Double-banded Argus
Encyclopedia
A mysterious pheasant
, the Double-banded Argus, Argusianus bipunctatus, is known only from the portion of a single primary flight feather
. It was described in 1871 from this feather piece, found in a millinery shipment imported to London
.
Its origin was hypothesized to be from Java, Indonesia
or Tioman Island
of Malaysia, because of the Great Argus' absence from these locations. Parkes (1992) vehemently rejected the "species
" validity and argued that the Double-banded Argus almost certainly represents a mutant
form of the Great Argus
. The IUCN, following the precautionary principle
, lists this taxon
as extinct.
While the feather is indeed quite distinct, it represents a fairly simple divergence: The entirely asymmetrically-pattern vanes are instead near-symmetrical and both bear the darker brown shaftward area with innumerable whitish speckles. The shaft is thinner than usual and the feather would probably not have been useful for flight.
Nothing similar has come to notice ever since, and as the feather piece is not a composite of two feather halves glued together but a natural (albeit peculiar) specimen, a hoax or fake can be ruled out. Nonetheless all conjecture that has been built around the feather piece, all that can be said is that at some time around 1870 an argus pheasant was shot in an unknown location which bore at least one such feather. Even if this one known individual was the last remnant of a disappearing population, it is hard to believe that only a single feather would have been taken from an unusual specimen of a well-known, often-hunted, and conspicuous bird, and that this single feather would have been then transported elsewhere, to be bundled into a shipment of perfectly normal Great Argus feathers.
The feather is now housed in the British Natural History Museum. A photo of the specimen is in Fuller (2000:111).
Pheasant
Pheasants refer to some members of the Phasianinae subfamily of Phasianidae in the order Galliformes.Pheasants are characterised by strong sexual dimorphism, males being highly ornate with bright colours and adornments such as wattles and long tails. Males are usually larger than females and have...
, the Double-banded Argus, Argusianus bipunctatus, is known only from the portion of a single primary flight feather
Flight feather
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired feathers on the wings or tail of a bird; those on the wings are called remiges while those on the tail are called rectrices . Their primary function is to aid in the generation of both thrust and lift, thereby...
. It was described in 1871 from this feather piece, found in a millinery shipment imported to London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
.
Its origin was hypothesized to be from Java, Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
or Tioman Island
Tioman Island
Tioman Island is a small island located 32 km off the east coast of Peninsular Malaysia in the state of Pahang, and is some 39 km long and 12 km wide. It has eight main villages, the largest and most populous being Kampung Tekek in the north...
of Malaysia, because of the Great Argus' absence from these locations. Parkes (1992) vehemently rejected the "species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
" validity and argued that the Double-banded Argus almost certainly represents a mutant
Mutant
In biology and especially genetics, a mutant is an individual, organism, or new genetic character, arising or resulting from an instance of mutation, which is a base-pair sequence change within the DNA of a gene or chromosome of an organism resulting in the creation of a new character or trait not...
form of the Great Argus
Great Argus
The Great Argus, Argusianus argus is a brown-plumaged pheasant with a small blue head and neck, rufous red upper breast, black hair-like feathers on crown and nape, and red legs. The male is among the largest of all pheasants. He measures in total length, including a tail of , and weighs . It has...
. The IUCN, following the precautionary principle
Precautionary principle
The precautionary principle or precautionary approach states that if an action or policy has a suspected risk of causing harm to the public or to the environment, in the absence of scientific consensus that the action or policy is harmful, the burden of proof that it is not harmful falls on those...
, lists this taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
as extinct.
While the feather is indeed quite distinct, it represents a fairly simple divergence: The entirely asymmetrically-pattern vanes are instead near-symmetrical and both bear the darker brown shaftward area with innumerable whitish speckles. The shaft is thinner than usual and the feather would probably not have been useful for flight.
Nothing similar has come to notice ever since, and as the feather piece is not a composite of two feather halves glued together but a natural (albeit peculiar) specimen, a hoax or fake can be ruled out. Nonetheless all conjecture that has been built around the feather piece, all that can be said is that at some time around 1870 an argus pheasant was shot in an unknown location which bore at least one such feather. Even if this one known individual was the last remnant of a disappearing population, it is hard to believe that only a single feather would have been taken from an unusual specimen of a well-known, often-hunted, and conspicuous bird, and that this single feather would have been then transported elsewhere, to be bundled into a shipment of perfectly normal Great Argus feathers.
The feather is now housed in the British Natural History Museum. A photo of the specimen is in Fuller (2000:111).