Eye-ring on:
[Wikipedia]
[Google]
[Amazon]
The eye-ring of a bird is a ring of tiny feathers that surrounds the orbital ring, a ring of bare skin immediately surrounding a bird's eye. The eye-ring is often decorative, and its colour may contrast with adjoining plumage. The ring of feathers is sometimes incomplete, forming an eye arc. In the absence of a conspicuous eye-ring, the orbital ring of a bird is often referred to as the eye-ring.
The bare orbital ring may be hardened or fleshy, or may form an eye-
File:Cossypha caffra, juveniel, Pretoria, h.jpg,
The eye-ring of a bird is a ring of tiny feathers that surrounds the orbital ring, a ring of bare skin immediately surrounding a bird's eye. The eye-ring is often decorative, and its colour may contrast with adjoining plumage. The ring of feathers is sometimes incomplete, forming an eye arc. In the absence of a conspicuous eye-ring, the orbital ring of a bird is often referred to as the eye-ring.
The bare orbital ring may be hardened or fleshy, or may form an eye-wattle
Wattle or wattles may refer to:
Plants
*''Acacia sensu lato'', polyphyletic genus of plants commonly known as wattle, especially in Australian English
**''Acacia''
***Black wattle, common name for several species of acacia
***Golden wattle, ''A ...
. These are useful field marks in many bird species, and the eye-ringed flatbill
The eye-ringed flatbill (''Rhynchocyclus brevirostris'') is a species of bird in the family Tyrannidae, the tyrant flycatchers. It is found in Mexico, every Central American country, and Colombia.
Taxonomy and systematics
The eye-ringed flatb ...
, eye-ringed tody-tyrant
The eye-ringed tody-tyrant (''Hemitriccus orbitatus'') is a species of bird in the family Tyrannidae, the tyrant flycatchers. It is endemic to Brazil.
Taxonomy and systematics
The eye-ringed tody-tyrant has a complicated taxonomic history. I ...
and eye-ringed thistletail
The eye-ringed thistletail (''Asthenes palpebralis'') is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is endemic to central Peru.
Taxonomy and systematics
The eye-ringed thistletail was long treated a ...
are examples of species named for either of these. __NOTOC__
Function
Eye-rings are believed to convey various types of signals between individual birds. Some eye-rings appear only atsexual maturity
Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized ...
, while others suggest the individual's age or health status. Individual birds may be included or excluded from reproductive capability due to signals conveyed by the eye-ring. Red carotenoid
Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, cana ...
-based colors of the orbital rings of pheasants are known to be related to health.
The function of the white eye-rings in white-eyes
The white-eyes are a family, Zosteropidae, of small passerine birds native to tropical, subtropical and temperate Sub-Saharan Africa, southern and eastern Asia, and Australasia. White-eyes inhabit most tropical islands in the Indian Ocean, the ...
is unknown. It is suspected that they may serve to highlight infestations of small ectoparasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted str ...
s around the eyes. Untainted white eye-rings may consequently express vigorous health. In addition they may signal membership of a particular group or population, as different species and populations may have rings of differing colour, size, shape or completeness. These recognition signals could then play a role in reproductive isolation
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, ethology, behaviors and physiology, physiological processes critical for speciation. They prevent members of different species from producing offspring, or ensu ...
and speciation
Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...
.
Gallery
Robin-chat Robin-chat is a name given to a number of bird species:
* ''Cossypha
''Cossypha'' are small insectivorous birds, with most species called robin-chats. They were formerly in the thrush (bird), thrush family Turdidae, but are now more often treate ...
species, with a double ring of small feathers about the eye
File:Geothlypis tolmiei Hungry Horse MT 1, crop.jpg, Eye arcs above and below the eye of a male MacGillivray's warbler
MacGillivray's warbler (''Geothlypis tolmiei'') is a species of New World warbler. These birds are sluggish and heavy warblers, preferring to spend most of their time on, or near the ground, except when singing.
left, A MacGillivray's warbler ...
File:Glareola maldivarum - Beung Borapet, crop.jpg, Pratincole
The pratincoles or greywaders are a subfamily (Glareolinae) of birds which together with the coursers make up the family Glareolidae. They have short legs, very long pointed wings and long forked tails.
Description
Their most unusual feature for ...
with a complete dark orbital ring but partially contrasting white eye-ring
File:Killdeer and child, crop.JPG, The killdeer
The killdeer (''Charadrius vociferus'') is a large plover found in the Americas. Its shrill, two-syllable call is often heard, sounding like "kill deer". It was described and given its current scientific name in 1758 by Carl Linnaeus in the 1 ...
, one of many wader
245px, A flock of Red_knot.html" ;"title="Dunlins and Red knot">Dunlins and Red knots
Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflats in order to foraging, ...
s with a conspicuous red orbital ring
File:Anser erythropus -WWT Slimbridge, Gloucestershire, England -head-8a, crop.jpg, Bright yellow orbital ring in a lesser white-fronted goose
The lesser white-fronted goose (''Anser erythropus'') is a goose closely related to the larger greater white-fronted goose (''A. albifrons''). It breeds in the northernmost Palearctic, but it is a scarce breeder in Europe, with a reintroduction ...
File:Blackbird (Turdus merula) ♂ (51015122728).jpg, A male blackbird with distinct yellow orbital ring
See also
*Glossary of bird terms
The following is a glossary of common English language terms used in the description of birds—warm-blooded vertebrates of the Class (biology), class Aves and the Origin of birds, only living dinosaurs. Birds, who have and the ability to (ex ...
* Iris
Iris most often refers to:
*Iris (anatomy), part of the eye
* Iris (color), an ambiguous color term
*Iris (mythology), a Greek goddess
* ''Iris'' (plant), a genus of flowering plants
* Iris (given name), a feminine given name, and a list of peopl ...
* List of terms used in bird topography
The following is a list of terms used in bird topography:
Plumage features
* Back
* Belly
* Breast
* Cheek
* Chin
* Crest
* Crown
* Crown patch
* Ear-coverts
* Eye-ring
* Eyestripe (or eye line)
* Feather, see category: :Feathers
* Fla ...
* Sclerotic eye-ring
References
{{Feather-tracts Bird anatomy Feathers