EEP Crowned pigeon number 4

EEP STUDBOOK CROWNED PIGEONS
6.1 Crowned Pigeons: Species or sub-species?
Scientists are not sure whether the three species are real species or sub-species to one species.
According to Goodwin (1983) a species can be defined as a number of individuals all of
which show more resemblance to each other than to other species, interbreed freely with each
other, and do not normally breed with members of another species’. Both in the wild and in
captivity, hybrids can be found. In the Siriwo River region of north-western New Guinea
Goura Victoria and Goura Cristata meet and hybridise (Goodwin, 1983). This paper
describes in short the position of crowned pigeons within the taxonomic system and the
history of the island of New Guinea to support the discussion whether there are three species
or three subspecies of crowned pigeons.
Taxonomic position of crowned pigeons
The class of birds (aves), within the vertebrates (vertebrata), consists of 34 orders, and
crowned pigeons belong to the order of pigeons and doves (Columbiformes). This order, on its
turn, originally comprised three families: the sandgrouse (Pteroclidadae), the dodos
(Raphinae), which became extinct during the 17th and 18th centuries (Harrison (ed.), 1978)
and the pigeons (Columbidae). The Columbidae comprises 4 subfamilies with a total of 43
genera and some 255 species of pigeons. They are found in most parts of the world except for
polar and subpolar regions and some oceanic islands. The term ‘pigeon’ is sometimes used to
denote the larger species, in contrast to the smaller species which are known as ‘doves’, but
the terms are not consistently used and are not based on any real biological distinction
(Goodwin, 1983). Pigeons are unique among birds in that their young are fed on a nutritious
substance known as‘crop-milk’ (Baptista, et al., 1997).
Group Vertebrata Vertebrates
Class Aves Birds
Sub-class Neornithes True birds
Superorder Neognathae Typical Birds
Order Columbiformes Sandgrouse and Pigeons
Sub-Order Columbae Pigeons, Dodos and Solitaires
Family Columbidae Pigeons, Doves
Sub-family Gourinae Crowned pigeons
Genus Goura Crowned pigeons
Species (e.g.) cristata Common crowned pigeon
Sub-species (e.g.) Minor Lesser common crowned pigeon
The four subfamilies are the Columbinae (including typical pigeons and doves), Treroninae
(containing fruit pigeons and fruit doves), the Gourinae (containing only crowned pigeons)
and the Didunculinae (contains but the one species of tooth-billed pigeon - Didunculus
strigirostris) (Goodwin, 1983).
The subfamily of Gourinae consists of only one genus: the Goura, firstly described by
Stephens, 1819 (Baptista, et al., 1997). A genus is a group of species that are closely related
to each other and all of whose members appear to be more closely akin to other species within
the same genus than they are to any other species of other genera (Goodwin, 1983).
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