Sri Lankan junglefowl
|Sri Lankan junglefowl|
|Male in Sinharaja Forest Reserve, Sri Lanka|
The Sri Lankan junglefowl (Gallus lafayettii), also known as the Ceylon junglefowl, is a member of the Galliformes bird order which is endemic to Sri Lanka, where it is the national bird. It is closely related to the red junglefowl (G. gallus), the wild junglefowl from which the chicken was domesticated. However, a whole-genome molecular study rather show that Sri Lankan junglefowl and grey junglefowl are genetically sister species than with the red junglefowl. Sri Lankan junglefowl and red junglefowl diverged about 2.8 million years ago whereas, time of divergence between the Sri Lankan junglefowl and grey junglefowl was 1.8 million years ago.
Evidence of introgressive hybridization from Sri Lanka junglefowl has also been established in domestic chicken. The specific name of the Sri Lankan junglefowl commemorates the French aristocrat Gilbert du Motier, marquis de La Fayette. In Sinhala, it is known as වළි කුකුළා (wali kukula) and in Tamil, it is known as இலங்கைக் காட்டுக்கோழி (ilaṅkaik kāṭṭukkōḻi).
|Cladogram showing the species in the genus Gallus.|
As with other junglefowl, the Sri Lankan junglefowl is strongly sexually dimorphic; the male is much larger than the female, with more vivid plumage and a highly exaggerated wattle and comb.
The male Sri Lankan junglefowl ranges from 66–72 cm (26–28 in) in length and 790–1,140 g (1.74–2.51 lb) in weight, essentially resembling a large, muscular rooster. The male has orange-red body plumage, and dark purple to black wings and tail. The feathers of the mane descending from head to base of spine are golden, and the face has bare red skin and wattles. The comb is red with a yellow centre. As with the green junglefowl, the cock does not possess an eclipse plumage.
The female is much smaller, at only 35 cm (14 in) in length and 510–645 g (1.124–1.422 lb) in weight, with dull brown plumage with white patterning on the lower belly and breast, ideal camouflage for a nesting bird.
The Sri Lankan junglefowl is most closely related to the grey junglefowl, though physically the male resembles the red junglefowl. Female Sri Lanka junglefowl are very similar to those of the grey junglefowl. Like the green junglefowl, Sri Lankan junglefowl are island species that have evolved side by side with their similarly stranded island predators and competitors. Uniquely complex anti-predator behaviors and foraging strategies are integral components in the long evolutionary story of the Sri Lankan junglefowl.
Females lay two to four eggs in a nest, either on the forest floor in steep hill country or in the abandoned nests of other birds and squirrels. Like the grey and green junglefowl, male Sri Lankan junglefowl play an active role in nest protection and chick rearing.
The reproductive strategy of this species is best described as facultative polyandry, in that a single female is typically linked with two or three males that form a pride of sorts. These males are likely to be siblings. The female pairs with the alpha male of the pride and nests high off the ground.
Her eggs are highly variable in colour, but generally are cream with a yellow or pink tint. Purple or brownish spots are common.
Occasionally, a female produces red eggs or blotched eggs.
The hen incubates her eggs, while the alpha male guards her nest from a nearby perch during the nesting season. The beta males remain in close proximity, and guard the nesting territory from intruders or potential predators, such as rival males, or snakes and mongooses. Sri Lankan junglefowl are unique amongst the junglefowl in the brevity of their incubation, which may be as short as 20 days as contrasted with the 21–26 days of the green junglefowl.
The chicks require a constant diet of live food, usually insects and isopods such as sowbugs and pillbugs. In particular, the juveniles of land crabs are also highly important to the growth and survivability of the juvenile and subadult Sri Lankan junglefowl. In captivity, this species is particularly vulnerable to a poultry disease caused by the bacteria Salmonella pullorum and other bacterial diseases common in domestic poultry.
The chicks, and to a slightly lesser extent the adults, are incapable of using vegetable-based proteins and fats. Their dietary requirements cannot be met with commercial processed food materials. As a result, they are exceedingly rare in captivity.
- BirdLife International (2016). "Gallus lafayettii". IUCN Red List of Threatened Species. 2016: e.T22679209A92807515. doi:10.2305/IUCN.UK.2016-3.RLTS.T22679209A92807515.en.
- Lawal, R.A.; et al. (2020). "The wild species genome ancestry of domestic chickens". BMC Biology. 18 (13): 13. doi:10.1186/s12915-020-0738-1. PMC 7014787. PMID 32050971.
- "Archived copy" (PDF). Archived from the original (PDF) on 2010-04-01. Retrieved 2014-10-13.CS1 maint: archived copy as title (link)
- Tiley, G.P.; Pandey, A.; Kimball, R.T.; Braun, E.L.; Burleigh, J.G. (2020). "Whole genome phylogeny of Gallus: introgression and data‑type effects". Avian Research. 11 (7). doi:10.1186/s40657-020-00194-w.
- del Hoyo, J. Elliott, A. and Sargatal, J. Handbook of the Birds of the World Lynx Edicions, Barcelona
- CRC Handbook of Avian Body Masses by John B. Dunning Jr. (Editor). CRC Press (1992), ISBN 978-0-8493-4258-5.
- International Chicken Polymorphism Map Consortium Wong, GK; et al. (2004). "A genetic variation map for chicken with 2.8 million single-nucleotide polymorphisms". Nature. 432: 717–722. doi:10.1038/nature03156. PMC 2263125. PMID 15592405.
- Grouw, Hein van; Dekkers, Wim; Rookmaaker, Kees (2017). "On Temminck's tailless Ceylon Junglefowl, and how Darwin denied their existence". Bulletin of the British Ornithologists' Club. 137 (4): 261–271. doi:10.25226/bboc.v137i4.2017.a3.