Barn-owls (family Tytonidae) are one of the two
families
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideall ...
of
owl
Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...
s, the other being the
true owl
The true owls or typical owls (family Strigidae) are one of the two generally accepted families of owls, the other being the barn owls (Tytonidae). This large family comprises 230 living or recently extinct species in 24 genera. The typical owl ...
s or typical owls,
Strigidae
The true owls or typical owls (family Strigidae) are one of the two generally accepted families of owls, the other being the barn owls (Tytonidae). This large family comprises 230 living or recently extinct species in 24 genera. The typical owl ...
. They are medium to large owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful
talon
Talon or talons may refer to:
Science and technology
* Talon (anatomy), the claw of a bird of prey
* Brodifacoum, a rodenticide, also known as the brand Talon
* TALON (database), a database maintained by the US Air Force
* Talon, an anti-vehicle- ...
s. They also differ from the Strigidae in structural details relating in particular to the sternum and feet.
Barn-owls are a wide-ranging family, although they are absent from northern North America,
Sahara
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, photo_caption = The Sahara taken by Apollo 17 astronauts, 1972
, map =
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, location =
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n Africa, and large parts of Asia. They live in a wide range of habitats from
desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...
s to
forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
s, and from
temperate
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...
latitudes to the
tropics
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
. Within these habitats, they live near agricultural areas with high amounts of human activity. The majority of the 20 living species of barn-owls are poorly known. Some, like the
red owl
The red owl (''Tyto soumagnei'') is an owl in the barn owl family Tytonidae. It is also known as the Madagascar red owl, Madagascar grass-owl and Soumagne's owl. It is a rare resident of Madagascar that was virtually unknown from its discovery i ...
, have barely been seen or studied since their discovery, in contrast to the common barn-owl, which is one of the best-known owl species in the world. However, some subspecies of the common barn-owl possibly deserve to be separate species, but are very poorly known.
Five species of barn-owl are threatened, and some island species went
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
during the
Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togethe ...
or earlier (e.g., ''
Tyto pollens
''Tyto pollens'' is an extinct giant barn owl which lived in the Bahamas during the last Ice Age. Description
It is only known from the partial remains of three individuals which have been collected on the islands of Little Exuma (the site was mi ...
'', known from the fossil record of
Andros Island
Andros Island is an archipelago within the Bahamas, the largest of the Bahamian Islands. Politically considered a single island, Andros in total has an area greater than all the other 700 Bahamian islands combined. The land area of Andros consis ...
in the Bahamas, and possibly the basis for the mythical
chickcharney
The chickcharney (also known as the chickcharnie or chickcharnee) is a legendary creature in the folklore of Andros Island in the Bahama Islands. It is said to live in the forests, is furry or feathered, and about tall, with an ugly appearance r ...
). Barn-owls are mostly
nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
and generally non-
migratory, living in pairs or singly.
Taxonomy and systematics
Barn-owls consist of two extant subfamilies: the Tytoninae or ''Tyto'' owls (including the common
barn owl
The barn owl (''Tyto alba'') is the most widely distributed species of owl in the world and one of the most widespread of all species of birds, being found almost everywhere except for the polar and desert regions, Asia north of the Himalaya ...
) and the
Phodilinae
The bay owls (''Phodilus'') are a genus of Old World barn-owl
Barn-owls (family Tytonidae) are one of the two families of owls, the other being the true owls or typical owls, Strigidae. They are medium to large owls with large heads and char ...
or bay owls. The modern
genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
''Tyto'' and ''Phodilus'' are thought to have originated from a common ancestor from the Oligocene period.
It is believed the modern genus ''Tyto'' descended from large nocturnal birds in the West Indies during the Quaternary. The systematics of this group began with the discovery of ''Tyto ostologa'' (now extinct), whose remains were found in north-central Haiti. This discovery led to the finding of ''Tyto pollens, Tyto noeli,'' and ''Tyto riveroi'' in nearby cave deposits, all of which are now extinct and were also considered giant. The
Sibley-Ahlquist taxonomy unites the
Caprimulgiformes
Nightjars are medium-sized nocturnal or crepuscular birds in the family Caprimulgidae and order Caprimulgiformes, characterised by long wings, short legs, and very short bills. They are sometimes called goatsuckers, due to the ancient folk tal ...
with the owl
order
Order, ORDER or Orders may refer to:
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
* Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...
; here, barn-owls are a
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 subfamily botanical names with "-oideae", and zoologi ...
, Tytoninae. This is unsupported by more recent research (see
Cypselomorphae
Strisores ( ) is a clade of birds that includes the living families and orders Caprimulgidae (nightjars, nighthawks and allies), Nyctibiidae (potoos), Steatornithidae (oilbirds), Podargidae ( frogmouths), Apodiformes (swifts and hummingbird ...
), but the relationships of the owls in general are still unresolved.
Extant genera
Two extant genera are recognized:
* Genus ''
Tyto
''Tyto'' is a genus of birds consisting of true barn owls, grass owls and masked owls that collectively make up all the species within the subfamily Tytoninae of the barn owl family, Tytonidae.
Taxonomy
The genus ''Tyto'' was introduced in 1828 ...
'' – true barn-owls, grass owls and masked owls (17 species)
* Genus ''
Phodilus
The bay owls (''Phodilus'') are a genus of Old World barn-owls. The defining characteristics of bay owls are their smaller bodies, in comparison to other barn owls, and their U- or V-shaped faces. These owls can be found in South to Southeast As ...
'' –
bay owl
The bay owls (''Phodilus'') are a genus of Old World barn-owls. The defining characteristics of bay owls are their smaller bodies, in comparison to other barn owls, and their U- or V-shaped faces. These owls can be found in South to Southeast Asi ...
s (3 species)
Genus ''Tyto''
Some of the ''Tyto'' species that exist include the common barn owl (''Tyto alba''), the American barn owl (''Tyto furctata''), the Australian barn owl (''Tyto delicatula''), and the Eastern Barn Owl (''T. javanica''). Within each of these species, there are many subspecies. Of the common barn owl there are 10 subspecies: ''T. alba affinis, T. alba alba, T. alba erlangeri, T. abla ernesti, T. alba gracilirostris, T. alba guttata, T. alba hypermetra, T. alba javanica, T. alba schmitzi,'' and ''T. alba stertens.'' Of the American barn owl, there are 5 subspecies: ''T. furcata attempta, T. furcata furcata, T. furcata hellmayri, T. furcata pratincola, and T. furcata tuidara.'' Of the Australian barn owl, there are 4 subspecies: ''T. delicatula delicatula, T. delicatula interposita, T. delicatula meeki,'' and ''T. delicatula sumbaensis.''
The common barn owl (''T. alba'') can be found in Africa and parts of Asia, including Eurasia. The American barn owl (''T. furcata'') can be found from North to South America. Lastly, the Australian barn owl (''T. delicatula'') can be found in Australia, New Zealand, Polynesia, and Asia.
Genus ''Phodilus''
This genus includes the Oriental bay owls (''P. badius'')'','' Congo bay owls (''P. prigoginei''), and the Sri Lanka bay owls (''P. assimilis'').
Bay owls have a much smaller distribution than genus ''Tyto'', with Oriental bay owls (''P. badius'') found in India, Congo bay owls (''P. prigoginei'') found in Congo, and Sri Lanka bay owls (''P. assimilis'') found in Sri Lanka.
Extinct genera
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 in ...
of barn-owls goes back to the
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
, with the family eventually losing ground to the true owls after the radiation of
rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
s and owls during the
Neogene
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...
epoch. Two subfamilies are known only from the fossil record: the Necrobyinae and the Selenornithinae. At least four extinct genera of barn-owls have been described:
* Genus ''Nocturnavis'' (Late Eocene/Early Oligocene) – includes ''Bubo incertus''
* Genus ''Necrobyas'' (Late Eocene/Early Oligocene – Late Miocene, France) – includes ''Bubo arvernensis'' and ''Paratyto''
* Genus ''Selenornis'' (Late Eocene/Early Oligocene of Quercy, France) – includes ''Asio henrici''
* Genus ''Prosybris'' (Late Eocene/Early Oligocene of Quercy(?) – Early Miocene of France and Austria)
Placement unresolved
* Tytonidae gen. et sp. indet. "TMT 164" (Middle Miocene of Grive-Saint-Alban, France) - ''Prosybris''?
* Genus ''Palaeotyto'' (Late Eocene/Early Oligocene) from Quercy, France. Placement in this family is tentative, it may instead belong to the family
Sophiornithidae
The Sophiornithidae (literally "wisdom birds") are an extinct family of chicken-sized predatory birds that lived from the Paleocene to the Eocene periods of the Cenozoic, and were found primarily in Europe, and are thought to be primitive owls.
...
.
* Genus ''Palaeobyas'' (Late Eocene/Early Oligocene) from Quercy, France. Placement in this family is tentative, it may instead belong to the family
Sophiornithidae
The Sophiornithidae (literally "wisdom birds") are an extinct family of chicken-sized predatory birds that lived from the Paleocene to the Eocene periods of the Cenozoic, and were found primarily in Europe, and are thought to be primitive owls.
...
.
Former genera
The supposed "giant barn-owl" ''
Basityto'' from the Early Eocene of Grafenmühle (Germany) was actually a
crowned crane
A crowned crane is a bird of the genus ''Balearica'':
* Black crowned crane (''Balearica pavonina'')
* Grey crowned crane (''Balearica regulorum'')
Some authorities use the term "crowned crane" to refer generally to the genus ''Balearica''. Like ...
(''Balearica''); the presumed "Easter Island barn-owl", based on
subfossil
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 in ...
bones found on
Rapa Nui
Easter Island ( rap, Rapa Nui; es, Isla de Pascua) is an island and special territory of Chile in the southeastern Pacific Ocean, at the southeasternmost point of the Polynesian Triangle in Oceania. The island is most famous for its nearly ...
, has turned out to be a
procellarid; and the specimen originally described as the fossilized Pliocene ''Lechusa stirtoni'' was later determined to be recent remains of a modern-day American barn owl.
Description
The barn-owl's main characteristic is the heart-shaped
facial disc
In ornithology, the facial disc is the concave collection of feathers on the face of some birds—most notably owls—surrounding the eyes. The concavity of the facial disc forms a circular paraboloid that collects sound waves and directs those ...
, formed by stiff
feather
Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and a premier ...
s which serve to amplify and locate the source of sounds when hunting.
[
] Further adaptations in the wing feathers eliminate sound caused by flying, aiding both the hearing of the owl listening for hidden prey and keeping the prey unaware of the owl. Barn-owls overall are darker on the back than the front, usually an orange-brown colour, the front being a paler version of the back or mottled, although considerable variation is seen even within species.
Bay owls closely resemble the ''Tyto'' owls, but have a divided facial disc, ear tufts, and tend to be smaller.
References
External links
*
Barn owlson the Internet Bird Collection
{{Taxonbar, from=Q27112
Owls
*
Extant Eocene first appearances
Taxa named by Robert Ridgway