The asities are a
family
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. Idea ...
of birds, Philepittidae, that are
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...
to
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...
. The asities consist of four
species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...
in two
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 ...
. The ''Neodrepanis'' species are known as sunbird-asities and were formerly known as false sunbirds.
[del Hoyo, J. Elliott, A. & Christie, D. (editors). (2003) ''Handbook of the Birds of the World. Volume 8: Broadbills to Tapaculos''. Lynx Edicions. ]
''Philepitta'' is now the type-genus of a new bird family, the Philepittidae, into which the asities of Madagascar have been placed.
Description
Asities are small forest birds with
sexually dichromic
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
plumage
Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...
and brightly coloured wattles around the eyes of the males. These wattles, which are most conspicuous during the breeding season, get their colour from arrays of
collagen fibres.
This method of pigmentation is unique in the animal kingdom. Several other features separate them from the broadbills, they possess twelve tail
feathers on extremely short (almost non-existent in the ''Philepitta'' species) tails, their syrinx is encased with a large bronchial ring and they have forked tongues adapted to nectivory.
[Hawkins, F. (2003) Family Philepittidae (Asities) pp. 94-105 in del Hoyo J., Elliott A. & Christie D.A. (2003) '']Handbook of the Birds of the World
The ''Handbook of the Birds of the World'' (HBW) is a multi-volume series produced by the Spanish publishing house Lynx Edicions in partnership with BirdLife International. It is the first handbook to cover every known living species of bird. ...
. Volume 8. Broadbills to Tapaculos'' Lynx Edicions, Barcelona They have a long outer
primary
Primary or primaries may refer to:
Arts, entertainment, and media Music Groups and labels
* Primary (band), from Australia
* Primary (musician), hip hop musician and record producer from South Korea
* Primary Music, Israeli record label
Work ...
which buzzes in flight, possibly used in signalling during courtship. The two genera are quite distinct.
Behavior and ecology
Diet and feeding
The major component of the diet of asities is
fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in partic ...
. A wide range of different fruit is taken by the family, and they are among the most important avian dispersers of seeds, as there are very few other frugivorous birds in the forests of Madagascar. They will also take
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs ...
s. The ''Neodrepanis'' sunbird-asities will take
nectar, but do so with a long tongue rather than inserting their curved bills far into flowers.
Breeding
Rainforest asities breed during the Malagasy
rainy season
The rainy season is the time of year when most of a region's average annual rainfall occurs.
Rainy Season may also refer to:
* ''Rainy Season'' (short story), a 1989 short horror story by Stephen King
* "Rainy Season", a 2018 song by Monni
* '' ...
, beginning just before the rains in September to November.
The velvet asity begins breeding slightly sooner in the north of its range. That species is the only one for which detailed information about breeding is available. It has a
polygynous
Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women.
Incidence
Polygyny is more widespread in Africa than in any o ...
breeding system, with males holding small territories or
leks where they display to passing females.
Nest building and raising the young is incubation solely by the females. There are reports of yellow-bellied sunbird-asities feeding young in the nest and recently
fledge
Fledging is the stage in a flying animal's life between hatching or birth and becoming capable of flight.
This term is most frequently applied to birds, but is also used for bats. For altricial birds, those that spend more time in vulnera ...
d chicks, so there is clearly some variation in breeding strategies in the family. The nests of the family are elaborate; pear-shaped woven structures hanging from branches, similar to those of broadbills, although uniquely amongst birds which weave nests the entrance to the nest is pushed created by pushing through the wall after constructed (instead of the usual scenario where the entrance is weaved into the fabric of the nest).
Status and conservation
One species, the
yellow-bellied sunbird-asity, is listed as
vulnerable
Vulnerable may refer to:
General
* Vulnerability
* Vulnerability (computing)
* Vulnerable adult
* Vulnerable species
Music
Albums
* ''Vulnerable'' (Marvin Gaye album), 1997
* ''Vulnerable'' (Tricky album), 2003
* ''Vulnerable'' (The Used album) ...
by
BirdLife International
BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding ...
and the
IUCN. It was once considered to be an endangered species, and even possibly extinct; however this was due to a lack of
ornithological surveys in its high-altitude range. Subsequent research has found it to be more abundant than previously suspected, although it is still considered threatened due to
habitat loss
Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
and fragmentation.
Schlegel's asity is considered near threatened; it has a highly fragmented distribution but numerous strongholds in inaccessible ravines.
Taxonomy and systematics
They were thought to have been related to the
pittas, hence the scientific name of the family, but a 1993 study suggested that they are actually just a subfamily of
Eurylaimidae.
The morphology of the
syrinx
In classical Greek mythology, Syrinx (Greek Σύριγξ) was a nymph and a follower of Artemis, known for her chastity. Pursued by the amorous god Pan, she ran to a river's edge and asked for assistance from the river nymphs. In answer, s ...
is very similar to the
Grauer's broadbill of Africa. Here they are considered traditionally as a separate family. Some authors have placed the
sapayoa of
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...
in the family, although it is now considered by many to be in its own family, the
Sapayoidae
The sapayoa or broad-billed sapayoa (''Sapayoa aenigma'') is a suboscine passerine found in lowland rainforests in Panama and north-western South America. As the epithet ''aenigma'' ("the enigma") implies, its relationships have long been elusi ...
.
Species
References
External links
*
Asities videoson the Internet Bird Collection
{{Taxonbar, from=Q756777
*
Tyranni
Taxa named by Richard Bowdler Sharpe
Endemic birds of Madagascar