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LEUCISM , LEUCISTIC , LEUCISTIK
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L,leucism,leucistic.leucistik,t-rec,tugumuda reptiles
community,kse,komunitas satwa eksotik,sahabat si komo,chloe ardella raisya
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leucism,hewan leucistik,binatang leucistic,binatang leucism,binatang
leucistik,mamalia leucistic,mamalia leucism,mamalia leucistik,satwa
leucistic,satwa leucistik,satwa leucism,burung leucistic,burung leucism,burung
leucistik,reptil leucistic,reptil leucistik,reptil leucism,ular leucistic,ular
leucism,ular leucistik ,Herpetofauna, herpetology, biodiversity,keanekaragaman
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reptiles community,kse,komunitas satwa eksotik,sahabat si komo,on line,chloe
ardella raisya putri kamarsyah,priankaputri,aldhika budi pradanam,semarang
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Leucistic or leucism
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Link chloepedia :
Herpetofauna 1
herpetofauna 2
herpetologi 1
herpetologi 2
herpetologi 3
herpetologi 4
herpetologi 5
herpetologi 6
amelanistic-amelanistik-amel-amelanism-1
amelanistic-amelanistik-amel-amelanism-2
metode penelitian herpetofauna-1
metode penelitian herpetofauna-2
metode penelitian herpetofauna-3
metode penelitian herpetofauna-4
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Leucism (/ˈljuːkɪzəm/;[1] or /ˈluːsɪzəm/[2][3]) is a
condition in which there is partial loss of pigmentation in an animal resulting in white, pale, or
patchy coloration of the skin, hair, feathers, scales or cuticle, but not the
eyes.[1] Unlike albinism, it is caused by a reduction in
multiple types of pigment, not just melanin. Leucism;leucistic/leucistik
(/ ljuːkɪzəm /; [1] atau / luːsɪzəm /
[2] [3]) adalah suatu kondisi di mana ada hilangnya sebagian dari pigmentasi
pada hewan yang menghasilkan warna putih, pucat, atau warna tambal sulam dari
kulit, rambut, bulu , sisik atau kutikula, tetapi tidak pada mata. [1] Tidak seperti albinisme, hal itu
disebabkan oleh penurunan beberapa jenis pigmen, bukan hanya melanin.
Leucism (occasionally spelled leukism)
is a general term for the phenotype resulting from defects in pigment celldifferentiation and/or migration from
the neural crest to skin, hair, or feathers during development. This results in either the entire
surface (if all pigment cells fail to develop) or patches of body surface (if
only a subset are defective) having a lack of cells capable of making pigment. Leucism/leucistic/leucistik (kadang-kadang
dieja leukism) adalah istilah umum untuk fenotipe yang dihasilkan dari
kerusakan cell differentiation pigmen dan / atau migrasi dari puncak saraf pada
kulit, rambut, atau bulu selama pengembangan. Hal ini menyebabkan baik seluruh
permukaan (jika semua sel pigmen gagal berkembang ) atau patch dari permukaan
tubuh (jika hanya subset atau cacat) menyebabkan
sel kurang mampu membuat pigmen.
Since all pigment cell-types differentiate from the same multipotent precursor cell-type, leucism can cause
the reduction in all types of pigment. This is in contrast to albinism, for which leucism is often mistaken.
Albinism results in the reduction ofmelanin production only, though the melanocyte (or melanophore) is still present. Thus in species
that have other pigment cell-types, for example xanthophores, albinos are not entirely white, but
instead display a pale yellow colour. Karena semua pigmen jenis-sel membedakan dari
multipoten prekursor sel-jenis yang sama, leucism dapat menyebabkan pengurangan
semua jenis pigmen. Hal ini berbeda dengan albinisme, yang menyebabkan leucism/leucistic/leucistik sering dianggap keliru. Hasil albinisme dalam pengurangan melanin
produksi saja, meskipun melanosit (atau melanophore) masih ada. Jadi dalam spesies
yang memiliki pigmen sel-jenis lainnya, misalnya xanthophores, albino tidak
sepenuhnya putih, melainkan menampilkan warna kuning pucat.
More common than a complete absence of pigment cells is localized or
incomplete hypopigmentation, resulting in irregular patches of
white on an animal that otherwise has normal colouring and patterning. This
partial leucism is known as a "pied" or "piebald" effect; and the ratio of white
to normal-coloured skin can vary considerably not only between generations, but
between different offspring from the same parents, and even between members of
the same litter. This is notable in horses,cows, cats, dogs,
the urban crow[4] and the ball python[5] but is also found in many other
species. Lebih
umum dari sel pigmen tidak lengkap
terlokalisir atau hipopigmentasi tidak lengkap, sehingga patch teratur warna putih
pada hewan yang dinyatakan memiliki pewarnaan yang normal dan pola. leucism
parsial ini dikenal sebagai "pied" atau efek
"belang-belang"; dan rasio putih untuk kulit normal berwarna dapat
bervariasi tidak hanya antar generasi, tetapi antara keturunan yang berbeda
dari orang tua yang sama, dan bahkan antara anggota dari keturunan yang
sama. Hal ini penting pada kuda, sapi,
kucing, anjing, burung gagak urban[4] dan ball python [5] tetapi juga ditemukan
pada banyak spesies lainnya.
A further difference between albinism and leucism is in eye colour. Due to the lack of melanin production
in both the retinalpigmented epithelium (RPE) and iris, those affected by albinism typically have red eyes due
to the underlying blood vessels showing through. In contrast, most leucistic
animals have normally coloured eyes. This is because the melanocytes of the RPE
are not derived from the neural crest, instead an outpouching of the neural tube generates the optic cup which, in turn, forms the retina. As these cells are from an
independent developmental origin, they are typically unaffected by the genetic
cause of leucism.
Perbedaan lainnya antara albinisme dan leucism dalam warna mata. Karena kurangnya produksi melanin di kedua epitel retinalpigmented (RPE) dan iris, mereka yang terkena albinisme biasanya memiliki mata merah karena pembuluh darah yang mendasari nya . Sebaliknya, sebagian besar hewan leucistic biasanya berwarna mata seperti biasanya . Hal ini karena melanosit dari RPE tidak berasal dari neural crest, bukan sebuah outpouching dari tabung saraf yang menghasilkan cangkir optik yang, pada gilirannya, membentuk retina. Sepertinya sel-sel ini dari asal perkembangan independen, mereka biasanya tidak terpengaruh oleh penyebab genetik leucism/leucistic/leucistik.
Gen itu, ketika bermutasi, dapat menyebabkan leucism/leucistic/leucistik termasuk, c-kit, [6] MITF [7] dan EDNRB. [8]
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Leucism/leucistic/leucistik
In leucistic birds, affected plumage lacks melanin
pigment due to the cells responsible for melanin production being absent. This
results in a white feathers, unless the normal plumage colour also comprises
carotenoids (e.g. yellows), which remain unaffected by the condition. Although
leucism is inherited, the extent and positioning of the white colouration can
vary between adults and their young, and can also skip generations if leucistic
genes are recessive. Pada burung leucistic/lucistic/leucistik, bulu yang terkena
kekurangan pigmen melanin karena sel-sel yang bertanggung jawab untuk produksi
melanin absen/hilang . Hal ini menghasilkan bulu putih, kecuali warna bulu yang
normal juga terdiri karotenoid (mis kuning), yang tetap tidak terpengaruh oleh
kondisi tersebut. Meskipun leucism diwariskan, tingkat dan posisi dari warna
putih dapat bervariasi antara dewasa dan anak-anak mereka, dan juga dapat
melewati generasi jika gen leucistic adalah resesif.
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Leucisim
is often mistaken for albinism, but they are two very different conditions. So
next time you see an animal you think is albino, look to see if it is only
mostly white and, importantly, take a look at the eyes. Leucisim/leucistic/leucistik sering keliru
untuk albinisme, tetapi mereka adalah dua kondisi yang sangat berbeda. Jadi
lain kali Anda melihat binatang Anda berpikir adalah albino, lihat apakah itu
hanya sebagian besar putih dan yang penting, lihatlah matanya.
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Leucism, or leukism, is an abnormal plumage condition caused by a genetic mutation that prevents pigment, particularly melanin, from being properly deposited on a bird’s feathers. As a result, the birds do not have the normal, classic plumage colors listed in field guides, and instead the plumage have several color changes, including: Leucism/leucistic/leucistik, atau leukism, adalah kondisi bulu abnormal yang disebabkan oleh mutasi genetik yang mencegah pigmen, terutama melanin, dari biasanya diendapkan pada bulu burung. Akibatnya, burung tidak normal, warna bulu klasik yang tercantum dalam panduan lapangan, dan bukannya bulu yang memiliki beberapa perubahan warna, termasuk:
·
White patches where the bird should not have any
·
Paler overall plumage that looks faint, diluted or bleached
·
Overall white plumage with little or no color discernable
The degree of leucism, including the brightness of the white and the
extent of pigment loss, will vary depending on the bird’s genetic makeup. Birds
that show only white patches or sections of leucistic feathers – often in
symmetrical patterns – are often called pied or piebald birds, while birds with fully
white plumage are referred to as leucistic birds.
• Bercak putih di mana burung tidak senya harus memilikinya
• Paler bulu keseluruhan yang terlihat samar, diencerkan atau dikelantang
• Secara keseluruhan bulu putih dengan sedikit atau tanpa warna discernable
Tingkat leucism, termasuk kecerahan putih dan besarnya kehilangan pigmen, akan bervariasi tergantung pada genetik burung. Burung yang menunjukkan patch hanya putih atau bagian dari bulu leucistic - sering dalam pola simetris - sering disebut burung pied atau belang, sementara burung dengan bulu sepenuhnya putih disebut burung sebagai leucistic/leucism/leucistik.
How to Identify Leucistic
Birds
While
leucistic birds will show irregular plumage coloration, it is still possible to
identify the birds easily. Many birds with leucism still show a faint wash of
color in recognizable patterns on their feathers, even though the color may not
be as strong as would be typical. Of course, piebald leucistic birds still show
other colors and only have patches of white feathers, but their plumage can
easily be used for identification aside from those feathers.
Cara Mengidentifikasi Leucistic Birds
Sementara burung leucistic/leucistik/leucism akan menunjukkan warna bulu tidak teratur , masih mungkin untuk mengidentifikasi burung dengan mudah. Banyak burung dengan leucism masih menunjukkan sapuan samar warna dalam pola yang dikenali pada bulu mereka, meskipun warna mungkin tidak sekuat sebagai tipikal . Tentu saja, burung belang leucistic masih menunjukkan warna lain dan hanya memiliki patch dari bulu putih, tapi bulu mereka dapat dengan mudah digunakan untuk identifikasi
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Leucism and Albinism in Birds
The ornithological literature is quite
confusing regarding definitions of leucism and various states of albinism.
Whereas recent ornithological texts define albinism (e.g., Welty and Baptista
1988, Gill 1990, Clark 2001), none refers specifically to leucism. Thomson
(1964) states that leucism “results from varying degrees of dilution of normal
pigmentation.”
Leucism dan Albinisme di Burung
Literatur ornitologi cukup membingungkan mengenai definisi leucism/leucistic/leucistik dan berbagai state dari albinisme. Sedangkan teks ornitologi baru-baru ini mendefinisikan albinisme (misalnya, Welty dan Baptista 1988, Gill 1990, Clark 2001), tidak mengacu khusus untuk leucism. Thomson (1964) menyatakan bahwa leucism "hasil dari berbagai tingkat pengenceran pigmentasi normal."
In a review of albinism in British
birds, Sage (1962) referred to leucistic individuals “in which the normal
pattern and colour of the plumage is discernable but very pale or washed out in
appearance” and (citing Hutt 1949) distinguished this dilution of all pigments
from albinism, which affects melanin but not necessarily the carotenoid
pigments. Lucas and Stettenheim (1972) point out that a genetically complete
albino could still have highly colored feathers if a pigment other than melanin
were present.
Dalam review albinisme pada burung Inggris, Sage (1962) sebutkan individu leucistic/leucism/leucistik "di mana pola normal dan warna bulu yang discernable tapi sangat pucat atau wash dalam penampilan" dan (mengutip Hutt 1949) dibedakan pengenceran semua pigmen dari albinisme, yang mempengaruhi melanin tetapi belum tentu pigmen karotenoid. Lucas dan Stettenheim (1972) menunjukkan bahwa genetik albino lengkap masih masih sangat berwarna pada bulu jika pigmen selain melanin juga hadir.
According to these authors, leucism is
caused not by a lack of pigment, but by a reduced deposition of pigment in the
feathers. Several of these references refer further to partial albinism as the
lack of melanin from part of the plumage, either symmetrically or
asymmetrically (Gross 1965, Lucas and Stettenheim 1972, Clark 2001).
Menurut para penulis ini, leucism/leucistic/leucistik tidak disebabkan oleh kurangnya pigmen, tetapi oleh deposisi berkurangnya pigmen di bulu. Beberapa referensi ini merujuk lebih lanjut untuk albinisme parsial sebagai kurangnya melanin dari bagian bulu, baik secara simetris atau asimetris (Gross 1965, Lucas dan Stettenheim 1972, Clark 2001).
Harrison (1963) made a different
distinction, stating that leucistic individuals have melanin in the body,
giving dark eyes and colored soft parts, but the melanin does not enter the
feather structure and the plumage is white, whereas albinistic individuals lack
melanin in the body as well as the plumage.
Harrison
(1963) membuat perbedaan yang berbeda, yang menyatakan bahwa individu
leucistic/leucism/leucistik memiliki melanin dalam tubuh, memberikan mata gelap
dan berwarna di bagian lembut, tapi melanin tidak masuk struktur bulu dan bulu
berwarna putih, sedangkan individu albinistic kekurangan melanin dalam tubuh
serta bulu tersebut.
Other recent authors follow this
“all-or-none” definition of albinism and believe that a bird with any amount of
abnormal white in the plumage, but with dark eyes, would be leucistic (e.g.
Jehl 1985, Cooke and Buckley 1987, Lawrence 1989).
penulis lainnya mengikuti "semua-atau-tidak"dari definisi albinisme dan percaya bahwa burung dengan jumlah putih yang abnormal dalam bulu, tapi dengan mata gelap, akan leucistic/leucism/leucistik (misalnya Jehl 1985, Cooke dan Buckley tahun 1987, Lawrence 1989 ).
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The different
types of albinism all have to do with the body’s inability to produce melanin,
leading to white, gray, or cream-colored hair and skin (but not necessarily red
eyes). Leucism occurs when color pigments are produced in a lower amount than
normal, and normal skin, fur, or feather patterns and textures remain. Berbagai jenis albinisme semua harus dilakukan
dengan ketidakmampuan tubuh untuk memproduksi melanin, menyebabkan rambut
putih, abu-abu, atau berwarna krim dan
kulit (tapi mata tidak selalu merah). Leucism/leucistic/leucistik terjadi ketika pigmen warna diproduksi dalam
jumlah yang lebih rendah dari normal, dan kulit, bulu, atau pola bulu normal
dan tekstur tetap.
Isabellinism
happens when normally dark-pigmented areas develop as a sort of washed-out
grayish-yellow, and it’s supposedly named for an archduchess who refused to
remove her underwear for three years.
Isabellinism terjadi ketika daerah yang biasanya berpigmen gelap berkembang sebagai semacam wash-out kuning keabu-abuan
Isabellinism terjadi ketika daerah yang biasanya berpigmen gelap berkembang sebagai semacam wash-out kuning keabu-abuan
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Leucistic
individuals produce melanin as normal, but the deposition of the pigments is
affected - so eye and bill/leg colours tends to be unaffected, but the colour
of feathers (or hair) can be. individu Leucistic/leucism/leucistik memproduksi melanin seperti biasa, tapi
pengendapan pigmen mempengaruhi - sehingga mata dan warna bill / kaki cenderung
tidak terpengaruh, tapi warna bulu (atau rambut) bisa.
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Leucism is a rare genetic
mutation where two recessive genes produce a white phenotype or pale
appearance. Leucism/leucistik/leucistic adalah mutasi genetik yang langka di mana dua
gen resesif menghasilkan fenotipe putih atau penampilan pucat.
Albinism: occurs when the body does
not possess any pigmentation. It’s characterised by pink eyes.
Leucism: Is the result of an recessive
allele that causes a reduction in pigmentation. Leucism affects all types
of pigmentations in the body.
Albinisme: terjadi ketika tubuh tidak memiliki
pigmentasi apapun. Ini ditandai dengan mata merah muda.
Leucism/leucistic/leucistik : Apakah hasil dari
alel resesif yang menyebabkan penurunan pigmentasi. Leucism mempengaruhi semua
jenis pigmentasi dalam tubuh.
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Leucism is a
condition in which there is partial loss of pigmentation in an animal resulting
in white, pale, or patchy coloration of the skin, hair, feathers, scales or
cuticle, but not the eyes. Unlike albinism, it is caused by a reduction in
multiple types of pigment, not just melanin.[1]
Leucism/leucistic/leucistik adalah suatu kondisi di mana ada hilangnya sebagian dari pigmentasi pada hewan menghasilkan putih, pucat, atau tambal sulam warna kulit, rambut, bulu, sisik atau kutikula, tetapi tidak pada mata. Tidak seperti albinisme, hal itu disebabkan oleh penurunan beberapa jenis pigmen, bukan hanya melanin. [1]
Leucism/leucistic/leucistik adalah suatu kondisi di mana ada hilangnya sebagian dari pigmentasi pada hewan menghasilkan putih, pucat, atau tambal sulam warna kulit, rambut, bulu, sisik atau kutikula, tetapi tidak pada mata. Tidak seperti albinisme, hal itu disebabkan oleh penurunan beberapa jenis pigmen, bukan hanya melanin. [1]
Leucistic Owls
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Leucism is a genetic mutation that prevents melanin and
other pigments from being deposited normally on feathers, resulting in pale or
muted colors on the entire bird.
Leucism/leucistic/leucistik adalah mutasi genetik yang mencegah melanin dan pigmen lainnya disimpan biasanya pada bulu, sehingga warna pucat atau diredam pada seluruh burung.
In this case
the bird would be considered leucistic because the mutation only applies to
depositing melanin in the feathers, not the absence of melanin in the body. Dalam hal ini burung akan dianggap leucistic /leucism/leucistik
karena mutasi hanya berlaku untuk melanin dalam bulu, tidak adanya melanin
dalam tubuh.
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- Leucism is also a genetic mutation.
Leucistic birds have dilute, paler/ whitish plumage overall. A faint
pattern may be visible. Leucism is also uncommon, but is more common that
albinism.
· Leucism/leucistic/leucistik juga mutasi genetik. burung Leucistic memiliki bulu bwerwarna encer, pucat / keputihan secara keseluruhan. Pola samar dapat terlihat. Leucism juga jarang, tetapi lebih sering terjadi pada albinisme .
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Leucistic snakes have no
melanophores (dark pigment cells), no xanthophores (yellow pigment cells) and
only very limited amounts of iridophores (reflective pigment cells) this is why
their skin appears white. The eyes get there colour from cells that migrate
from the neural tube and not the neural crest (where the body colour cells
migrates from). It is because of this independent developmental origin that the
eyes are typically unaffected by the genetic cause of Leucism.
ular Leucistic/leucism/leucistik tidak memiliki melanophores (sel pigmen gelap), tidak ada xanthophores (sel pigmen kuning) dan hanya jumlah yang sangat terbatas dari iridophores (sel pigmen reflektif) ini mengapa kulit mereka tampak putih. Warna Mata dari sel-sel yang bermigrasi dari tabung saraf dan tidak neural crest (di mana sel-sel warna tubuh bermigrasi dari). Hal ini karena asal perkembangan independen hingga mata biasanya tidak terpengaruh oleh penyebab genetik leucism.
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Leucistic
Reptiles
- Medically defined this is a defect
in the skin, not the pigment cells. Classical leucism is caused by a
faulty gene, or set of genes, that causes the skin to be unable to support
pigment cells
- Leucicism is a naturally occurring
pigmentation morph. True leucisticanimals are completely white without any
hint of patterning or pigmentation. They also have blue eyes,
whereas Albino animals will have red eyes
- White animals are still able to be
produced by mixing several morphs that remove different color
pigmentation. If you remove the yellow, red, and black, you will end up
with the white appearance as well. Patternless morphs will improve the
“white” appearance of the animal so you can get nearly as pure white as a
true leucistic, but they will have black eyes
· Secara medis didefinisikan ini adalah cacat pada kulit, tidak pada sel-sel pigmen. leucism klasik disebabkan oleh gen yang rusak, atau set gen, yang menyebabkan kulit menjadi tidak dapat mendukung sel pigmen
· • Leucicism/leucistic/leucistik adalah pigmentasi morph alami. Leucistic animals benar-benar putih tanpa petunjuk dari pola atau pigmentasi. Mereka juga memiliki mata biru, sedangkan hewan Albino akan memiliki mata merah
· • hewan Putih masih bisa diproduksi dengan mencampur beberapa morphs yang menghapus pigmentasi warna yang berbeda. Jika Anda menghapus kuning, merah, dan hitam, Anda akan berakhir dengan penampilan putih juga. morphs berpola akan meningkatkan penampilan "putih" hewan sehingga Anda bisa mendapatkan hampir putih bersih sebagai benar benar leucistic , tetapi mereka akan memiliki mata hitam
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Leucicism is a naturally
occuring pigmentation morph. True leucistic animals are completely white
without any hint of patterning or pigmentation. They also have blue eyes. So it
will always mean white with blue eyes.
Leucicism/leucistic/leucistik adalah pigmentasi morph yang terjadi secara alami. hewan leucistic benar-benar putih tanpa petunjuk dari pola atau pigmentasi. Mereka juga memiliki mata biru. Sehingga akan selalu berarti putih dengan mata biru. In some species (especially lizards) true leucistic genes have not yet been discovered. White animals are still able to be produced by mixing several morphs that remove different color pigmentations. If you remove the yellow, red, and black, you will end up with the white appearance as well. Patternless morphs will improve the "white" appearance of the animal so you can get nearly as pure white as a true leucistic.
Dalam beberapa spesies (terutama kadal) gen yang benar benar leucistic/leucism/leucistik belum ditemukan. hewan putih masih bisa diproduksi dengan mencampur beberapa morphs yang menghapus pigmentasi warna yang berbeda. Jika Anda menghapus kuning, merah, dan hitam, Anda akan berakhir dengan penampilan putih juga. morphs berpola akan meningkatkan penampilan "putih" hewan sehingga Anda bisa mendapatkan hampir putih bersih sebagai benar benar leucistic.
In bearded dragons the true leucicism has not yet been discovered (as far as I know). There are "white" bearded dragons that have been dubbed leucistic but these are not really true leucistic. You can tell by the lack of blue eyes. But although the "leucistic" animals sold are fake leucistics, they are still beautiful and white. The same is true for "leucistic" leopard geckos.
Dalam bearded dragon yang benar benar leucicism/leucistic/leucistik belum ditemukan (sejauh yang saya tahu). Ada bearded dragon "putih" yang telah dijuluki leucistic tetapi ini tidak benar benar leucistic. Anda dapat tahu oleh kurangnya mata biru. Tapi meskipun hewan "leucistic" yang dijual adalah leucistics palsu, mereka masih cantik dan putih. Hal yang sama berlaku untuk leopard gecko "leucistic".
True leucicism is much more common in snakes. Leucicism has been discovered in texas rat snakes and more recently in ball pythons as well as some other species.
Yang benar Benar leucicism/leucistic/leucistik jauh lebih umum di ular. Leucicism telah ditemukan di ular tikus texas dan di ball serta beberapa spesies lainnya.
https://answers.yahoo.com/question/index?qid=20090709193837AACcLUF
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Leucism is a condition in which pigmentation is reduced but not
entirely absent, as in albinism.
Leucism/leucistic/leucistik adalah suatu kondisi di mana pigmentasi berkurang tapi tidak sepenuhnya absen/hilang, seperti di albinisme
Leucism/leucistic/leucistik adalah suatu kondisi di mana pigmentasi berkurang tapi tidak sepenuhnya absen/hilang, seperti di albinisme
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2)LEUKISM
(LEUCISM)- medically defined this is a defect in the skin, not the pigment
cells. There are other derangements of pigment that can cause a whitening
effect, but they are not classical leukism. Classical leukism is caused by a
faulty gene, or set of genes, that causes the skin to be unable to support
pigment cells.
2) LEUKISM (leucism) /leocistic/leucistik – definisi medis ini adalah cacat pada kulit, tidak di sel-sel pigmen. Ada derangements lain dari pigmen yang dapat menyebabkan efek pemutihan, tetapi mereka tidak leukism klasik. leukism klasik disebabkan oleh gen yang rusak, atau set gen, yang menyebabkan kulit menjadi tidak dapat mendukung sel pigmen.
2) LEUKISM (leucism) /leocistic/leucistik – definisi medis ini adalah cacat pada kulit, tidak di sel-sel pigmen. Ada derangements lain dari pigmen yang dapat menyebabkan efek pemutihan, tetapi mereka tidak leukism klasik. leukism klasik disebabkan oleh gen yang rusak, atau set gen, yang menyebabkan kulit menjadi tidak dapat mendukung sel pigmen.
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Leucistic
Berbeda dengan albino yang kekurangan pigmen melanin, leucistic adalah
kelainan pada pigmen yaitu kekurangan jumlah semua jenis pigmen sehingga
warnanya cenderung putih bukan kekuningan seperti albino.
Leucistic parsial- (Mosaic)
Ketika leucistic hanya terjadi pada beberapa bagian kulit (atau bulu)
saja, maka disebut sebagai pied, atau dalam dunia SG disebut juga sebagai
Mosaic
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Leucistic
Memiliki bulu
berwarna putih yang solid tanpa garis di tubuh dan di telinganya. Leucitic
memiliki mata berwarna hitam. Sugar Glider jenis ini merupakan Sugar Glider
dengan gen resesif sehingga harus dipasangkan dengan Sugar Glider lain dengan
gen resesif yang sama agar dapat mereproduksi leucistic.
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White (also called Leucistic)
Commonly known as leucistic, the phenotype is d/d, non-melanoid, non-albino and non-axanthic. Here's a picture of a large adult female. Notice the black eyes and small number of melanophores on the head and back which indicate that it is not an albino. White axolotls with black eyes are not albino. While d/d prevents the axolotl's pigment cells from migrating off the top of the animal, this does not necessarily mean that all leucistics will possess colour cells on the the head and back - look at the eyes to be certain. Putih (juga disebut Leucistic)
Umumnya dikenal sebagai leucistic/leucistik/leucism , fenotipe adalah d / d, non-melanoid, non-albino dan non-Axanthic. Berikut adalah gambar dari betina dewasa besar. Perhatikan mata hitam dan sejumlah kecil melanophores di kepala dan belakang yang menunjukkan bahwa itu bukan albino. axolotl putih dengan mata hitam tidak albino. Sementara d / d mencegah sel-sel pigmen axolotl ini dari migrasi dari atas binatang, ini tidak berarti bahwa semua leucistics akan memiliki sel-sel warna pada kepala dan punggung - melihat mata menjadi penemtu.
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WHITE LION GENETICSWhite lions are not albino (unpigmented) but are leucistic - leucism describes an effect rather than a particular gene. They have pigmentation which is visible in the eyes, paw pads and lips. Their eyes are usually the normal hazel or golden colour although some have blue, blue-green or greyish-green eyes. At birth, the cubs are snowy white and may be described as resembling polar bear cubs. The birth colour gradually darkens to a pale cream colour known as blond (another name for white lions is blond lions). The mane and tail tuft remain a paler shade. singa putih tidak albino (tidak berpigmen) tetapi leucistic/leucistik - leucism menggambarkan efek daripada gen tertentu. Mereka memiliki pigmentasi yang terlihat di mata, bantalan kaki dan bibir. Mata mereka biasanya cokelat normal atau warna emas meskipun beberapa memiliki biru, mata biru-hijau atau hujau-keabu. Saat lahir, anaknya yang bersalju putih dan dapat digambarkan sebagai menyerupai anak beruang kutub. Warna lahir secara bertahap menggelap menjadi warna cream pucat dikenal sebagai pirang (nama lain untuk singa putih singa pirang). Surai dan ekor seberkas tetap berwarna pucat.
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Leucism is a complete or partial lack of melanin in the feathers, but not necessarily the soft tissues. It is sometimes referred to as ‘partial albanism’ but if you’re familiar with the definition of albanism (which hopefully you are now!) you know the term ‘partial albinism’ is oxymoronic. Leusistic birds can have one or multiple white feathers, as is the case with my friend in Bellevue, or be completely white but with regularly colored eyes. Their feet and bills may or may not appear pink like that of an albino bird’s. Leucism/leucistic/leucistik adalah kurangnya lengkap atau sebagian dari melanin dalam bulu, tetapi belum tentu di jaringan lunak. Hal ini kadang-kadang disebut sebagai 'albanism parsial' tetapi jika Anda terbiasa dengan definisi albanism , Anda tahu istilah 'albinisme parsial' adalah oxymoronic. burung Leusistic dapat memiliki satu atau beberapa bulu putih, seperti halnya dengan teman saya di Bellevue, atau benar-benar putih tapi dengan mata berwarna teratur. kaki dan bills mereka mungkin atau tidak mungkin muncul merah muda seperti pada burung albino ..
...............................
Leucism kerap
disalahpahami sebagai albinism. Contohnya, ada katak yang memiliki jenis pigmen
xanthophores (jenis pigmen selain melanin), maka warnanya tidak putih polos,
melainkan kuning pucat.
Last but not
least, hewan al;bino di muka bumi tergolong sangat langka. Sebuah studi di
universitas Wisconsin, memperkirakan mutasi albino muncul satu dalam setiap
42.500 kelahiran!
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Leucism sering
keliru dengan albino, padahal keduanya adalah kondisi yang
berbeda. Kedua kondisi ini tidak dikategorikan "tidak normal"
karena perbedaan tersebut adalah bukti keragaman hayati. Tidak ada istilah
normal atau tidak, yang ada hanya keragaman hayati.
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3. Leucism
Leucism adalah salah satu
peristiwa / kasus yang menyebabkan timbulnya warna pada Love Bird pied (
Blorok) . Leucism merupakan peristiwa rusak atau hilangnya melanoblast yang di
bentuk di Puncak syaraf sehingga berakibat melanosit hampir sepenuhnya tidak
ada pada bulu . Ketika melanosit absen di bagian bulu maka tidaklah mungkin
pigmen disetorkan di daerah tersebut. Jadi Leucism bukan di sebabkan oleh
kesalahan aktivitas pada enzim tyrosinase atau deposit eumelanin hitam.
..........................
Why is this humpback all white? Willow has a condition called leucism, which causes a reduction in all skin pigments. How is leucism different from albinism you may ask? Albinism only effects the production of melanin, while leucism prevents formation of all pigments. disebut leucism/leucistic/leucistik , yang menyebabkan pengurangan semua pigmen kulit. Bagaimana leucism berbeda dari albinisme Anda mungkin bertanya? Albinisme hanya efek produksi melanin, sementara leucism mencegah pembentukan semua pigmen.
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What is Leucism?
It is similar and often confused with Albinism, but the difference between the two is that in Albinism there is a defect in the production and distribution of melanin (affects entire animal); while in Leucism there is only a reduction in skin, hair or feather pigment in the process of development (normally only affects patches of the animal).
One key difference is that when an animal is Albino it has red eyes, while with Leucism it doesn't
Apa leucism/leucistic/leucistik ? Hal ini mirip dan sering membingungkan dengan Albinisme, tetapi perbedaan antara keduanya adalah bahwa di Albinisme ada cacat dalam produksi dan distribusi melanin (mempengaruhi seluruh hewan); sementara di leucism hanya ada pengurangan di kulit, rambut atau pigmen bulu dalam proses pembangunan (biasanya hanya mempengaruhi patch dari hewan). Salah satu perbedaan utama adalah bahwa ketika hewan adalah albino akan memiliki mata merah, sementara dengan leucism itu tidak
It is similar and often confused with Albinism, but the difference between the two is that in Albinism there is a defect in the production and distribution of melanin (affects entire animal); while in Leucism there is only a reduction in skin, hair or feather pigment in the process of development (normally only affects patches of the animal).
One key difference is that when an animal is Albino it has red eyes, while with Leucism it doesn't
Apa leucism/leucistic/leucistik ? Hal ini mirip dan sering membingungkan dengan Albinisme, tetapi perbedaan antara keduanya adalah bahwa di Albinisme ada cacat dalam produksi dan distribusi melanin (mempengaruhi seluruh hewan); sementara di leucism hanya ada pengurangan di kulit, rambut atau pigmen bulu dalam proses pembangunan (biasanya hanya mempengaruhi patch dari hewan). Salah satu perbedaan utama adalah bahwa ketika hewan adalah albino akan memiliki mata merah, sementara dengan leucism itu tidak
What is the Endosymbiotic theory of an Leucistic Alliagtor? All of the Leucistic Alligator's cells have evolved from Prokaryotes (cells with no nucleus) to Eukaryotes (cells with nucleus') and then specifically from there to Aerobic Eukaryotes (ones that require oxygen). Apa teori endosimbiotik dari Leucistic Alliagtor?
Semua sel-sel Leucistic/leucistik/leucism
Alligator ini telah berevolusi dari
Prokariota (sel tanpa inti) ke Eukariota (sel dengan nukleus ') dan kemudian
secara khusus dari sana ke Aerobic Eukariota (yang membutuhkan oksigen).
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Melanin is the main pigment found in mammals. It
is responsible for the color of hair and fur. There are different types of melanin (eumelanin and
pheomelanin), and they produce a huge color range, from black to sandy to red.
Melanin adalah pigmen utama yang ditemukan pada mamalia. Hal ini bertanggung jawab untuk warna rambut dan bulu. Ada berbagai jenis melanin (eumelanin dan pheomelanin), dan mereka memproduksi berbagai warna besar, dari hitam ke berpasir merah.
Melanin adalah pigmen utama yang ditemukan pada mamalia. Hal ini bertanggung jawab untuk warna rambut dan bulu. Ada berbagai jenis melanin (eumelanin dan pheomelanin), dan mereka memproduksi berbagai warna besar, dari hitam ke berpasir merah.
. Leucism is sometimes mistaken for albinism, but leucism is a condition characterized by reduced pigmentation in animals. It affects all pigments, not just melanin, and animals with leucism have normal eye color, while animals with albinism tend to have red eyes. Leucism/leucistic/leucistik kadang-kadang keliru untuk albinisme, tetapi leucism adalah suatu kondisi yang ditandai oleh berkurangnya pigmentasi pada hewan. Ini mempengaruhi semua pigmen, bukan hanya melanin, dan hewan dengan leucism memiliki warna mata normal, sedangkan hewan dengan albinisme cenderung memiliki mata merah.
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Variasi Sugar Glider
1. Classic
Grey/Standard Grey
1. Classic
Grey/Standard Grey
Merupakan warna sugar glider yang paling
umum dijumpai, dimana tubuh bagian atas mereka berwarna abu-abu dengan garis
hitam yang membentang dari ujung kepala hingga ekornya. Mereka juga memiliki
garis berwarna gelap yang membentang dari telinga hingga ke mata mereka. Sugar
Glider jenis ini merupakan gen dari Sugar Glider yang paling dominan. Turunan
dari Clasic Grey/Standard Grey ini adalah
a. Black
Beauty
Jenis ini biasanya memiliki garis yang
sangat hitam, terkadang memiliki lingkaran hitam di sekitar mata yang disebut
"eye liner". Mereka juga memiliki buku-buku jari berwarna hitam,
garis hitam dari telinga ke mata. Jenis ini memiliki garis berwarna hitam di
dagu yang nampak seperti tali dan memiliki warna bulu yang gelap dibagian
perut.
b. Lion
Tubuhnya berwarna kuning keemasan dengan
bentuk hidung yang lebih pendek dan wajah yang lebih bulat.
c. Cinamon
Memiliki tubuh berwarna kecoklatan
seperti kayu manis dengan garis berwarna coklat kemerahan yang gelap. Banyak
yang menganggap bahwa warna ini muncul akibat dari diet yang buruk.
Albino
Sugar Glider dengan seluruh tubuh yang berwarna putih
dengan mata berwarna merah. Jenis ini umumnya lahir dengan pigmentasi yang
minim berwarna kuning berlian. Mereka memiliki garis yang samar di bagian ekor
atau sepanjang patagium dan tangan. Albino merupakan gen resesif, sehingga
harus dipasangkan dengan glider lain dengan gen resesif yang sama agar dapat
mereproduksi seekor Sugar Glider albino.
Leucistic
Memiliki bulu
berwarna putih yang solid tanpa garis di tubuh dan di telinganya. Leucitic
memiliki mata berwarna hitam. Sugar Glider jenis ini merupakan Sugar Glider
dengan gen resesif sehingga harus dipasangkan dengan Sugar Glider lain dengan
gen resesif yang sama agar dapat mereproduksi leucistic.
White
Face
Jenis ini memiliki bulu berwarna keemasan yang ringan tanpa
garis memanjang dibawah telinga kearah dagunya. Jenis ini memiliki gen
dominan dan hanya membutuhkan 1 kali reproduksi dari pasangan yang memiliki gen
ini untuk menghasilkan keturunan yang berwajah putih.
White Tip
Sugar Glider dengan warna abu-abu standar dengan bulu
berwarna putih diujung ekornya
Creamino
Bulunya berwarna krem kecoklatan dengan garis yang juga
berwarna kecoklatan dan mata berwarna merah delima.
Platinum
Bulunya berwarna keperakan dengan garis berwarna light grey
yang lebih kecil dibandingkan garis yang terdapat pada Sugar Glider jenis lain.
Kukunya berwarna putih yang dapat memanjang hingga ke pergelangan kakinya.
Melanistic
Jenis Sugar Glider yang banyak memiliki pigmen gelap dengan
konsentrasi melanin yang sangat tinggi. (Kebalikan dari Jenis Albino)
Caramel
Jenis ini dianggap subspecies yang berbeda. Sebenarnya
jenis ini berwarna grey standard yang cenderung berwarna seperti sampange dari
pada warna karamel dengan kaki dan tangan yang
cenderung berwarna putih.
10. Double
Recessive
Merupakan Sugar Glider dengan kombinasi
2 warna resesif yang menghasilkan Sugar Glider dengan bulu berwarna putih yang
solid dan mata berwarna merah. Sedikit sulit untuk mengidentifikasikan SG jenis
ini saat baru lahir karena warna pada telinganya baru akan muncul 2 minggu
setelah lahir hingga masa OOP. Jenis ini dihasilkan dari kombinasi :
a. Creamino
x Leucistic
b. Creamino
x Platinum
c. Albino
x Leucistic
d. Albino
x Platinum à Kombinasi ini memerlukan gen
leucistic.
e. Creamino
x Albino
11. Mosaic
Bulunya akan memiliki berbagai pola dan
warna yang acak. Sugar Glider ini memiliki tangan dan kaki yang berwarna putih
(atau hanya kakinya saja) dan kumis berwana putih dan hitam. Jenis ini memiliki
gen yang dominan dan hanya membutuhkan waktu 1 kali reproduksi dari pasangan
Sugar Glider untuk memiliki gen yang dapat mereproduksi keturunan mosaik.
Variasi dari Mosaic ini adalah :
a. Piebald
(Belang)
b. Jenis
ini memiliki pola bercak yang berwarna hitam pada area yang tak berpigmen yang
umumnya berwarna putih. Pola warnanya tidak teratur dan asimetris. Beberapa SG
ada yang menunjukkan warna mata yang sesuai dengan bercak pada tubuhnya.
c. b. Ring
Tail
Jenis ini memiliki cicin pada ekornya yang dapat terdiri
dari 1 cincin atau lebih dengan variasi warna mulai dari putih, abu-abu muda
hingga hitam.
c. Silver Mosaic
Jenis ini memiliki warna bulu keperakan dan biasa disebut juga
Platinum Mosaic Color, namun sebenarnya jenis ini tidak memiliki gen Platinum.
d. White Mosaic
Jenis ini memiliki warna bulu berwarna putih yang nampak seperti
SG Leucistic namun memiliki bintik berwarna gelap pada telinga. Joey jenis ini
sejak lahir secara keseluruhan sudah berwarna putih.
e. True Platinum Mosaic
Memiliki karakteristik sebagai SG Mosaic dengan leher yang
berwarna putih dan cicin pada ekornya, namun secara genetik, SG ini adalah
termasuk dalam SG Platinum
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Jenis Jenis Sugar Glider
Sugar Glider (SG) Mosaic, hasil dari
kawin silang dari Sugar Glider Grey dengan Sugar Glider Leucistic. Hasil dari Breedingan
(kawin) ini tidak selalu bagus, ada juga corak yang hanya sedikit saja, bahkan
ada yang hanya kelihatan garis tengah saja. Sugar Glider bisa dibilang jenis
Mosaic dikarenakan adanya kelainan GEN yang di hasilkan dari Sperma sih jantan,
bisa dibilang sih jantan mempunyai jenis Leucistic, dan sebaliknya sih betina
jenis Grey..
jangan terlalu memaksakan mereka untuk
breeding, dikarenakan jika mereka tidak breeding, itu pertanda mereka merasa
tidak cocok, dan akan menyebabkan kematian pada sih betina jika terlalu dipaksa
untuk breed. Di karenakan mereka berbeda GEN memang sangat lucu jika mempunyai
Sugar Glider jenis ini. tetapi sangat susah untuk menciptakan jenis ini,,
Sugar Glider WhiteFace
(WF), hasil kawin silang yang sama dari Leucistic, hasil dari mereka juga hampir sama..
Lalu apa yang membuat mereka berbeda? Yaa jika diperhatikan hanya dibagian muka
saja yang berwarna putih.. maka dari itu di sebut WhieFace, tidak tau kenapa
hanya mukanya saja yang berubah,, menjadi putih, tapi untuk kalian jangan
takut, gagal yah dikarenakan semua SG yang sudah kawin silang sudah dipastikan
diatas pasaran harga SG pada umumnya.
Sugar Glider Ring Tail
(Ekor Cincin) Hasil kawin silang yang sering terjadi jika SG betina Leucistic
dan SG jantan Grey, Ring Tail sudah jelas dalam bahasa indonesia Ekor Cincin..
SG jenis ini mempunyai Ekor yang belang - belang dan berwarna abu - abu putih.
Jenis ini sangat jarang ditemukan, dan jika ada pemilik yang mempunyai jenis
ini pasti mereka tidak akan menjualnya. Dikarenakan sangat sulit untuk
menjadikan jenis Ring Tail ini.
Sugar Glider Creamino,dan
Albino Sugar Glider Creamino ini mempunyai warna Cream, sangat sulit untuk
menemukan SG ini dikalangan SugarGliderLovers. Jika ada yang mempunyai jenis
ini pasti karaternya galak. SG jenis ini memang susah untuk di handle, tetapi
jenis ini mempunyai harga yang tinggi, dikarenakan jenis ini jarang ditemukan
dihutan.
Dan Sugar Glider Albino
sudah dipastikan berwana putih dan mempunyai bola mata berwarna Merah.. Jenis
ini memang susah di temukan, jika ada yang mempunyai jenis Albino pasti mereka
tidak akan menjualnya walaupun karakternya tidak bisa dihandle. Kenapa mereka
tidak ingin menjual Sugar Glider tersebut? bagi kami pecinta Sugar Glider pasti
bilang untuk aset berkembang biaknya jenis Mosaic.. Ya, Benar!! jenis Leucistic
adalah keturunan Albino dan Cremino.. Sugar Glider Grey bisa mempunyai
kerturunan yang berbeda jenis dengan induknya yang grey, dikarenakan kelainan
GEN yang kami buat main untuk menciptakan jenis Mosaic.
Cara merawat Sugar Glider
tidak begitu rumit, jika kamu yang suka berpergian, bawalah Travel Pouch untuk
tempat mereka. mungkin kalian akan bertanya apa itu travel pouch. Travel pouch
adalah tas untuk tidur SG, tas tersebut dipakai jika kita akan berpergian, dan
membawa SG. Travel pouch berbahan lembut, dan pastinya ada ventilasi udara
untuk SG bernafas. Jadi kalian jangan takut SG kesayangan kalian mati, karena
mereka akan tertidur pulas di dalam Travel pouch pada saat anda berpergian,
tetapi jangan sekali sekali memasukan SG ke Travel pouch pada saat malam hari.
Dikarenakan SG adalah Mamalia yang aktif pada malam hari, SG akan beraktifitas
dimalam hari untuk mencari serangga dan bermain dengan sejenisnya.
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WHY
WHITE’S NOT SO WHITE, AFTER ALL: THE STORY OF LEUCISM
5 years ago
6
·
When I was a kid, visiting the St. Louis Zoo was one of my favorite weekend activities. My most beloved attractions
included feeding leaves to giraffes(what huge tongues!), spotting tiny frolicking marmosets in the open-atrium forest
inside the primate house, and watching the silly ways in which bears slumber
during the hot, humid afternoons of the Missouri summer. Then, one year, the
Zoo announced something I found new and exciting — and more than a little bit
baffling.
·
White alligators. With blue eyes.
·
For weeks, I begged my parents to take me.
Finally, they succumbed and we made our visit to the Zoo’s herpetarium. The facility housed a
number of intriguing residents, like twenty-foot-long pythons and 200-pound
tortoises, but they were no match for the white alligator. To me, the bizarre
creature was nothing short of a conundrum of nature. You see, back then I
knew, having raised many generations of gerbils of various colors, that
albinistic animals don’t have blue eyes. In
most albinistic vertebrates, the production of melanin is so lacking, that the
eyes appear pink, reflecting the coloring of red blood cells in the
capillaries. This blue-eyed alligator I needed to see for myself to verify
these wild claims of iris pigment on a white animal.
·
As usually happens with the animals we most want to see at the
zoo, the white alligator was less than compliant with my curiosity. Her head
was tucked beneath a log in her habitat, leaving only her milky skin for my
juvenile inspection. The information placard next to her display, however, held
the next piece of the puzzle: she was born with a recessive gene giving rise to
her low pigment condition called, also called leucism.
·
In the years that followed my encounter with the white
alligator, I became fascinated by all kinds of other animals. In fact, I
quite nearly forgot about that blue-eyed crocodylian. That is, until I heard a
story about the rare, endangered white lions of Africa. By this time, the Internet had conveniently
entered my vocabulary, so I booted up our Packard Bell computer, logged onto
AOL 2.0 via our only home phone line, and searched for more information on
these ghostly felines.
·
Again, leucism was
responsible.
So, it appeared that more animals were affected by this condition than reptiles
alone. Armed with the power of the Internet, I kept digging. I found peacocks
displaying white sunbursts of feathers and pythons with creamy diamond patterns
weaving down their bodies. I discovered lightly guilded bison and tuxedo
penguins with tan coattails. Indeed, I found an entire world of pale-colored
animals, residing somewhere between their pigmented counterparts and albinos.
·
Unlike in most cases of albinism, leucistic animals generally retain some essence of
their normal pigmentation. Thus, while the leucistic python may appear “white,”
the normal diamond patterning persists in various creamy shades. And the irises
of blue eyes, like the white alligator’s, contain pigments — just in very low
quantities.
·
Recently, a series of beautiful photos of a white hummingbird
were released on various internet news venues. You can find them here. So, take a look — which
genetic condition does this bird have, albinism or leucism?
·
Right. Albinism! This pale little hummingbird, captured in
photographs feeding against a brilliant display of colored flowers, entirely
lacks the ability to manufacture feather and iris pigment. Barely the size of
an adult human’s thumb, the miniscule ruby-throated hummingbird
normally flaunts an emerald back and wing coat and a brilliant red throat
coat. But not our little albino celebrity.
·
At last, the moral of our story is that first impressions may be
deceptive. An alligator with leucism may appear“white” — but compared with the albino
hummingbird in recent press, the white alligator is actually not all that
white, after all.
·
Want to witness some white animals on your own? The California Academy of
Sciences has just the albino alligator for your fancy! His name is Claude. If he isn’t enough, the San
Francisco Zoo has American white pelicans and Chilean flamingos (whose feathers would
be much less pink if it weren’t for their diet!). Or just head outside and keep
an eye out for a pair of cooing white morning doves.
·
Lastly, meet the largest white animal on Earth! This is Migaloo, a white humpback whale
residing in the waters off eastern Australia.
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Genetics and Colour
Overview
The Axolotl is studied the
world over for several reasons. All of the traits which make it so suitable for
study, as for all living things, are dependent upon its genes. This page will
attempt to give a brief overview of axolotl genetics, mainly from the viewpoint
of the hobbyist, who tends to be most interested in colour.
Axolotls have 28
chromosomes per cell, in fourteen pairs. Humans have 46 chromosomes in 23
pairs. A chromosome is a thread-like structure composed of DNA and protein. The
length of a chromosome is made up of many units of DNA called genes. Each gene
has a special place on a chromosome and the position which it occupies is called
the locus of that gene.
When an axolotl
reproduces, the sperm from the male (which contains 14 chromosomes) and the egg
from the female (which also contains 14 chromosomes) fuse to form the zygote,
the first cell of the new axolotl. So each new cell of this new animal has 28
chromosomes. However, in the production of gametes (the sperm and egg cells)
via the process known as meiosis, small exchanges of parts of the chromosomes
take place (known as "crossing-over"), as well as a random allotment of
chromosomes from the mother or father's own parents to each gamete (which means
a gamete could have 2 maternal chromosomes and 12 paternal, or any other
combination).
So when axolotls
reproduce, each new larva is a genetically distinct individual, different from
its siblings and its parents. This is the essence of genetic variation. An
animal's genotype is what its genes "say" it is, and its phenotype is
the result of the gene, its expression. Mutant animals are those with genes
differing from what is accepted as normal.
Colour
The colour of axolotls is
dependent upon pigment cells called chromatophores. These cells are
melanophores (containing eumelanin, a black-brown pigment), xanthophores
(containing carotenoids and pteridines, yellow and reddish pigments) and iridophores
(containing crystalised purines, which impart a shiny iridescence).
Each cell in an axolotl,
as stated above, contains 14 pairs of chromosomes. Every characteristic of the
animals is coded for by genes on pairs of chromosomes. The genes for the pigment
cells are inherited independently of one another, and there is no known linkage
to any other genes. So, each pigment type is coded for by two different genes,
one on each of a pair of chromosomes. These contrasting genes that code for the
same characteristic are known as alleles. A pair of alleles is written like
this: X/x. A capital letter means that gene is a dominant gene, as opposed to
the small letter, which means that gene is recessive.
For example, the allele
that controls albinism could be found in an axolotl in one of the following
combinations: A/a, A/A, or a/a. If the animal was A/a, because a is recessive
and A is dominant, the animal's phenotype wouldn't be albino, but it would
still carry the gene for albinism (since it has an "a"). Since it
carries both "A" and "a", it is known as
"heterozygous". If the animal had the A/A combination, its phenotype
wouldn't be albino, and it wouldn't carry the gene for albinism (both genes
being the same, it is called "homozygous" for "A"). If it
were homozygous for "a" (i.e. a/a), the animal's phenotype would be
albino. Since "a" is recessive, both alleles need to be "a"
in order for albinism to be expressed in the phenotype. Albinism results in a
lack of eumelanin (the dark pigment). In axolotls, it also results in an
increased number of xanthophores (yellow pigment cells).
In the same way that a/a
results in a lack of eumelanin, m/m (melanoid) results in a lack of
iridophores. Such animals are very dark, with no reflective pigment cells at
all. M/m or M/M would result in normal iridophore development. Animals
homozygous for "ax" (i.e. ax/ax) are axanthic, meaning they have no
visible xanthophores or iridophores. Such animals are almost as dark as
melanoids. Animals homozygous for both the albino gene and the axanthic gene
appear to be slightly off-white (yellowish). The following table summarises the
colour genes.
You may have noticed the
"d" gene. This gene is a developmental mutant and not a pigment
mutant like the others. Animals homozygous or heterozygous for "D"
produce large numbers of yellow xanthophores. In combination with melanophores,
we get the wild type colouration (dark brown/olive-green). However, in animals
homozygous for "d", the normal pigment cells are produced, but they
never migrate off the neural crest of the embryonic animal, resulting in the
white phenotype. It is important to realise the this animal is not albino. This
phenotype is white, but has dark eyes. It is known as leucistic. Simple
albinism in axolotls leads to a yellow/golden animal, with red/pink eyes. In
order to produce a white albino, the animal must have the d/d genotype in
combination with the a/a genotype. Melanoid albinos (m/m with a/a) are also
white animals with pink/red eyes. This can make initial identification of a
white albino's phenotype difficult to determine for the novice.
Colour types
Here are photos and
descriptions of some of the commonly available colour variants and an
explanation of the genetics behind them.
Wild Type
Wild types vary somewhat in
exact colour, but are generally a shade of dark brown with black, yellowish,
and shiny patches/speckles. The phenotype of wild type animals is dark,
non-melanoid, non-albino and non-axanthic. In the photo below, the animal on
the right is a wild type female. This is the typical wild type appearance. You
may also encounter tan or very lightly speckled variants. Wild types are not
homozygous for any of the colour mutations.
Melanoid
In the above photo, the
animal on the left is a female melanoid. As described earlier, melanoids lack
the "shiny" pigments (crystalised purines). The amount of yellow
present is also much reduced. In contrast, the number of melanophores (dark
pigment cells) is greatly increased, resulting in a black animal. The easiest
way to determine if an animal is melanoid or a dark wild type is to look at the
eyes: non-melanoids have a shiny ring around the pupil of the eye, while
melanoids (and melanoid albinos) do not. Melanoids are homozygous for
"m" only (i.e. m/m), but they may be heterozygous for other colour
mutations.
White (also called Leucistic)
Commonly known as leucistic, the phenotype is d/d, non-melanoid, non-albino and non-axanthic. Here's a picture of a large adult female. Notice the black eyes and small number of melanophores on the head and back which indicate that it is not an albino. White axolotls with black eyes are not albino. While d/d prevents the axolotl's pigment cells from migrating off the top of the animal, this does not necessarily mean that all leucistics will possess colour cells on the the head and back - look at the eyes to be certain. Putih (juga disebut Leucistic)
Umumnya dikenal sebagai leucistic/leucistik/leucism , fenotipe adalah d / d, non-melanoid, non-albino dan non-Axanthic. Berikut adalah gambar dari betina dewasa besar. Perhatikan mata hitam dan sejumlah kecil melanophores di kepala dan belakang yang menunjukkan bahwa itu bukan albino. axolotl putih dengan mata hitam tidak albino. Sementara d / d mencegah sel-sel pigmen axolotl ini dari migrasi dari atas binatang, ini tidak berarti bahwa semua leucistics akan memiliki sel-sel warna pada kepala dan punggung - melihat mata menjadi penemtu.
Albino
Phenotype is albino a/a
(lacking melanophores). There are many kinds of phenotypically-different albino
axolotl. Here are some of them. The first is the golden albino (D/D a/a or D/d a/a). It has normal migration of
pigment cells, but lacks melanophores, hence the yellow/gold appearance.
The second kind of
albino I will mention is the axanthic albino. It has normal pigment cell
migration but is homozygous for the albino gene and the axanthic gene (a/a and
ax/ax), meaning it lacks melanophores, xanthophores and iridophores. It is
almost white, but becomes yellow with age due to the accumulation of
riboflavins from its diet. Here's a picture of one of the former Indiana
University Axolotl Colony's albino axanthic specimens
The third kind of
albino is the white albino. It is homozygous for "d" and
"a" (d/d and a/a). The photo below is one of the former Indiana University
Axolotl Colony's white albinos. Note the presence of iridophores (shiny pigment
cells) in its gill branches.
The fourth kind of
albino that I will discuss is the melanoid albino. It is homozygous for
"m" and "a" (m/m a/a). This is a male axolotl. While a
non-albino melanoid would be black, the combination of melanism and albinism
"removes" all pigment except a tiny hint of yellow xanthophores on
the head and back.
Conclusion
Axolotls come in many
different colour variations. Axolotl breeders often produce an odd offspring
whose phenotype defies what the breeder knows to be its genotype. Piebald
axolotls (not
just on the top of the body like a leucistic), yellow leucistics with black
spots, and the harlequin (orange and black patches on a white axolotl) are just
a few examples of what chance can present. You can see the huge variety of
axolotl colour variations in Caudata.org's User Photo
Gallery.
Keep your eyes open for
unusually coloured axolotls that don't match the descriptions here. They might
be very special indeed.
........................
Incredibly Basic Axolotl Genetics
Genetics are confusing. So I will explain what I understand, but
even that is somewhat limited.
Phenotype: what they physically look like
Genotype: Their genetic makeup “code”
Heterozygous: Different genetic codes eg: D/d
Homozygous: Same genetic codes eg: d/d
A wildtype is dominant D (dark), and will always be heterozygous
= D/d
A leucistic is recessive to wildtype but dominant to albino.
It will always be homozygous = d/d
An albino is recessive, and homozygous = a/a
A golden albino is always either D/D a/a or D/d a/a. The albino
gene is always recessive homozygous a/a, and the dark pigments which help make
the axolotl gold are written as D/D or D/d.
An axolotl's parentage is very important in breeding. If they
come from different parents, it can greatly affect the outcome of their
offspring. A leucistic, although d/d, may have an albino parent, so is
recessive for albino, and with the right pair up, can create albino babies,
despite not being an albino itself. Another axolotl who was albino, or
recessive for albinism would be needed.
Dominant genes, such as the dark pigment in wildtypes and golds,
need only one to show up in offspring, whereas recessive genes, such as leucism
and albinism need one from each parent to show up.
The dark gene will generally counter leucism, and albinism (turns out golds
instead of whites), but it depends on the two genotypes being combined, and
punnet squares are (somewhat) useful for this, on the most basic level.
................................
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WHITE LIONS - MYTHOLOGY, HISTORY & GENETICS
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I am grateful to Paul McCarthy and others for researching, providing and correcting extensive material, genealogies, historical and current information about white lions. Thanks are also due to Kevin Chambers of the Zoological Animal Reproduction Center for further information on white lions. More detailed information on the history and ecology of white lions may be found in Linda Tucker's book "Mystery of the White Lions - Children of the Sun God
White Lions 2: White Lions in Captivity Today
The White Lion in Mythology and Nature
Accounts of white lions have been around for centuries in Africa, but have often been dismissed as superstition. It has been part of African folklore since prehistoric times and according to legend white lions were children of the Sun God, sent to earth as gifts.
Oral traditions recalls the appearance of white lions over 400 years ago during the reign of Queen Numbi in the region now known as Timbavati. A shining star was seen to fall to the ground, but when Queen Numbi and her people approached, they found it to be a shining ball of metal, brighter than the sun. Queen Numbi, who was an elderly and infirm woman, was swallowed by its light and received by strange beings. When she emerged again, she had been restored to health and youth. The fallen star remained there for some days and then rose back into the sky. Animals with strange deformities were born in that region - cattle with 2 heads, white impala and green-eyed white leopards and lions. To this day, white animals are born in Timbavati, including a blue-eyed albino elephant that was shot by white hunters. Whether or not you believe in visiting spaceships, it is now known that radiation can cause mutations such as those described.
White lions were central to an April Fool's joke in 1860. Late in March of that year, numerous people throughout London received a plausible looking invitation saying "Tower of London - Admit Bearer and Friend to view annual ceremony of Washing the White Lions on Sunday, April 1, 1860. Admittance only at White Gate. It is particularly requested that no gratuities be given to wardens or attendants." By twelve noon on April 1, a large crowd had gathered outside the Tower of London in accordance with the invitation. Lions hadn't been kept in the tower for centuries; the Royal Menagerie having outgrown the tower and become the Royal Zoological Society's "Gardens" in Regent's Park). There were no captive white lions until late in the 20th century. On realising the joke, the disappointed crowd eventually dispersed.
An alternative explanation is that the recessive gene for white/blonde is part of the lion's genetic heritage from the days when lions roamed far more widely. Their habitats included snowy and desert regions where blonde and white colours give better camouflage than tawny and the more successful pale colour morph would come to predominate in such places.
While accounts of white lions have been around for centuries, they were dismissed as superstition. There are now around 300 white lions in captivity and they have been returned to the wild. However, like white tigers, they are an attractive man-perpetuated mutant strain rather than an endangered species in their own right.
The Timbavati White Lions
The first authenticated sightings were in 1928. The first White Lion sighting by a European was in the Peru area of Timbavati in the early 1940s by Joyce Mostert, whose family owned large tracks of land in the area. During March 1959, twelve lions with 2 white cubs were seen near Tshokwane in the Kruger Park; though unfortunately they were never seen again. David Alderton's "Wild Cats Of The World" claimed there were albino lion cubs in Kruger in 1960, but they were more likely to have been white lions. In 1974, a light grey lion cub was born at Birmingham Zoo, Alabama, but was darker than the Timbavati white lions reported a year later.
No truly white lions were captured until 1975 when a litter containing 2 white cubs was found at Timbavati Game Reserve, adjacent to Kruger National Park. The white cubs were discovered by researcher Chris McBride. Their story is documented in the book "The White Lions of Timbavati". The 2 cubs were a male and a female that they named Temba (Zulu for "hope") and Tombi ("girl"). Their tawny brother was called Vela ('surprise') and sired a litter before being sold by Pretoria. Mcbride realised that the white cubs were disadvantaged in the wild - they were highly visible to both prey and to predators. Temba, being a male, would eventually be ejected from the pride and become nomadic until he managed to take over another pride. As a nomad, the highly visible Temba would have little chance of catching prey and would most likely starve. Tombi was safer, since lionesses remain with the pride, but would be at risk if she was ejected for any reason. More than once, the white cubs were found in an emaciated condition and the researchers found it necessary to provide kills for them..
In 1976 a white female cub was born among a large litter north-west of Tshokwane; at about 2 years old her colour darkened considerably. In 1977, an aerial census of the Central District observed a white male lion approximate 2 years old and yellow-white rather than pure white. By the age of 4, this lion (which had formed an alliance with 2 other adult males) was also darker, but its tail tip remained buff rather than becoming black. In August 1976, a white female cub was sighted in another subgroup of the pride and belonging to a different lioness. She was named Phuma (meaning "to be out of the ordinary"). She was part of a large litter that displayed a gradation of colour ranging from pure white, through pale blond to normal tawny. At the age of about 2 years, this female left the Timbavati reserve and was unfortunately killed. Her skin was later found for sale in a shop in the town of Sabi. This prompted concerns that Temba and Tombi would meet the same fate. As a result, McBride decided to capture Temba, Tombi and Vela (although tawny, Vela carried the gene for white). The cubs were taken to the National Zoo in Pretoria, South Africa where Temba produced several cubs before his death in 1996. In 1981, The white female produced a pure white cub which unfortunately died shortly after birth. Vela was sold and went to an unknown destination. It is not known whether Vela left any descendants, though the white lions in the Ouwehands Dierenpark (Netherlands) and a private South African Zoo appear to be from the Temba a Vela lines. Since the removal of Temba, Tombi and Vela, only a few white or pale cubs were born from time to time. One female lived for several years and was often seen hunting with her pride; she was killed in a territorial fight in 1993 and no white lions have survived since then.
Pretoria Line - White Lions of Timbavati Genealogy (large image, opens in new window)
Many people believe the cubs should have been left to take their chances in the wild. The genes to produce white in lions are now believed lost in the general population. White lions were never seen anywhere other than Timbavati Game Reserve and the white gene pool was almost definitely limited to this area. Lions in Timbavati have been killed by poachers. Several lions survived from the original white lions of Timbavati and are descended from Temba. A heterozygous tawny lion at Pretoria carries the gene for white and could pass this on to his offspring. Two heterozygous tawny males were kept at Cincinnati Zoo and are now at a private reserve in Africa. A white female and a heterozygous tawny male are at the Zoological Animal Reproduction Center in Indiana, USA. A second female from the original strain was unfortunately she was killed by the other female while on loan to a zoo.
Kruger and Umfolozi White Lions
There is more than one genetic strain of white lion. In 1977, Johannesburg Zoo caught a heterozygous male apparently from a different pride to that studied by Chris McBride. This wild tawny male came from litter that contained a white lion. Johannesburg Zoo claims to be the first in the world to have bred white lions in captivity. Timba, a brown lion from the Timbavati game reserve, was shot and was taken to the zoo for medical treatment. He was believed to have the rare white gene and was bred to a captive female and later mated to one of his own daughters. His white daughter Bella was born in 1982 (along with tawny littermate Danie) and she went on to produce many other white lion cubs. The lion that founded the Pretoria Zoo bloodline was known to have a white sibling in the wild and was therefore a carrier of the white gene. When mated with his own daughters, white offspring were produced. This bloodline is represented at zoos in Philadelphia, Toronto, China, Germany and Japan. In 1979, three different litters containing white lions were recorded in the huge Kruger National Park. In March 1979 a female lion with 3 white cubs was observed neat Tshokwane. In September 1979 another 3 white cubs (from 2 different lionesses) was seen. In 1979, the most recent litter of white cubs, all female, in the Kruger National Park were seen to have sarcoptic mange and were captured for treatment. In 1979, a white lion was observed in the Umfolozi Game Reserve in Zululand.
Johannesburg Line of White Lions (large image, opens in new window)
In 2010, two white lion cubs were reported in Ingwelala, adjacent to the Kruger National Park. They were born to a tawny lioness, demonstrating the gene still survives in the wild. Unfortunately both cubs disappeared.
The Sanbona White Lions
Conservationist Dr Gaston Savoi, Co-Chairman of Mantis Collection, aims to return the white lion to the wild (although they are really a mutant strain perpetuated in captivity by humans, just like white tigers). In 2003, white lion "Jabulani" and white lioness "Queen" were purchased and released into Sanbona Wildlife Reserve, South Africa. In May 2004, this pair produced 3 cubs (2 males, 1 female). In June 2004, a white lioness and her 3 five month old cubs joined them at Sanbona. The Global White Lion Protection Trust saved these animals from a life in captivity. These lions have made their own kills in addtion to receiving carcasses of zebra and kudu.
WHITE LION GENETICS
White lions are not albino (unpigmented) but are leucistic - leucism describes an effect rather than a particular gene. They have pigmentation which is visible in the eyes, paw pads and lips. Their eyes are usually the normal hazel or golden colour although some have blue, blue-green or greyish-green eyes. At birth, the cubs are snowy white and may be described as resembling polar bear cubs. The birth colour gradually darkens to a pale cream colour known as blond (another name for white lions is blond lions). The mane and tail tuft remain a paler shade. singa putih tidak albino (tidak berpigmen) tetapi leucistic/leucistik - leucism menggambarkan efek daripada gen tertentu. Mereka memiliki pigmentasi yang terlihat di mata, bantalan kaki dan bibir. Mata mereka biasanya cokelat normal atau warna emas meskipun beberapa memiliki biru, mata biru-hijau atau hujau-keabu. Saat lahir, anaknya yang bersalju putih dan dapat digambarkan sebagai menyerupai anak beruang kutub. Warna lahir secara bertahap menggelap menjadi warna cream pucat dikenal sebagai pirang (nama lain untuk singa putih singa pirang). Surai dan ekor seberkas tetap berwarna pucat.
In the Long Island ocelot Club newsletter 23/2 April 1979, Pat Warren wrote "The Color Genetics of Hybrids" based on her F1 Geoffroy's Cat hybrids and F1 Leopard Cat hybrid. Warren considered the cream coloured "white lions" of Timbavati might be the recessive cream dilute of a red colour familiar to domestic cat breeders. In 2008, it was suggested that some very pale captive lions had a gene analogous to "champagne" in horses.
Although the mutation occurred naturally in the wild and has cropped up several times due to hidden recessive genes, white lions do not have a place in the wild. They lack the tawny camouflage needed for survival - this makes them visible to poachers and to the prey, reducing their effectiveness as predators. It is possible that the former range of lions may have included terrain where a blond colour was advantageous. Modern strains of white lions should be considered "man-made" much as a Persian cat is a man-made cat breed. There has been a recent trend in breeding pure white lions for zoo exhibits and animal acts. To ensure genetic diversity, they are crossed with tawny lions from the same region.
Skin and fur get their colour because the tyrosinase
protein helps skin cells manufacture melanin. A genetic defect in tyrosinase
leads to albinism because melanin cannot be made - either cannot be made at
all, or cannot be made properly. This is "c-locus albinism" and it
also affects the visual pathways, sometimes resulting in crossed eyes because
the nerves from the eyes connect up in an abnormal way. In domestic cats, there
are several albino mutations: Burmese sepia (changes black to brown, orange to
yellow), Siamese colourpoint (colour is restricted to head/legs/tail),
blue-eyed albino and pink-eyed albino. There is also the "Inhibitor"
(Chinchilla) gene that prevents deposition of pigment on the hair shaft, but
allows pigment at the hair tips - this is the mutation found in white Bengal
tigers.
The normal colour of lions varies from sandy-golden
through to tawny-brown with the male's mane being dark brown or black in some
subspecies. Faded spots and rosettes may be visible under some lighting
conditions. According to Roy Robinson, noted feline geneticist, white lions
have either the chinchilla or acromelanism mutation. Some older literature
mistakenly referred to chinchilla as a form of albino. The appearance of blond
and white lions (colloquially called leucism) means that colour variations in
lions are probably more common than originally thought. The high mortality rate
in lion cubs means that those colour variations haven't been observed in the
past. White lions have survived due to human intervention.
Though not as common as white tigers, white lions are
now being found in more and more zoos and may well be the current "must
have" big cat. Their value as attractions may well send them down the same
path as the white Bengal tiger: mass production, inbreeding and indiscriminate
crossing with other subspecies e.g. to produce larger, showier manes for circus
acts. Already they have been bred in bulk with no regard for health and used in
canned hunts. If crossed with stripeless white tigresses, white or blond ligers
would result - something almost certain to happen one day because the huge size
of ligers makes them attractive exhibits.
For those interested in human genetics, albinism and
leucism are found in humans; in one striking case of human leucism, a young
girl of African origin presented with milk white skin, normally pigmented
[brown] eyes and golden hair [personal observation, November 2003]
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Tag Archives: white raven
JULY 9, 2014 · 2:09 AM
Crow curiosities: what causes
white feathers?
At a recent field site in Bellevue,
one of my regular visitors was the most fantastically leucistic crow I had ever
seen. Naturally, I dubbed him or her “ZB” for Zebra Bird. One or
two white feathers is pretty common but this was something far more
spectacular. Something that, to the naive observer, may look like a whole
different species of bird. In response, I thought it might be helpful to
talk about how and why crows have white feathers or other kinds of color
aberrations. First off, let’s put some definitions on the table since
there are a few terms that often get mixed up.
Albinism results from a complete lack of melanin in both
the feathers and all the soft body tissues. This causes red eyes and pink
legs, making it very easy to spot. Albinism is often associated with poor
vision and hyper-activity which quickly removes it from the general population
and why, when it is spotted, it’s usually only in young or captive birds.
Leucism is a complete or partial lack of melanin in the feathers, but not necessarily the soft tissues. It is sometimes referred to as ‘partial albanism’ but if you’re familiar with the definition of albanism (which hopefully you are now!) you know the term ‘partial albinism’ is oxymoronic. Leusistic birds can have one or multiple white feathers, as is the case with my friend in Bellevue, or be completely white but with regularly colored eyes. Their feet and bills may or may not appear pink like that of an albino bird’s. Leucism/leucistic/leucistik adalah kurangnya lengkap atau sebagian dari melanin dalam bulu, tetapi belum tentu di jaringan lunak. Hal ini kadang-kadang disebut sebagai 'albanism parsial' tetapi jika Anda terbiasa dengan definisi albanism , Anda tahu istilah 'albinisme parsial' adalah oxymoronic. burung Leusistic dapat memiliki satu atau beberapa bulu putih, seperti halnya dengan teman saya di Bellevue, atau benar-benar putih tapi dengan mata berwarna teratur. kaki dan bills mereka mungkin atau tidak mungkin muncul merah muda seperti pada burung albino ..
Schizochrosim is a lack of a particular pigment. So a
bird lacking the phaeomelanin (brown) pigment, for example, would appear grey.
Melanism is exceptionally high deposits of melanin that
make the animal appear darker overall.
Carotenism is a change in the amount, distribution or
composition of caroteniod (red, yellow, orange) pigments.
Dilution is, as the name suggests, a muting of colors
across all or part of a bird’s plumage.
How do
these color abnormalities arise? There are a couple of different pathways
including genetics, diet and injury/disease.
Genetics
Albinism
is genetic, specifically, it’s linked to a recessive autosomal gene. If
you’re reading this and thinking “autosomal recesisve…what?” remember that
humans have 23 pairs of chromosomes. Twenty two of them are autosomal and
the last pair are sex chromosomes (you’re either XX or XY, sound
familiar?). Recessive means you need two copies of the gene to express
the trait. What this mutation does is cause an absence of the enzyme
tyrosinase, which is used by the body to create some of the colored pigments.
Because albinism is heritable, it can be bred into an artificial population by
a skilled breeder, which is why you may see things like white tigers and lions
in the entertainment business. Despite their dramatic color variation
from their peers, they are not distinct species-an idea I occasionally see
being perpetuated on social media. Genetics also plays a role in leucism, though it’s often only part of a more
complicated mechanism.
Diet
Diets
low in protein may also contribute to leucism, as the amino acid lysine has
been correlated with increased white feathers. This is supported by the
observation that urban birds (who presumably have a diet lower in meat and
protein) typically have more color aberrations than their rural or forested
peers. Carotenism, on the other hand, is
very strongly influenced by diet, since animals cannot produce this color on
their own. A very familiar example of this is seeing the white young of
flamingos who, in this early stage of life, have not yet had enough time to
begin producing mass quantities of their pink pigments.
Age/injury
Lastly, age and injury may also
contribute to feathers which fail to correctly pigment though this is poorly
understood. Somatic genetic mutation (i.e mutations that occur after
conception) are associated with increased age, and indeed, older crows are more
often seen with white feathers. Avian Pox is known to play a role in
carotenism though not much is understood about this.
*Update*
a previous version of this post contained an error stating that humans
have 24 pairs of chromosomes. This has since been
updated.
Lit cited
Guay, P.J., Potvin, D.A., and Robinson,
R.W. 2012. Abberations in plumage coloration in birds. Australian Field
Ornithology 29 23-30.
