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Marandaise{origins of the dark brown egg {

Discussion in 'General breed discussions & FAQ' started by Resolution, Dec 22, 2009.

  1. Resolution

    Resolution Chillin' With My Peeps

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    The origins of domestic species is a fascinating field of interest for some.
    For example, where did the domestic cattle originate? What were some of the overlaying factors that led to its domestication in the first place? Why were wild cattle more successful as domestic species than say, oryx, which were also kept as captive animals by the ancients?

    How were specific traits, phenotypic and/or morphological/behavioral, selected for, early on in the domestication of the species?
    How many generations of close inbreeding were necessary before the prerequisite 'fixing' -of phenotypic expression- that would characterize the domesticated version- distinguish it from its wild progenitor?

    In short, just where and when in the course of history did the domestic cattle (Domestic Species) emerge from its wild ancestor ( Wild Species) ?
    When could domestic cattle be distinguished from wild cattle as a matter of fact and not intuition?
    This integral step was necessary before cattle would become the foundation of a successful culture utilizing cattle/meat/milk/hide/etc. as its currency; providing an entire society with with staples needed for survival. Cattle culture is one of the founding developmental phases of humanity. So, it's more than just a precursory interest in cattle that leads some to investigate the origins of the domestic cattle. Its a curiosity about our own common history as human beings that leads many towards that field of interest.

    Wild Species held in captivity by human beings where self-selection of mates is greatly reduced and bred in a specific direction or direction is called selective-breeding.
    This is a prerequisite step in the domestication of a wild species. Once the Wild Species has been transformed by human beings into a largely human-crafted phenomenon, it has skipped the rails, so to speak. Under the supervision and maintenance of human kind, these altered lineages are moving away from the evolutionary potential of a naturally selected creature to become a Domestic Species.

    Moving to a slightly different topic:

    Learning about the origins of a specific Breed within that Domestic Species tends to draw an interest for a larger number of people, possibly because it draws on cultural inceptions and ingenuity. Where archaeologists are interested in the previous field of interest, many a historian will stake their tent at this subsequent step in the development of a Domestic Species.
    Returning to cattle once again, in the migration of a culture characterized by its dependency on domestic cattle, we often witness evidence of the emergence of novel regional strains that differ from the original Domestic Species-often exponentially over time. These new strains may well share a common progenitor at their origin. In other words, these novel strains of the Domestic Species are generally descended of the same Domestic Ancestor. However, for any number of reasons, consequent of specific factors, some known to us and some still a mystery, Unique Regional Strains with a tendency to produce certain mutations, dark red colouration for example, would become breeds.

    Over a period of many hundreds or thousands of years, a Domestic Species becomes of vital importance to a culture of people. Consequently, that culture is enabled to grow and evolve thanks to the consistence resource of protein and fats, leather and so on, provided by that domestic livestock species. This successful culture eventually migrates from its original homelands into a new region, carrying their treasured Domestic Species of livestock with them. The primitive phase of this culture's Domestic Species are, without exception, genetically homogeneous. That is to say that the flocks or herds of this primitive phase in the domestication process are, by necessity, comprised of very closely related individuals. Nevertheless, in relocating to new regions some distance away from their place of origination, these homogeneous populations tend to experience more significant genetic bottlenecks than those closer to the homeland. Perhaps the greatest reason for this is that when a flock or herd member perishes or escapes from captivity, it is not easily replaced.
    This further reduces the gene pool.


    So, how is a true Breed of a Domestic Species created? That's a two part question.

    1. A wild species was held in captivity for unknown number of generations. Captive born progeny were select bred from, within a very small pool of genetic founders. In other words very close relatives were bred together- as a rule and- for generation after generation after generation, until a goodly percentage of unique, naturally selected genes, which would otherwise distinguish a specific evolutionary phenomenon -that is, a Wild Species- these unique genes are basically melted off- through selective breeding between close relatives. This selective breeding- the removing of layer after layer of onion skin inherited via natural selection-- it generates a genetically homogenized domestic species.
    Domestic species, by and large, are not fit to survive in the natural habitats of their Wild ancestors. They may however survive and even thrive in environments alien to their ancestors. Human beings tend to create environments that are ideal for their Domestic Species. They may also introduce their primitive domestic species to islands and other environments where predators and competitors are either very rare, or absent altogether. In these situations, the Domestic Species generally reverts to a stage closer to its wild progenitors, as the animals return to a feral existence. In these situations the animals self-perpetuate, selecting their own mates and rearing their own offspring.

    2. Cultures responsible for the original domestication of a given Wild Species, may or may not have refined the Domestic Species into respective strains.That is, they may have taken the Wild Species through the first primitive phases of domestication and no further. Through migration and fusion with other cultures;
    Through the creation of new cultures, Unique Regional Strains emerge from the original Domestic Species. This generally requires another re assortment of genes from two or more lines of even more thoroughly homogenized founders. Again, returning to domestic cattle, three respective, very closely bred strains of Domestic Cattle are merged into a new herd. While the first few generations of intercrossing between strains dissolves genetic bottlenecks, resulting in a less genetically homogeneous Domestic Cattle herd, close inbreeding within that herd - for example, only one bull is used for two or three generations, only to be replaced by his sons, then grandsons and so on and son for decade after decade- the herd is once more comprised of extremely closely related individuals. This herd is theoretically very different in appearance and perhaps behavior from any of the parental populations. No new genes are introduced and progeny from this one herd are traded and sold over a wide region. There are no other cattle in this region. This population becomes its own breed through time and isolation, genetic drifts and selective breeding. Ecological factors may also be involved, which we will discuss later.

    Domestic breeds emerged from ancient cultural diaspora and subsequent isolation.

    Something that is very important to remember here, is that the vast majority of Domestic Breeds are not directly descended of a Wild Species.
    Domestic Breeds are direct descendants of a Domestic Species. The Domestic Species is derived from at least one ancestral Wild Species.
    This is very important to keep in mind as we move ahead into the actual crux of the discussion of the origins of the dark brown egg.

    Ok, so- at this point- we've discussed the difference between a Wild species and a Domestic species. We've also covered some integral steps or phases in development- in the creation and delineation of Unique Regional Strains, which result in the eventual creation of Breeds. Now let's touch briefly on the significance of Cultural Heritage and Modern Utility Breeds respectively.

    The generation of specific Cultural Heritage Breeds within a Domestic Species will hold more focus for the cultural anthropologist, for the special brand of historian most interested in their own or a specific ethnic culture. Shetland Highlander Cattle, for example, are an important Cultural Heritage Breed.
    Perhaps the most interesting thing about Highland Cattle is the story of their origination, where they came from and what culture is responsible for their development. I'm personally more interested in their adaptation to the Shetland Isles themselves. Their ancient ancestors were in the primitive phase of domestication- originating in Anatolia. They were carried by Phoenicians to the Celts who carried them to Scotland. Some wild European Auroch bulls contributed their genes along the way. Eventually they became their own Unique Regional Strain and eventually one of the most significant cattle Breeds.
    Sustainable Agriculturists generally work with Heritage Breeds because they are more suitable for natural environments. They tend to require less management and have less of a negative impact on the land they are maintained on. They also have a story that is helpful in marketing their yield. Besides that, they tend to be more tasteful- more genuine and homey on the table than commercial breeds.

    Likewise, the generation of specific Modern or Utility Breeds within a domestic species are the sole focus of many others. In fact, the field of discussion on the origins and significance of modern breeds comprises the majority of information on domestic species in general. I don't have to go into any length about the significance or development of these
    major components of the global economy.

    The dispersal, ownership and exhibition of Heirloom Strains of a given breed is another subject altogether.
    Broadus line cattle are an heirloom strain of the Highland Cattle Heritage Breed. They are more valued by some than others but have a history unique to their lineage, and as such, hold intrinsic value and provide a specific nexus of desirable traits that breed true to type.

    The Freedom Ranger broiler is a Commerical Utility Breed and one could argue that it is and was an heirloom at its inception...

    I'm writing this to preface a larger discussion on the origins of the Dark Brown Egg.
    It's fundamental to gain comprehension on how certain desirable attributes of a wild species-that is, certain characteristics or traits of a wild species, end up being selected for-over a long and protracted history, to eventually become the characteristic trait of a given domestic species . Case in point, the dark brown egg.
    Where did it originate? Why does it matter? How can it be selected for?

    To recap:
    1.Wild Species: Red Junglefowl Gallus gallus
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    Naturally selected species inhabits native habitat.

    2.Domestic Species descended of wild Red Junglefowl Progenitor Species: Domestic Fowl Gallus domesticus
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    * This preliminary stage/phase in domestication produces a subrace of the Wild Species that is difficult to distinguish from its wild progenitor and yet very different morphologically and behaviorally from its wild progenitor.

    3.
    a.Cultural Heritage Breed and Land Race
    descended of Domestic Fowl Progenitor Species
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    ** this second phase in the domestication process produces distinctive strains breeds that are generally associated with a specific region of ethnic culture.
    They are more genetically homogeneous than their Domestic Species progenitor and midway between fully Domestic Breed and Wild Species ancestor.
    The birds in this photograph are from a closed flock living on a tiny atoll near Guam. The island has not been inhabited for over two hundred years. No new genetics have come in. These birds, nevertheless, represent the Chamorros peoples, and as such are referred to as Chamorros Fighting Games


    b.and Modern Utility Breed
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    *** the third phase (modern utility) of the domestication process produces distinctive strains that no longer resemble their Domestic Species progenitor and are purely manmade abstractions designed for utility. The modern utility breed has no evolutionary potential to speak of and is basically a dead end so far as self-perpetuation is concerned. While some modern utility breeds can set and hatch their own eggs, the likelihood of their doing so without human beings is exceedingly low. Predators would be the first factor in preventing their natural self-perpetuation. They tend to attract predators via vocal and behavioral traits selected for in the domestication process. They also tend to make poor parents as a rule. .

    4. Heirloom Strain of a given Domestic Breed :
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    **** the fourth phase of domestication is a bit of a grey area. Any lineage that has been carefully conserved and select bred is an heirloom. It does not necessarily need to be a rare or cultural heritage breed to be an heirloom. If there are more than eight generations of a line with no new blood added Or are the product of a master poultier ( Nancy Utterback or Bill Braden, for example) the lineage is an heirloom. Woe be the idiot that purchases this genetic material and plays Dr. Moreau with it. This is where the cavalier, short-sighted mud maker does a disservice to the focal breed and to the discipline of poultry stewardship. Many Heirloom Strains will be lineages carefully bred from excellent stock and may represent a single specific colour type.


    Ok. Now we can discuss the Dark Brown Egg.
     
    Last edited: Dec 27, 2009
  2. Resolution

    Resolution Chillin' With My Peeps

    Our Dark Brown Egg{ Why does it matter?

    What if anything is the significant of the Dark Brown/Dark Red Egg?

    From an academic source”
    The ancestral white egg has been retained by species whose nests are safe from attack by predators, while those that have moved to a more vulnerable nest site are now more likely to lay brown eggs, covered in speckles, just as Wallace hypothesized more than a century ago. Even blue eggs might be cryptic in a subset of nests built in vegetation( or open to the sky on desert islands) It is possible that some species have subsequently turned these ancient adaptations to new functions, for example to signal female quality, to protect eggs from damaging solar radiation, or to add structural strength to shells when calcium is in short supply

    Theoretically speaking, the dark pigments actually act as reinforcement over the surface of the shell. Thus, ship better and remain fresh longer. This was very important before the advent of the refrigerated truck. True chefs will tell you the importance of storing eggs at room temperature for utilization in the kitchen as well. So a dark brown egg has its own special wrapping protecting it from germs and making it a bit harder, tougher to crack. Naturally everyone loves to gaze at these masterpiece orbs as well...
    I think too, there may well be selective advantages for hens in cool wet forested regions of Europe- to produce darker egg shells- ones that better match the substrate –guarding against predation from the never ending litany of egg eating crows-foxes and gulls. Might these eggs also absorb a bit more warmth from a rare sunny day and then hold that heat in a tad bit longer on the cool rainy following it? You know how long it takes for a hen to lay enough eggs to set a clutch. In cold rainy spring...

    ok- so where did this beautiful coloured egg originate- where were the actual pigments inherited from? How can they be improved upon or further enhanced?

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    Just about everyone reading this is already familiar with the fact that:

    1. The Red Junglefowl Gallus gallus is the matriarchal ancestor of all domestic chickens.

    What they may or may not have known is that there are actually two sister species of Red Junglefowl.

    There is the Mainland or Burmese Red Junglefowl Gallus gallus spadiceus

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    and is sisterspecies the Indonesian Red Junglefowl Gallus bankiva.
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    While these two similar forms look very much alike, their molecular biology and respective geographic ranges, indicate that they are not as closely related as their appearance may suggest. Apparently, the Indonesian Red Junglefowl is the more primitive, whilst its sister species, the mainland form, is more recently contrived- that is- it split from Indonesian ancestors and only fairly recently- during the Pleistocene.

    The Mainland Red Junglefowl has at least three geographic races of its own. These are genetically difficult to distinguish from one another, yet occupy an extensive collective range. They are just tiny twigs in the crown stem of the Mainland Red JF. Nevertheless, the large diversity of old Asiatic continental breeds has this composite of geographic races of the one Red Junglefowl form at its foundation. That is to say, the first domesticated fowl of China were not Indonesian game breeds but composites of mainland Red JF strains bred for succulent flesh and eggs.

    Not incidentally, both Red Junglefowl forms produce, and without exception, pale, whitish eggs. The Indonesian produces an egg shell that is a bit more dun coloured - perhaps. Red Junglefowl eggs nevertheless, exhibit no spots, no blotches nor dark russet washes. There is very little if any variability of eggs within a clutch. Indeed, the species is an infamous clutch dumper- that is- young hens will often lay their eggs in a single nest- sometimes their own mothers -even in wild birds. Odd looking eggs would work against that reproductive strategy.

    Getting back to egg pigment origins, the Indonesian Red Junglefowl is younger in age- more contrived as they say to a clade of closely related species; the Ceylon and Grey Junglefowl. Just as the Mainland Red JF split evolutionarily from the Indonesian Red JF branch so too had the Indonesian Red Junglefowl split from its ancestral branch rooted firmly in the phylogenetic locus occupied by the Ceylon/Grey species clade.

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    *Note the relationship between Gallus spadiceus ( Mainland Red JF ) and Gallus bankiva ( Indonesian Red JF )
    ** Note the relationship between Grey Junglefowl Gallus sonnerati and Ceylon Junglefowl Gallus lafayetti .
    Note-Gallus bankiva is slightly more closely related to G. sonnerati and G. lafayetti.

    Whereas there is no variability of egg shell colours within the Red Junglefowl superspecies, the Ceylon and Grey Junglefowl produce highly variable eggs.
    This is more marked in the Ceylon Junglefowl than in the Grey. It should be noted that Ceylon Junglefowl also produce smaller clutches, incubated for shorter periods than other Junglefowl species, including the Grey. In nature, the Ceylon is known to reproduce all the year round. Variability in the eggs of Ceylon Junglefowl are advantageous in terms of nest predation. Being an Island species, and an ecological specialist, the Ceylon Junglefowl's predators are exceedingly familiar with the birds habits and nesting preferences. Nest predators are far more common than obligatory predators and as such, eggs must be difficult to see. Where the birds nest in deep forest the eggs tend to be paler, but where populations of the birds are inhabiting very steep ravines (their preferred environments) there is a greater tendency for the eggs to be darker, with more markings. This additional pigmentation may also be directly linked with a higher intake of specific amino acids procured in these ravines- crustaceans like isopods and copepods, pill bugs and the like; Grey Junglefowl, also produce variable eggs but only produce one or two clutches a year. Their eggs tend to be either more highly freckled or less freckled. They lack the heavy splotches of the Ceylon- and again, in captive Ceylon and even wild birds that inhabit denser more vegetated forest on flatter ground, the splotches of the Ceylon egg tend be difficult to see- or are non-existent. For more complete description on the eggs of both species please read William Beebe's treatise on the Junglefowl. I have read about both Ceylon and Grey Junglefowl producing completely pigmented eggs. The Ceylon clutch being russet and the Grey being ochre.
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    Ceylon Junglefowl prefer very steep ravines to flat or rolling hills to reproduce in. There are localized populations in regions where steep ravines are the rule (versus rolling jungle habitats). In these populations, richly pigmented eggs with dark splotches and freckles are the rule. The background colour of the eggshell of this species is a faint yet decidedly warm ochre or pink.




    Obviously, at some point, the significance of Ceylon Junglefowl alleles will be discussed. For now, there is another very important layer within the domestication of the domestic fowl that needs to be covered before we can discuss genetic introgression from another species.​
     
    Last edited: Dec 28, 2009
  3. ve

    ve Chillin' With My Peeps

    1,870
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    Jan 27, 2009
    Palmetto GA
    Now I will not sleep all night waiting for second part ![​IMG]
     
  4. joletabey

    joletabey SDWD!!!!

    Apr 9, 2009
    western NC
    OK, I am ready for enlightenment.
     
  5. becky3086

    becky3086 Crested Crazy

    Oct 14, 2008
    Thomson, GA
    Very interesting. I will be waiting for the next part as well.
     
  6. kathyinmo

    kathyinmo Nothing In Moderation

    I'm ready .... lay it on me! [​IMG]

    ETA: I'm thinkin' this is gonna be way over my head!
     
    Last edited: Dec 22, 2009
  7. Mahonri

    Mahonri Urban Desert Chicken Enthusiast Premium Member

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    North Phoenix
    My Coop
    I LOVE learning posts like this.

    C'mon Dark Brown?


    Mutation? Artifical Breeding Selection? Both?
     
  8. pinkchick

    pinkchick "Ain't nuttin' like having da' blues"

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    Washington State
    Can we ask questions yet?????????? [​IMG]
     
  9. kathyinmo

    kathyinmo Nothing In Moderation

    Quote:NO, Sshhhh, class is in session. Be quiet and wait for the lecture to finish. [​IMG]
     
  10. drom

    drom Chillin' With My Peeps

    Jun 12, 2008
    California
    Yipee. [​IMG]
     

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