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73-556: The Banker horse is a breed of semi-feral or feral horse ( Equus ferus caballus ) living on barrier islands in North Carolina 's Outer Banks . It is small, hardy, and has a docile temperament, and is genetically related to the Carolina Marsh Tacky of South Carolina and Florida Cracker Horse breeds through their shared Colonial Spanish horse and Iberian horse descent. The current population of wild Banker horses

146-492: A mare . A related hybrid, the hinny , is a cross between a stallion and a jenny (female donkey). Most other hybrids involve the zebra (see Zebroid ). With rare exceptions, most equine hybrids are sterile and cannot reproduce. A notable exception is hybrid crosses between horses and Equus ferus przewalskii , commonly known as Przewalski's horse . Zygosity Most eukaryotes have two matching sets of chromosomes ; that is, they are diploid . Diploid organisms have

219-457: A skeletal muscle developmental deficit. In population genetics , the concept of heterozygosity is commonly extended to refer to the population as a whole, i.e., the fraction of individuals in a population that are heterozygous for a particular locus. It can also refer to the fraction of loci within an individual that are heterozygous. In an admixed population , whose members derive ancestry from two or more separate sources, its heterozygosity

292-601: A bloated appearance, a consequence of water retention caused by the body's effort to maintain osmotic balance . The National Park Service (NPS) is concerned about the impact of Bankers on the environmental health of North Carolina's barrier islands. Initially, the NPS believed that the introduced Banker horses would completely consume the Spartina alterniflora grasses and the maritime forests, as both were thought to be essential to their survival. Research in 1987 provided information on

365-448: A breed registry. An early example of people who practiced selective horse breeding were the Bedouin , who had a reputation for careful breeding practices, keeping extensive pedigrees of their Arabian horses and placing great value upon pure bloodlines. Though these pedigrees were originally transmitted by an oral tradition , written pedigrees of Arabian horses can be found that date to

438-927: A broader sense to define landrace animals of a common phenotype located within a limited geographic region, or even feral "breeds" that are naturally selected . Depending on definition, hundreds of "breeds" exist today, developed for many different uses. Horse breeds are loosely divided into three categories based on general temperament: spirited "hot bloods" with speed and endurance; "cold bloods," such as draft horses and some ponies , suitable for slow, heavy work; and " warmbloods ," developed from crosses between hot bloods and cold bloods, often focusing on creating breeds for specific riding purposes, particularly in Europe . Horse breeds are groups of horses with distinctive characteristics that are transmitted consistently to their offspring, such as conformation , color, performance ability, or disposition. These inherited traits are usually

511-738: A common origin. Hemizygous and nullizygous genotypes do not contain enough alleles to allow for comparison of sources, so this classification is irrelevant for them. As discussed above, "zygosity" can be used in the context of a specific genetic locus (example ). The word zygosity may also be used to describe the genetic similarity or dissimilarity of twins. Identical twins are monozygotic , meaning that they develop from one zygote that splits and forms two embryos. Fraternal twins are dizygotic because they develop from two separate oocytes (egg cells) that are fertilized by two separate sperm . Sesquizygotic twins are halfway between monozygotic and dizygotic and are believed to arise after two sperm fertilize

584-407: A given locus, heterozygous describes a genotype consisting of two different alleles at a locus, hemizygous describes a genotype consisting of only a single copy of a particular gene in an otherwise diploid organism, and nullizygous refers to an otherwise-diploid organism in which both copies of the gene are missing. A cell is said to be homozygous for a particular gene when identical alleles of

657-504: A permanent, isolated area for such a large number of Bankers was a challenging task for the Foundation; eight days later the state declared all proposed locations for the herd unsuitable. It ordered the euthanization of the 76 infected horses. Two more horses died in the process—one that was fatally injured during the roundup, and an uninfected foal that slipped into the quarantined herd to be with its mother. Feral horse populations in

730-409: A phenotype. For organisms in which the male is heterogametic, such as humans, almost all X-linked genes are hemizygous in males with normal chromosomes, because they have only one X chromosome and few of the same genes are on the Y chromosome . Transgenic mice generated through exogenous DNA microinjection of an embryo's pronucleus are also considered to be hemizygous, because the introduced allele

803-402: A population: where n {\displaystyle n} is the number of individuals in the population, and a i 1 , a i 2 {\displaystyle a_{i1},a_{i2}} are the alleles of individual i {\displaystyle i} at the target locus. where m {\displaystyle m} is the number of alleles at

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876-488: A registered Thoroughbred be a product of a natural mating, so-called "live cover". A foal born of two Thoroughbred parents, but by means of artificial insemination or embryo transfer , cannot be registered in the Thoroughbred studbook. However, since the advent of DNA testing to verify parentage, most breed registries now allow artificial insemination, embryo transfer, or both. The high value of stallions has helped with

949-399: A result, some Banker horses have been crossed with the Carolina Marsh Tacky , Mustang , Spanish Mustang , and other Colonial Spanish horse breeds . Since 1959, Bankers on Ocracoke Island have been confined to fenced areas of approximately 180 acres (0.73 km; 0.28 sq mi). The areas protect the horses from the traffic of North Carolina Highway 12 , as well as safeguarding

1022-431: A rigorously defined standard phenotype, or for breeds that register animals that conform to an ideal via the process of passing a studbook selection process. Most of the warmblood breeds used in sport horse disciplines have open stud books to varying degrees. While pedigree is considered, outside bloodlines are admitted to the registry if the horses meet the set standard for the registry. These registries usually require

1095-552: A route that brought them within 20 miles (32 km) of the Outer Banks. Hidden shoals claimed many victims, and earned this region the name of " Graveyard of the Atlantic ". At least eight shipwrecks discovered in the area are of Spanish origin, dating between 1528 and 1564. These ships sank close enough to land for the horses to have made the shores. Alternatively, during hazardous weather, ships may have taken refuge close to shore, where

1168-518: A selection process involving judging of an individual animal's quality, performance, and conformation before registration is finalized. A few "registries," particularly some color breed registries, are very open and will allow membership of all horses that meet limited criteria, such as coat color and species, regardless of pedigree or conformation. Breed registries also differ as to their acceptance or rejection of breeding technology. For example, all Jockey Club Thoroughbred registries require that

1241-501: A single oocyte which subsequently splits into two morula . Zygosity is an important factor in human medicine. If one copy of an essential gene is mutated, the (heterozygous) carrier is usually healthy. However, more than 1,000 human genes appear to require both copies, that is, a single copy is insufficient for health. This is called haploinsufficiency . For instance, a single copy of the Kmt5b gene leads to haploinsufficiency and results in

1314-414: A substantial ecological impact in native upland and riparian plant communities. The study recommended a longer-term environmental impact assessment (EIA) of the response of soil, vegetation, and wildlife to free-roaming-horse exclusion in order to better understand the magnitude of these effects. However, the study's authors also noted that magnitude of horse effects will likely vary substantially across

1387-426: Is a limiting resource for Bankers, as the islands are surrounded by salt water and have no freshwater springs or permanent ponds. The horses are dependent on ephemeral pools of rainwater and moisture in the vegetation they consume. Bankers will dig shallow holes, ranging from 2.5 to 4 feet (0.76 to 1.22 m) in depth, to reach fresh groundwater. Occasionally, they may resort to drinking seawater. This gives them

1460-435: Is broad, and the facial profile tends to be straight or slightly convex. In terms of conformation , the chest is typically deep and narrow, and the back is short, with a sloped croup and low-set tail. Legs have an oval-shaped cannon bone , a trait considered indicative of "strong bone", or soundness. Calluses known as chestnuts are small, on some so tiny that they are barely detectable. Most Bankers have no chestnuts on

1533-411: Is called a heterozygote specifically for the allele in question, and therefore, heterozygosity refers to a specific genotype. Heterozygous genotypes are represented by an uppercase letter (representing the dominant/wild-type allele) and a lowercase letter (representing the recessive/mutant allele), as in "Rr" or "Ss". Alternatively, a heterozygote for gene "R" is assumed to be "Rr". The uppercase letter

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1606-406: Is called a heterozygote advantage . A chromosome in a diploid organism is hemizygous when only one copy is present. The cell or organism is called a hemizygote . Hemizygosity is also observed when one copy of a gene is deleted, or, in the heterogametic sex , when a gene is located on a sex chromosome. Hemizygosity is not the same as haploinsufficiency , which describes a mechanism for producing

1679-447: Is estimated to be about 400. Bankers are allowed to remain on the islands due to their historical significance even though they can trample plants and ground-nesting animals and are not considered to be indigenous . They survive by grazing on marsh grasses, which supply them with water as well as food, supplemented by temporary freshwater pools. To prevent overpopulation and inbreeding, and to protect their habitat from being overgrazed,

1752-448: Is expected to be incorporated into only one copy of any locus. A transgenic individual can later be bred to homozygosity and maintained as an inbred line to reduce the need to confirm the genotype of each individual. In cultured mammalian cells, such as the Chinese hamster ovary cell line, a number of genetic loci are present in a functional hemizygous state, due to mutations or deletions in

1825-452: Is homozygous-dominant for a particular trait, its genotype is represented by a doubling of the symbol for that trait, such as "PP". An individual that is homozygous-recessive for a particular trait carries two copies of the allele that codes for the recessive trait . This allele, often called the "recessive allele", is usually represented by the lowercase form of the letter used for the corresponding dominant trait (such as, with reference to

1898-454: Is missing, it is hemizygous , and, if both alleles are missing, it is nullizygous . The DNA sequence of a gene often varies from one individual to another. These gene variants are called alleles . While some genes have only one allele because there is low variation, others have only one allele because deviation from that allele can be harmful or fatal. But most genes have two or more alleles. The frequency of different alleles varies throughout

1971-597: Is proven to be at least as great as the least heterozygous source population and potentially more than the heterozygosity of all the source populations. It reflects the contributions of its multiple ancestral groups. Admixed populations show high levels of genetic variation due to the fusion of source populations with different genetic variants. Typically, the observed ( H o {\displaystyle H_{o}} ) and expected ( H e {\displaystyle H_{e}} ) heterozygosities are compared, defined as follows for diploid individuals in

2044-518: Is that Sir Richard Grenville brought horses to the islands in 1585 during an attempt to establish an English naval base. All five of the expedition's vessels ran aground at Wococon (present-day Ocracoke ). Documents indicate that the ships carried various types of livestock obtained through trade in Hispaniola, including "mares, kyne [cattle], buls, goates, swine [and] sheep." While the smaller vessels were easily refloated, one of Grenville's larger ships,

2117-611: Is thought that the Bankers arrived on the barrier islands during the 16th century. Several hypotheses have been advanced to explain the horses' origins, but none have yet been fully verified. One theory is that ancestors of the Banker swam ashore from wrecked Spanish galleons . Ships returning to Spain from the Americas often took advantage of both the Gulf Stream and continental trade winds , on

2190-460: Is usually written first. If the trait in question is determined by simple (complete) dominance, a heterozygote will express only the trait coded by the dominant allele, and the trait coded by the recessive allele will not be present. In more complex dominance schemes the results of heterozygosity can be more complex. A heterozygous genotype can have a higher relative fitness than either the homozygous-dominant or homozygous-recessive genotype – this

2263-777: The Clydesdale and the Shire developed out of a need to perform demanding farm work and pull heavy wagons. Ponies of all breeds originally developed mainly from the need for a working animal that could fulfill specific local draft and transportation needs while surviving in harsh environments. However, by the 20th century, many pony breeds had Arabian and other blood added to make a more refined pony suitable for riding. Other horse breeds developed specifically for light agricultural work, heavy and light carriage and road work, various equestrian disciplines, or simply as pets. Horses have been selectively bred since their domestication . However,

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2336-610: The Currituck Banks were deliberately culled by hunters in the late 1930s. As a consequence of development in Corolla and Sandbridge during the 1980s, the remaining horses in the northern Outer Banks came into contact with humans more frequently. This proved to be dangerous and sometimes fatal for the horses. By 1989, eleven Bankers had been killed by cars on the newly constructed Highway 12, and several others in Sandbridge. That same year,

2409-542: The Santee River in South Carolina ) failed, forcing the colonists to move, possibly to North Carolina. Vázquez de Ayllón and about 450 of the original 600 colonists subsequently died as a result of desertion, disease, and an early frost. Lacking effective leadership, the new settlement lasted for only two months; the survivors abandoned the colony and fled to Hispaniola , leaving their horses behind. A similar theory

2482-539: The Tiger , was nearly destroyed. Scholars believe that as the crew attempted to lighten the ship, they either unloaded the horses or forced them overboard, letting them swim to shore. In a letter to Sir Francis Walsingham that same year, Grenville suggested that livestock survived on the island after the grounding of his ships. About 400 Bankers inhabit the long, narrow barrier islands of North Carolina's Outer Banks. These islands are offshore sediment deposits separated from

2555-556: The 14th century. In the same period of the early Renaissance , the Carthusian monks of southern Spain bred horses and kept meticulous pedigrees of the best bloodstock; the lineage survives to this day in the Andalusian horse . One of the earliest formal registries was General Stud Book for Thoroughbreds, which began in 1791 and traced back to the Arabian stallions imported to England from

2628-717: The Banker horses. In the 19th and 20th centuries, they were considered an important economic commodity, and regular roundups were held on the islands, called pony pennings . The Bankers were auctioned off to buyers from the mainland. In the 1920s, over 5,000 Banker horses ran wild on the Outer Banks of North Carolina . Today, only two herds remain in the wild: The Corollas and the Shacklefords , with an estimated population of about 400 horses. There are less than 100 Banker horses still remaining on Ocracoke, and many Banker horses face issues with low genetic diversity and inbreeding . As

2701-546: The Corolla Wild Horse Fund, a nonprofit organization, was created to protect the horses from human interference. As a result of its efforts, the remainder of the herd was moved to a more remote part of Currituck Banks, where they were fenced into 1,800 acres (7.28 km; 2.81 sq mi) of combined federal and privately donated land between Corolla and the Virginia /North Carolina line. Corolla commissioners declared

2774-481: The Middle East that became the foundation stallions for the breed. Some breed registries have a closed stud book , where registration is based on pedigree, and no outside animals can gain admittance. For example, a registered Thoroughbred or Arabian must have two registered parents of the same breed. Other breeds have a partially closed stud book, but still allow certain infusions from other breeds. For example,

2847-534: The National Park Service and another qualified nonprofit entity (currently the Foundation for Shackleford Horses). The herd is limited to 120–130 horses. Population management is achieved through adoption and by administering the contraceptive vaccine Porcine zona pellucida (PZP) to individual mares via dart. The island's horse population is monitored by freeze branding numbers onto each animal's left hindquarter. The identification of individuals allows

2920-527: The National Park Service to ensure correct gender ratios and to select which mares to inject with PZP. Since 2000, adoptions of Bankers from Shackleford have been managed by the Foundation for Shackleford Horses. As of 2007, 56 horses had found new homes, 10 resided with another herd on Cedar Island , and two had been moved to the Ocracoke herd. On November 12, 1996, the Shackleford horses were rounded up by

2993-490: The North Carolina Department of Agriculture's Veterinary Division and tested for equine infectious anemia (EIA). EIA is a potentially lethal disease, a lentivirus transmitted by bodily fluids and insects. Seventy-six of the 184 captured horses tested positive. Those that tested negative were allowed to remain on the island and those with the disease were transported to a temporary quarantine facility. Finding

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3066-463: The Sanctuary until the 1940s. It is unclear whether the Bankers swam over from nearby Shackleford or were left by residents who had used the islands to graze livestock. They are owned and managed by the state of North Carolina and regarded as a cultural resource. No management action was taken until the late 1980s and early 1990s, when after years of flourishing population, the island's carrying capacity

3139-591: The United States Lifesaving Service used horses for beach watches and rescues. In addition to carrying park rangers on patrols, the horses hauled equipment to and from shipwreck sites. During World War II, the Coast Guard used them for patrols. In the 1980s, Bankers were used for beach duty at Cape Hatteras National Seashore . In 1955, ten horses were taken from the Ocracoke herd as a project for Mounted Boy Scout Troop 290 . After taming and branding

3212-463: The United States, sometime based on state law and sometimes based on antitrust laws. Horses can crossbreed with other equine species to produce hybrids . These hybrid types are not breeds, but they resemble breeds in that crosses between certain horse breeds and other equine species produce characteristic offspring. The most common hybrid is the mule , a cross between a "jack" (male donkey) and

3285-404: The acceptance of these techniques because they allow a stallion to breed more mares with each "collection" and greatly reduce the risk of injury during mating. Cloning of horses is highly controversial, and at the present time most mainstream breed registries will not accept cloned horses, though several cloned horses and mules have been produced. Such restrictions have led to legal challenges in

3358-497: The breed also indicates Spanish ancestry. A 2011 DNA study of the Banker horse found that it had very low heterozygosity and low mean number of alleles (29), similarly to the Florida Cracker Horse population, which was also shown to have a heterozygosity deficit. The study also showed evidence of DNA similarity of the Banker horse, Carolina Marsh Tacky , and Florida Cracker Horse populations to Iberian breeds . Of

3431-425: The concept of purebred bloodstock and a controlled, written breed registry only became of significant importance in modern times. Today, the standards for defining and registration of different breeds vary. Sometimes, purebred horses are called "Thoroughbreds", which is incorrect; " Thoroughbred " is a specific breed of horse, while a "purebred" is a horse (or any other animal) with a defined pedigree recognized by

3504-417: The example above, "p" for the recessive allele producing white flowers in pea plants). The genotype of an organism that is homozygous-recessive for a particular trait is represented by a doubling of the appropriate letter, such as "pp". A diploid organism is heterozygous at a gene locus when its cells contain two different alleles (one wild-type allele and one mutant allele) of a gene. The cell or organism

3577-466: The female parent. Zygosity is a description of whether those two alleles have identical or different DNA sequences. In some cases the term "zygosity" is used in the context of a single chromosome. The words homozygous , heterozygous , and hemizygous are used to describe the genotype of a diploid organism at a single locus on the DNA. Homozygous describes a genotype consisting of two identical alleles at

3650-441: The gene are present on both homologous chromosomes . An individual that is homozygous-dominant for a particular trait carries two copies of the allele that codes for the dominant trait . This allele, often called the "dominant allele", is normally represented by the uppercase form of the letter used for the corresponding recessive trait (such as "P" for the dominant allele producing purple flowers in pea plants). When an organism

3723-582: The genotype is said to be autozygous . This is also known as being "identical by descent", or IBD. When the two alleles come from different sources (at least to the extent that the descent can be traced), the genotype is called allozygous . This is known as being "identical by state", or IBS. Because the alleles of autozygous genotypes come from the same source, they are always homozygous, but allozygous genotypes may be homozygous too. Heterozygous genotypes are often, but not necessarily, allozygous because different alleles may have arisen by mutation some time after

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3796-431: The hind legs. The coat can be any color , but is most often brown , bay , dun , or chestnut . Bankers have long-strided gaits , and many are able to pace and amble . They are easy keepers , and many tend to be hardy, friendly, and docile. Several of the Bankers' characteristics indicate that they share ancestry with other Colonial Spanish horse breeds. The presence of the genetic marker "Q-ac" suggests that

3869-495: The horses are managed by the National Park Service , the state of North Carolina, and several private organizations. The horses are monitored for diseases, such as equine infectious anemia , an outbreak of which was discovered and subsequently eliminated on Shackleford in 1996. They are safeguarded from traffic on North Carolina Highway 12 . Island populations are limited by adoptions and by birth control. Bankers taken from

3942-418: The horses may have been turned loose. However, the presence of horses on Spanish treasure ships has not been confirmed—cargo space was primarily intended for transporting riches such as gold and silver. Another conjecture is that the breed is descended from the 89 horses brought to the islands in 1526 by Spanish explorer Lucas Vázquez de Ayllón . His attempted colonization of San Miguel de Gualdape (near

4015-573: The horses share common ancestry with two other breeds of Spanish descent , the Pryor Mountain Mustang and Paso Fino . These breeds diverged from one another 400 years ago. The breed shares skeletal traits of other Colonial Spanish horses: the wings of the atlas are lobed, rather than semicircular; and they are short-backed, with some individuals possessing five instead of six lumbar vertebrae . No changes in function result from these spinal differences. The convex facial profile common to

4088-556: The horses' hooves . Banker horses - an introduced species - pose a threat to native ground-nesting animals, such as sea turtles and shorebirds . Feral horses interrupt nesting activities and can crush the young. A 2019 study, citing earlier studies from 2014 and 2017, also found that free-roaming Banker horses also appear to cause some environmental issues by directly affecting other wild species. This included Banker horses potentially limiting these native species ' access to water sources, and that not managing Banker horses increased

4161-436: The horses' diet that suggested otherwise. Half of their diet consisted of Spartina , while only 4% of their nutrients came from the maritime forest. The study concluded that sufficient nutrients were replenished with each ocean tide to prevent a decline in vegetative growth from overgrazing . A 2004 study declared that the greatest impact on plant life was not from grazing, but from the damage plants sustained when trampled by

4234-401: The horses, the scouts trained them for public service activities. The Bankers were ridden in parades and used as mounts during programs to spray mosquito-ridden salt marshes. Notes Bibliography Horse breed A horse breed is a selectively bred population of domesticated horses , often with pedigrees recorded in a breed registry . However, the term is sometimes used in

4307-517: The island from overgrazing. The NPS, the authority managing the Ocracoke herd, supplements the horses' diet with additional hay and grain. In 2006, as a precaution against inbreeding, two fillies from the Shackleford herd were transported to Ocracoke. Public Law 105-229, commonly referred to as the Shackleford Banks Wild Horses Protection Act, states that the Bankers on Shackleford Island are to be jointly managed by

4380-453: The landscape, because horse use intensity and frequency is variable. The ecological effects of free-roaming horses were recommended to be considered in restoration and nature conservation plans for native species . The study noted that some restoration and conservation goals may not be achievable in areas that free-roaming horses occupy, and should therefore not be attempted, because resources would be wasted. The study's final recommendation

4453-839: The mainland by a body of water such as an estuary or sound. The islands can be up to 30 miles (48 km) from the shore; most are less than one mile (1.6 km) wide. Vegetation is sparse and consists mainly of coarse grasses and a few stunted trees. Each island in the chain is separated from the next by a tidal inlet . The Bankers' small stature can be attributed, in part, to limited nutrients in their diet. They graze mostly on Spartina grasses but will feed on other plants such as bulrush ( Typha latifolia ), sea oats , and even poison ivy . Horses living closer to human habitation, such as those on Currituck Banks , have sometimes grazed on residential lawns and landscaping. Domesticated Bankers raised on manufactured horse feed from an early age tend to exhibit slightly larger frames. Fresh water

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4526-541: The modern Appaloosa must have at least one Appaloosa parent, but may also have a Quarter Horse , Thoroughbred, or Arabian parent, so long as the offspring exhibits appropriate color characteristics. The Quarter Horse normally requires both parents to be registered Quarter Horses, but allows "Appendix" registration of horses with one Thoroughbred parent, and the horse may earn its way to full registration by completing certain performance requirements. Open stud books exist for horse breeds that either have not yet developed

4599-453: The other alleles. A nullizygous organism carries two mutant alleles for the same gene. The mutant alleles are both complete loss-of-function or 'null' alleles, so homozygous null and nullizygous are synonymous. The mutant cell or organism is called a nullizygote . Zygosity may also refer to the origin(s) of the alleles in a genotype. When the two alleles at a locus originate from a common ancestor by way of nonrandom mating ( inbreeding ),

4672-420: The population. Some genes may have alleles with equal distributions. Often, the different variations in the genes do not affect the normal functioning of the organism at all. For some genes, one allele may be common, and another allele may be rare. Sometimes, one allele is a disease -causing variation while another allele is healthy. In diploid organisms, one allele is inherited from the male parent and one from

4745-540: The result of a combination of natural crosses and artificial selection methods aimed at producing horses for specific tasks. Certain breeds are known for certain talents. For example, Standardbreds are known for their speed in harness racing . Some breeds have been developed through centuries of crossings with other breeds, while others, such as the Morgan horse , originated from a single sire from which all current breed members descend. More than 300 horse breeds exist in

4818-589: The risk of soil erosion in both riparian and upland plant communities. This was found to decrease ecosystem productivity and function at some sites, and that unrestricted free-roaming horses may, over time, cause stream channel incision and a drop in the water table in riparian areas, particularly if the banks were made unstable by a loss of deep-rooted plant species. The study also found that soil compaction from unrestricted free-roaming-horse use likely limits herbaceous vegetation , because soil compaction can restrict water infiltration and root growth, thereby having

4891-444: The same loci on each of their two sets of homologous chromosomes except that the sequences at these loci may differ between the two chromosomes in a matching pair and that a few chromosomes may be mismatched as part of a chromosomal sex-determination system . If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele

4964-605: The site a horse sanctuary. The population is now managed by adopting out yearlings , both fillies and gelded colts. Conflicts over the preservation of the horses continued into 2012. In 2013, legislation was introduced to help preserve the herd on Currituck. A herd lives on the Rachel Carson component of the North Carolina National Estuarine Research Reserve, a series of five small islands and several salt marshes. There were no horses at

5037-720: The three, the Banker horse was shown to most closely genetically resemble the original Colonial Spanish horse . The Foundation for Shackleford Horses has set up a studbook for establishing the Banker horse as its own horse breed ; as such, it is registered as a critically endangered breed with the American Livestock Breeds Conservancy . Some Banker horses have also been accepted into the Mustang breed registry. Since they are free-roaming, Bankers are often referred to as "wild" horses ; however, because they descend from domesticated ancestors, they are feral horses . It

5110-582: The wild and trained have been used for trail riding , driving , and occasionally for mounted patrols. In June 2010, the Banker horse ("Colonial Spanish Mustang ") was made the official state horse of North Carolina . The typical Banker horse is relatively small, standing between 13.0 and 14.3  hands (52 and 59 inches, 132 and 150 cm) high at the withers and weighing 800 to 1,000 pounds (360 to 450 kg). Other sources list them as taller, standing between 14.0 and 15.2  hands (56 and 62 inches, 142 and 157 cm) high. The forehead

5183-512: The world today. Modern horse breeds developed in response to a need for "form to function", the necessity to develop certain physical characteristics to perform a certain type of work. Thus, powerful but refined breeds such as the Andalusian or the Lusitano developed in the Iberian Peninsula as riding horses that also had a great aptitude for dressage , while heavy draft horses such as

5256-406: Was exceeded. Malnourishment caused by overcrowding resulted in the deaths of several horses; the reserve's staff instituted a birth control program to restrict the herd to about 40 animals. Adopted Bankers are often used for pleasure riding and driving . As they have a calm disposition, they are used as children's mounts. The breed has also been used in several mounted patrols. Before 1915,

5329-451: Was more management of free-roaming Banker horse populations to reduce their negative impact. As the Bankers are seen as a part of North Carolina's coastal heritage, they have been allowed to remain on the barrier islands. To cope with the expanding population, prevent inbreeding and attempt to minimize environmental damage, several organizations partner in managing the herds. North Carolina 's early economic development depended heavily on

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