by domestic dogs or by humans in some areas (southern Tamil Nadu) for folk remedies involving the use of «peacock oil».

In captivity, birds have been known to live for 23 years but it is estimated that they live for only about 15 years in the wild.

Conservation and status

Indian peafowl are widely distributed in the wild across South Asia and protected both culturally in many areas and by law in India. Conservative estimates of the population put them at more than 100,000. Illegal poaching for meat, however, continues and declines have been noted in parts of India. Peafowl breed readily in captivity and as free-ranging ornamental fowl. Zoos, parks, bird-fanciers and dealers across the world maintain breeding populations that do not need to be augmented by the capture of wild birds.

Poaching of peacocks for their meat and feathers and accidental poisoning by feeding on pesticide treated seeds are known threats to wild birds. Methods to identify if feathers have been plucked or have been shed naturally have been developed as Indian law allows only the collection of feathers that have been shed.

In parts of India, the birds can be a nuisance to agriculture as they damage crops. Its adverse effects on crops, however, seem to be offset by the beneficial role it plays by consuming prodigious quantities of pests such as grasshoppers. They can also be a problem in gardens and homes where they damage plants, attack their reflections breaking glass and mirrors, perch and scratch cars or leave their droppings. Many cities where they have been introduced and gone feral have peafowl management programmes. These include educating citizens on how to prevent the birds from causing damage while treating the birds humanely.

In culture

Main article: Mayura (mythology)See also: Peacock Throne

Kartikeya seated on a peacock, 6th century, Badami temple

Prominent in many cultures, the peacock has been used in numerous iconic representations, including being designated the national bird of India in 1963. The peacock, known as mayura in Sanskrit, has enjoyed a fabled place in India since and is frequently depicted in temple art, mythology, poetry, folk music and traditions. A Sanskrit derivation of mayura is from the root mi for kill and said to mean «killer of snakes». Many Hindu deities are associated with the bird, Krishna is often depicted with a feather in his headband, while worshippers of Shiva associate the bird as the steed of the God of war, Kartikeya (also known as Skanda or Murugan). A story in the Uttara Ramayana describes the head of the Devas, Indra, who unable to defeat Ravana, sheltered under the wing of peacock and later blessed it with a «thousand eyes» and fearlessness from serpents. Another story has Indra who after being cursed with a thousand ulcers was transformed into a peacock with a thousand eyes.

In Buddhist philosophy, the peacock represents wisdom. Peacock feathers are used in many rituals and ornamentation. Peacock motifs are widespread in Indian temple architecture, old coinage, textiles and continue to be used in many modern items of art and utility.[20] A folk belief found in many parts of India is that the peacock does not copulate with the peahen but that she is impregnated by other means. The stories vary and include the idea that the peacock looks at its ugly feet and cries whereupon the tears are fed on by the peahen causing it to be orally impregnated while other variants incorporate sperm transfer from beak to beak. Similar ideas have also been ascribed to Indian crow species. In Greek mythology the origin of the peacock’s plumage is explained in the tale of Hera and Argus. The main figure of the Yazidi religion Yezidism, Melek Taus, is most commonly depicted as a peacock.[72][73] Peacock motifs are widely used even today such as in the logos of the US NBC and the PTV television networks and the Sri Lankan Airlines.

These birds were often kept in menageries and as ornaments in large gardens and estates. In medieval times, knights in Europe took a «Vow of the Peacock» and decorated their helmets with its plumes. In several Robin Hood stories, the titular archer uses arrows fletched with peacock feathers. Feathers were buried with Viking warriors and the flesh of the bird was said to cure snake venom and many other maladies. Numerous uses in Ayurveda have been documented. Peafowl were said to keep an area free of snakes. In 1526, the legal issue as to whether peacocks were wild or domestic fowl was thought sufficiently important for Cardinal Wolsey to summon all the English judges to give their opinion, which was that they are domestic fowl.

In Anglo-Indian usage of the 1850s, to peacock meant making visits to ladies and gentlemen in the morning. In the 1890s, the term «peacocking» in Australia referred to the practice of buying up the best pieces of land («picking the eyes») so as to render the surrounding lands valueless. The English word «peacock» has come to be used to describe a man who is very proud or gives a lot of attention to his clothing.

A golden peacock (in Yiddish, Di Goldene Pave) is considered by some as a symbol of Ashkenazi Jewish culture, and is the subject of several folktales and songs in Yiddish.

One of the most widely recognized of all bird species, the Indian Peafowl commonly ia kept in farms and gardens around the world.  The male’s spectacular plumage and long train formed by the upper tail coverts have made it a favorite in captivity. and it has been introduced in many parts of the world, reaching Europe as early as 450 BC. Released on Little Exuma, Bahamas in the 1950s, it has become established, where it is reported to be common but secretive and rarely seen.  However, its distinctive, loud and far carrying call often betrays its presence.  Interestingly, Little Exuma appears to contain the only established population pf Indian Peafowl in the Neotropics.

Fuentes: Wikipedia/eBird/xeno-canto/Neotropical Birds

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