fuck

fuck

Sunday, 12 January 2014

A second gene pool for the British primitive horse

UPDATE: I fear that the concept of a "British primitive horse" is outdated and not well-supported by evidence. See here

The Exmoor pony is the only remaining pure member of what I like to call the British primitive horse, a native type feral horses that once probably was present on a large part of Great Britain whose historic records date back at least to the 850s AD and that evidently forms the ancestral base of all native British landraces (see here).[1] I still have not figured out how the Exmoor-colour (dark brown without dun) fits the puzzle of what the European wild horse actually looks like (this question is more complex than “breed A vs B” like it is approached by some people), but nevertheless the Exmoor/British primitive horse is a very precious breed and its nature should be preserved. Why? Because that population is the oldest feral horse population that still exists – although the majority of the Exmoor horses lives a domestic life today, they still have their instincts for surviving in the wild even among predators and necessary physical adaptions. And of course, beside their feral ancestry and their ecologic capacities, their phenotype is very primitive as well: small, stocky body, strong legs, large thick head, short frizzy mane and bushy tail; whether or not their lack of dun fits the European wild horse.
Unfortunately, the feral population at Exmoor went through several bottlenecks during the late 19th and early 20th century, but the most severe one was during the Second World War. The numbers dropped down to 50, only 7 of them being stallions (of which one was a crossbred with a thoroughbred). [1] As a result, the genetic diversity of the breed is not very large and the breed tends to be prone to getting horse mange, at least on the mainland.[2] With 800 Exmoor ponies worldwide, the breed is not very numerous as well.

Therefore I came up with an idea how to get more quantity and genetic diversity into the remnant stock of the British primitive horse by some kind of breeding-back or effigy breeding. The basic idea is to collect Exmoor-like horses from numerous less-derived British landraces and to purge out the domestic influence brought in by derived horses from the mainland by selecting them on phenotype and hardiness. Interestingly, there is something similar for the seriously inbred Sorraia, where mustangs (predominantly Kiger) displaying an identical phenotype are bred into the population to gain more genetic diversity. I don’t propagate that the new British primitive horse breed should be crossed into the Exmoor population right from the beginning, but if it turns out to be as stable and as original as the Exmoor, merging the two populations together in the future could in my opinion be considered.

Suitable landraces

When the British primitive ponies where increasingly used for agricultural purposes instead of left free for being hunted, they were crossed and selected for certain purposes. Particularly horses from the Iberian peninsular played a role in this, as you can see in breeds like the Connemara. Many of the so-called mountain and moorland ponies that have a native British ancestry luckily have very wide selection criteria, leading to a great variability that allowed the persistence of original features within them. Human migrations spread the Exmoor-type horses outside Great Britain; on Iceland, they constituted the base of the Icelandic pony (obviously many horses contributed to that breed); it is also the ancestral type of the Faroe pony. They even left a track in Scandinavian horses. Genetic studies showed that British and Scandinavian horses have genetic similarities that endorse their common ancestry, forming a “north pony group”.[2] In the south, the Exmoor evidently influenced some Iberian breeds, such as the Pottoka,[3] maybe also others. I am not sure if the inclusion of such Iberian breeds in such a breeding program would be wise because they might be less cold-adapted (unless they regularly live on high latitudes).

Dartmoor Pony

The Dartmoor Pony ranges free in large numbers in the Dartmoor National Park. It was, just like the Exmoor, another remnant population of the BPH before constant releasing of derived breeds into the moor brought in a lot of domestic features, many Dartmoor ponies do not look primitive anymore, they are actually a rampant cross population. However, there still are some very Exmoor-like individuals in the breed, and they live under the same circumstances as the free-ranging Exmoors.

New Forest Pony



The New forest Pony has a similar history as the Dartmoor, but the Exmoor-like animals are more common and more “complete”.

Fell Pony



The Fell Pony is a descendant of the extinct Galloway Pony, which also resembled the Exmoor closely. It has a black (for black in such a program, read on) or dark brown colour, and some have a useful body conformation.

Shetland Pony


The Shetland is the smallest and stockiest breed in this selection, which is good because the light frame of some of the other breeds needs to be compensated. Some Shetlands have a good colour.

Welsh Pony

The Welsh is more gracile and more derived than the other breeds here, but some of them still have a good colour and a short mane.

Highland Pony


The Highland Pony is very variable, it has individuals with a small stocky body and the right colour.

Icelandic Pony


The Icelandic Pony is a breed displaying many different colours, including bay, dark brown and black (there are even black dun individuals, but those are not interesting for a program for the British primitive horse). Some Icelandic ponies are optically almost identical to the Exmoor.

Faroe Pony


The Faroe was taken to the islands between the 7th and 9th century, and some of them also display a phenotype meeting all criteria desired. Counting only about 50 individuals in number, they are extremely rare.

Gotland Pony



The Gotland has several lineages, including small and stocky ones that are virtually identical to the Exmoor on the looks.

Dales Pony


The Dale Pony has some very nicely coloured dark brown and black individuals with the right body conformation.

Kerry Bog Pony


This Irish breed has, as you see, some very useful individuals as well.


To get a genetic diversity as high as possible, as many suited breeds as available should be used. I, personally, would include all those breeds. This increases the unwanted traits of course, but that could be counteracted by keeping a careful eye on the founding individuals and the herds they are from. Especially the stallions should be of high quality. Another question is how large the founding population should be to create a large and diverse gene pool. If between five and ten individuals of each of these 11 breeds are chosen, 55 between 110 individuals would form the base of the population. If that is feasible would depend on the financial capacity of the program of course, but I’m just thinking about a theoretical guideline here. A breeding book should be set up right from the beginning to not repeat the mistakes the Heck brothers did with their cattle and horses we do not know today what cross animals these are actually based on.

The breeding criteria to consolidate the original phenotypic features of the British primitive horse in a kind of “Exmoor Pony 2.0” should be:
  • Size between 115-135 cm
  • Stocky body with strong legs
  • Large, thick head with strong jaws
  • Short, frizzy mane
  • Coat colour either bay or brown with prominent pangare/mealy mouth or black
  • Ability to thrive on natural forage and sustain cold temperatures, surviving winters without supplementary feeding if they are present at an appropriate density
  • Shy and cautious behaviour
I included the last point because it is known that horses living semi-feral do not easily loose their tameness what can provoke situations dangerous for horses and people.[2] I am confident that all of those 11 breeds I chose here are hardy and robust, but to further select on this trait cannot be a mistake. I think that this new breed does not have to be totally phenotypically identical to the Exmoor, f.e. some variation regarding the skull shape could be permitted if it increases its primitiveness (as I explained in the previous post, the Exmoor has domestic skull features such as enlarged eyes and a shortened snout). Now let me explain why I would permit black colour in this population if it is obviously not present in the modern Exmoor. Actually, black horses seemingly always were present within the Exmoor/British primitive horse; they were reported as recently as the 19th century, but the bottleneck events purged them out of the modern population.[1] Black colour is not only a colour of the original Exmoor, but also one of the two basic wild type colours in horses (among bay, which probably was more common based on genetic evidence) [4,5] and it is very useful for camouflage. So this colour should be reintroduced in any case if such a project to re-unite the original features of the British primitive horse is ever to become put into practise.

I already contacted Mr. David Brewer, Chairman of the Exmoor Pony Society, regarding my idea, and he told me that my idea was already looked into and that they keep a careful watch on the blood lines of the Exmoor with the aid of genetic testing, I guess to avoid too much inbreeding.

Literature

[1] Baker, Sue, 2008: Exmoor Ponies: Survival of the Fittest – A natural history.
[2] Bunzel-Drüke, Finck, Kämmer, Luick, Reisinger, Riecken, Riedl, Scharf & Zimball: Wilde Weiden: Praxisleitfaden für Ganzjahresbeweidung in Naturschutz und Landschaftsentwicklung. Arbeitsgemeinschaft Biologischer Umweltschutz
[3] Royo et al.: The Origins of Iberian horses Assessed via Mitochondrial DNA. 2005.
[4] Ludwig et al.: Coat colour variation at the beginning of horse domestication. 2009
[5] Pruvost et al.: Genotypes of predomstic horses match phenotypes painted in paleolithic works of cave art. 2011



17 comments:

  1. Love to read your posts. Just wondered if you have read the recent report by the
    Exmoor national park into the origins of the pony. It has proved a bit controversial because the evidence does not support the notion that the Exmoor is descended from an originally wild population. Or that they were formerly of the present coloration.
    Great post this one with some nice pictures. Just wondered why you have not covered the Dartmoor pony as it is equally as strong a contender as some of the other breeds listed. Not only that there is some reason to suspect that the first imported domesticated ponies were released onto dartmoor in the bronze age. If your interested I could share with you some of my thoughts.

    ReplyDelete
    Replies
    1. Oops, just re read my text. Was meant to have asked why you hadnt covered the Dartmoor pony in previous posts, as obviously you have here. I blame my phone for that mistake.

      Delete
  2. Hi, first of all, thanks for the nice words! I have covered the Dartmoor Pony previously, but did not focus much on them because they basically are, like I said in the text, a rampant cross population but with some nice individuals. I went to Dartmoor two days after I visited Exmoor two years ago, and I saw a lot of them.
    No, I haven't heard of that report yet. Do you have a link or something?

    ReplyDelete
  3. Daniel, i think you really should read more about color genetics. I think you make the same fault as you blame the people selecting for dun. When you read the paper of Pruvost really carefully, you will read that since there is no definite genetic test for dun yet, since the genes causing the dun-phenotype are not yet known, dun can not be excluded as a primitive color.
    Most ecologists read the paper and seem to remember only the colors "bay" and "black" and forget about the "dun"-part. In the research there was sought apart from whitening genes (overo, sabino-1, Lp-roan) and dilutions (cream, silver) for the "basic" color genes E (extension of black) and A (restriction of black) that are responsible for the basic DOMESTIC colors of bay (in its variations) and black (in its variations). Simply put, it was clear since there was no "e" found on the E-locus, meaning black pigment is completely supressed, that there were no "ee" horses in the predomestication samples, which means the color "chestnut" or red-with-no-expression of black, was not between them, that combination was only discovered in a copper-age sample. Now the E-gene means that eumalanin or black pigment is expressed, while the A-gene means that the black pigment is restricted to certain areas on the body (outline = tail, manes, lower legs, head). The combination of E and A or a (EEAA (bay), EEAa (bay), EEaa(black)) define if a horse is bay or black. So far no problem. BUT : the duntype of color is (as all other modificating genes) is acting ON TOP of E and A. Duntype is single dominant and typed as "D" = dun, and "d" = non-dun. This means that a bay horse with the dun-modification is coded (in case of the predomestic horse where there is no "e" present) as "EEAA (or Aa)+ DD (or Dd)" and a bay horse without the dun-markings and lighter coloring is coded as "EEAA(or Aa)+dd". Same for black : EEaaDD or EEaaDd = black-dun (grulla) or EEaadd (simple black).
    The research of Pruvost et Al could not and does not give (literally) conclusion for the dun-modification.
    Apart from that on the Agouti-locus there are two other allels defined besides A(plain-agouti) and a (non-agouti), those are A+ (or wildtype-agouti, wildbay) and At (or sealbrown / sooty-agouti). This last gene shows a darker faze of agouti from the spine down, leaving the underline (armpits, loins, innerthighs and muzzle) more clear in color than the almost black topline. There is a recent genetic test for this gene but is was not used in the research of Pruvost et Al.
    This At-modification has a lot of resemblance with the "pangare"-modification in bay, which is found in exmoor and other horses (for instance "Ardennais", an ancient draft-type from the french part of belgium which resembles the exmoor a lot), and it is even thought of as being the same modificator.
    Allmost all, if not all, mammals show a clear apearance of black pigment (eumelanin) combined with red pigment (pheomelanin), therefor, to me the color "black" showing no evidence of red pigment (as in friesians, fell- and dale-poneys, merens ....) is allready an abrasion of the original genome.
    In the case of the black predomestication horses, which are pointed as being EEaa, could very well be "EEAtAt" or "EEAta" (apart from the dun-modification) since before the test for "At" this was seen as "a"......do you follow ?!

    I think the bay-pangare color of the exmoor (and others) could be very related to the expression of dun (as in konik, sorraia, hucul and others). Remember the pictures I send you in PM, maybe it is high time to take a closer look at the distribution of pigment within the hair, so we need a scientist that can do this..... (samping different old breeds and compare them)

    ReplyDelete
    Replies
    1. Hi Peter, thank you for your explanations but I think you misunderstood me on this post. I am aware of what you describe here, and in fact I did not exclude dun as a wild type colour feature, not at all. I actually think that the evidence that European wild horses is way better than that they lacked dun; if that's not clear in this post, my other post should be very clear on that. I do not make the same mistake as Henri Kerkdijk-Otten and kin and draw purpose-lead conclusions from that. I think it is more likely that European wild horses were, just like other extant wild equines, dun-coloured. I was just talking about the Exmoor phenotype as that of a primitive formerly feral horse type that is IMO worth to be preserved.

      Delete
  4. www.exmoor-nationalpark.gov.uk/environment/wildlife-and-ponies/exmoor-ponies

    There is a link on the above page to the new exmoor pony study. I think you will enjoy it.
    I own three dartmoors and so I am probably just sticking up for them. There are 3 types of pony on Dartmoor. The pedigree dartmoor, bred from the original population but mixed with arab and hakney blood. Then there is the heritage pony, unregistered but resembling the original population. Then there is the hill pony, a mongrel of mixed breeding, largely composed of dartmoor, exmoor, shetland, welsh mountain, goonhilly, bodmin, cob pony blood. The farmers have selected for a broad range of colours in an attempt to meet the demands of the market. These ponies probably represent one of the most genetically diverse populations in the uk. All my ponies are bay, two with very primitive meally mouths and in summer a slight dapple effect. I know of two dun dartmoor hill ponies with vestigial stripes. If there is any way I can assist you further then let me know. All the ponies on dartmoor are under threat. I personally think that this ancient landscape should become a kind of giant zone for free roaming herds of tarpan like ponies and rare breeds of sheep and cattle. Check out my facebook page on my attempts at turning my ponies into pack animals. Page is called Dartmoor Pony and Pack,
    If you can find it.

    ReplyDelete
    Replies
    1. Hi, thanks for the article, I'll read through it when I find the time. I had a look at your Facebook page, you have very nice Dartmoor Ponies! They would be perfect for such a project that I proposed here.

      Delete
  5. OK Daniel,
    but regarding the conformation, apart from color, wouldn't it be better to "re-flesh" an ancient horse sceleton, like you did allready with the aurochs.... and what about the measurements of the Danish skeleton, f.i, the canonbones and the ribs look rathter thin instead of "sturdy", and what about restructing the outlay of ancient skulls ?

    ReplyDelete
    Replies
    1. This comment has been removed by the author.

      Delete
    2. Lol, that's all upcoming! I did such reconstructions already, just haven't had the time yet to present and describe them here. The Danish skeleton is fully reconstructed on my desktop and ready to be published. Hope to do that tomorrow.
      The real problem is that for the European wild horse there is far less material to work on… at least on the web. I'd be pleased if anyone knows of some more useful photos.

      Delete
  6. Hello there, nice to read your post once again.
    Just a small information regarding this sentence in your article - I am not sure if the inclusion of such Iberian breeds in such a breeding program would be wise because they might be less cold-adapted (unless they regularly live on high latitudes) - I must say that all Iberian breeds are suited for cold temperatures and specially the ones from the north: Garrano, Galego, Astur and Potoka because the climate in Iberian Peninsula is not all the same and the average temperatures in the southern coastal areas are very different from those in the mountain regions and specially above Tagus river. Most of this regions have precipitations over 1000 mm a year, in Galicia and northern Portugal one may find many regions over 2000 mm a year (what is among the highest levels of precipitation in all Europe), with all those regions having snowy winters with many days with temperatures bellow zero reaching -10C quite often and with a very stormy and irregular weather, actually the climate in the Cornwall and Devon regions in SW Britain is quite similar.
    Just as an example the Sorraias raised outside Portugal, in Germany in US or in Canada have no problems with local winter time and Sorraia breed is originally from the Tagus low valley region in the south of Portugal quite warmer place than those breeds from the mountains up north.
    Meaning that I can guaranty that any of those above mentioned Iberian breeds would feel perfectly at home in Exmoor region and in most of Europe.
    Best regards
    J. Ferro

    ReplyDelete
    Replies
    1. Thanks for the precise information! Actually I was expecting that, just like the Iberian primitive cattle breeds do perfectly virtually all over europe, and Sorraia do well in Germany, but I was simply (too) cautious. Apart from that, some people might have objections against using Iberian breeds to reconstruct a second gene pool for the British primitive horse, especially because the Introgression of the Exmoor is proven only for the Pottoka and, IIRC, the Asturcon.

      Delete
  7. also applyable on other species as equus (allthough equus ferus ferus as such is now extinct) :
    http://www.ncbi.nlm.nih.gov/pubmed/22066758

    ReplyDelete
  8. Hi, good article. I leave a link to an article website, it is about horses of the north of Iberian. Hope you like it. A greeting and a hug. http://zaragozasalvaje.blogspot.com/2012/07/el-caballo-cantabro-pirenaico.html

    ReplyDelete
  9. One of the oldest breeds of horse in Spain is in danger, the last losinos horse or pony Burgos, the last population of the day was a race called "Spanish Jaca" direct descendant or Thieldón Celdón horse that used in wars against the Roman Empire Celtiberians, these horses may actually end up being burgers. It will lose a piece of living history of Spain.
    http://zaragozasalvaje.blogspot.com.es/2014/01/caballos-losinos-al-matadero.html

    ReplyDelete
  10. Hi, I find your blog very interesting, do you know the name of the pony in the middle picture of the above photos of dartmoor ponies, or remember where the photo was taken? I have never seen a dartmoor that looked that much like an exmoor.

    ReplyDelete
    Replies
    1. It's from this page: http://www.urlaubmitpferden.com/de/dartmoor-pony.html

      Delete