Thursday, 19 October 2017

Wild horse series Pt.II: The Konik, Exmoor and Sorraia myths

In my 2017 wild horse summary I had a look at what the evidence suggests regarding the life appearance, extinction and population genetics of European wild horses. There are some open questions, but also some things that we can say with certainty. One of those things is that European wild horses are as extinct as the aurochs. Nevertheless, there are three horse breeds that are often referred to either as surviving wild horses or near-wild horses, having a special status among European horses in being particularly close to the original wild form. Those three breeds are the Polish Konik, the English Exmoor pony and the Portuguese Sorraia, and each one of those has its own proposed background story that is supposed to link them closely to European wild horses. Those stories, however, are only purported and believed by advocates of those breeds, people involved in various projects, and are spread exclusively in non-scientific text books, public relations articles, or on signs in zoos while nothing of them is replicated in scientific literature, and none of those breeds are considered zoologically special among domestic horses. Advocates of the breeds blame a “conservative scientific mainstream” that is biased against the idea that the European wild horse might still be extant in some form, while the truth is that the background stories for the purported special status of the Konik, Exmoor or Sorraia are largely based on wishful interpretations, Chinese whispers and fabrications, actually making those stories myths that do not withstand objective examination.
Here I want to present and subsequently dismantle those myths. When not relying exclusively on sources that repeat the same stories over and over, but actually provide a deeper background knowledge, backed up by more evidence than usually delivered, it becomes rather obvious that the usually purported background stories for those breeds are not tenable. Yet those stories are pretty persistent and widespread, and I hope this post might become a little contribution to clear things up. 

The Konik myth: The Polish game park at Zamosc was the place were Europe’s wild horses survived longest. In the year 1806, these wild horses were donated to local farmers of the Bilgoraj region and incorporated to their farm horse stock. In the 1920s, the Polish agriculturist Tadeusz Vetulani started a breeding-back project using wild horse-like individuals from the Bilgoraj region and bred them selectively for a wild horse-like nature, eliminating the domestic influence their genome experienced in the hundred years before. He called the result “Konik”.
The truth behind it: Whether or not the supposed wild horses at Zamosc were truly wild and not feral, it is unlikely that they left a noticeable trace in the local farm horses. This claim is based on a notion by Julius Brincken in a book from 1826, but this book is full of errors, misinterpretations and fabrications, so it is not a reliable source. Furthermore, the Zamoski family was at war with the local farmers due to social unrests in the 1780s and 1790s, so it is unlikely that they would have provided them with generous gifts in the form of livestock. And even if they did, it is unlikely that the farmers tolerated a strong wild influence in their horses as it would have been a throwback in their productivity and suitableness for agricultural work, as wild horse hybrids used to show intractable behaviour [2]. And even if they incorporated wild horses, and perhaps only mares, into their stock, not much would have been left after 100 years. So it is very unlikely that the horses of those particular rural regions of Poland had a notable wild horse influence in the 20th century [1,2].
In Poland, there was/is a landrace called Panje horses. Those horses were very robust, of a small and stocky body and varying in colour between black dun, black, sorrel and bay. In an 1921 article, Panje horses were considered as possible wild horse descendants (which is to be refuted for the reasons stated above) by the researchers Gabrowski and Schuch. This drew the attention of Polish agriculuturist Tadeusz Vetulani to the Panje horse as “wild horse relict”, he tried to back up this suspicion with cranial measurements (that have been questioned [1]), and coined the name “Konik”, which successively replaced the name Panje horse. Private and public studs were created in order to preserve and spread the landrace. In 1927, Vetulani started an experiment that is often considered a “breeding-back” experiment, but was actually more of a dedomestication attempt, using Konik/Panje horses that he considered wild horse-like. But Vetulani’s herd was only one of many Konik lineages back then, and the Second World War created a lot of confusion, as many Koniks were moved all over Poland and Germany during and after the war. After the war, the stud at Popielno was the most important Konik breeding site. They performed two separate ways of breeding: one to continue Vetulani’s way of few human interference, and one of traditional indoor breeding and commercial sales. Popielno was one of many breeding sites, and when other countries started to become interested in this breed, they purchased from any stud available [2].
Thus, neither was Vetulani’s experiement an experiment of selective breeding, nor was it the ancestral stock of the modern Konik population but merely one of many lineages [2]. He did not create the breed, but merely coined the modern name of the breed. The fact that 10-5% of the modern Konik still show a black or sorrel colour or white streaks on the forehead (respectively) reveal the mixed origin of this landrace [2], and there is no compelling, not even plausible, evidence that their ancestral stock was strongly influenced by wild horses [1,2].
The Heck horse, which is often presented as a “recreated Tarpan” in Germany and also other countries, is in a sense a washy Konik – it was created by the Heck brothers in the 1930s and 1940s by crossing Icelandic horses, Gotland ponies and Dülmen ponies with a Przewalski stallion. Later on, Koniks were used massively as breeding stallions on Heck horses, so that they are heavily influenced by that breed, hence the large optic resemblance [8]. The same was the case in the Dülmen pony, which is why the three breeds sometimes are regarded as the Konik group [8]. The Liebenthaler horse can also be regarded as a member of this group.

The Exmoor Pony myth: The Exmoor Pony is a remnant population of a wild horse type or at least a feral type of very original western European horses that once ranged on the entire British island. Several other populations of this primitive British horse type have been intermixed with derived horse breeds, creating the modern British pony breeds such as the Welsh Pony, New Forest Pony, Dartmoor Pony and others. The Exmoor Pony however is the only population that retains a stable, wild horse-like appearance with a brown colour, countershading + white muzzle and a sturdy body. The similarity to other northern ponies such as the Gotland or Faroe Pony, and especially some primitive Iberian breeds such as the Garrano and Pottoka, endorse the hypothesis of a north-western European wild horse/primitive horse type that once was found in this region and is most authentically represented in the form of the Exmoor pony.
The truth behind it: At first, this scenario sounded convincing to me. But what is most important to note first is that equines disappeared from the archaezoological record of the British isle at the end of the Mesolithic until domestic horses were introduced by the Celts [3,4,5]. Therefore, the Exmoor pony cannot be a remnant wild horse population or wild horses with domestic introgression, they have to be of domestic origin. But this alone does not rule out that they are the last representative of a homogeneous, feral and primitive horse population that once ranged across the entire British isle. One argument is their homogeneously small body, comparably short mane, the brown colour with countershading plus white muzzle. However, careful examination suggests that the population at the Exmoor never was homogeneous after all[4]. There are no helpful references prior to the 18th century on the colour variants found in the Exmoor population. Between 1805 and 1809, 81 Exmoor ponies were sold from the moor. Their colour was documented and included black, grey, bay, dun, chestnut and one piebald individual. There is no evidence that purposefully “non-pure” Exmoor ponies were caught in this case. Two illustrations in the Illustrated London News from 1835 clearly show horses with a long mane, their colours are probably implemented to be brown with a white blaze and sock, grey and a black one [4]. A notion by Worthley Axe in the year 1906 is even more revealing: “… the majority of the so-called Exmoors are simply mongrels” [4]. The Acland herd, which made a considerable contribution to the modern Exmoor population, also included a number of greys and blacks in 1900. There is a record that suggests that black Exmoor ponies were selected out because they lacked the expression of the white muzzle, indicating that artificial selection started back then. Furthermore, the Exmoor pony population went through several bottlenecks, the most severe in course of the Second World War. A stud book for the breed was set up in 1921, at first black and grey individuals were tolerated but selected out later. It is thus far more in line with the evidence that artificial selection and genetic bottlenecks created the homogeneous external appearance we see in the modern Exmoor pony, and there is no evidence that it was homogeneous prior to 1906. Most likely the Exmoor pony that is always brown in colour with countershading, a white muzzle and no white markings is an invention of the 20th century [2]. It would therefore also be more parsimonious to assume that other British pony landraces like the Welsh pony, Dartmoor pony or New Forest pony never were homogeneous either. Furthermore, the use of British ponies including the Exmoor pony on Iberian breeds like the Pottoka in the 20th century is well-documented[2], which is at least partially responsible for the optical resemblance. Thus there is no empiric basis for a once feral, primitive free-ranging horse type that looked like the Exmoor and ranged across Great Britain or even whole western Europe.
Also, which is important to note, Exmoor ponies most often display a colour variant that is called seal brown, At. This is an allele that has not been identified in wild horses yet, in contrast to the two wildtype alleles bay A+ and black a [6,7], and therefore most likely is a domestic colour. The black individuals, which have been actively purged from the population, however, would have displayed a wildtype colour variant [6,7].

The Sorraia myth: The Portuguese agriculturist Ruy d’Andrade spotted a herd of strongly striped, free-ranging horses in a remote region in Portugal. He considered them to be a remnant population of the zebro, a strongly striped Iberian wild horse type. He was unable to find them again, but collected a number of farm horses from that region that he considered to be closest to those horses, and started to breed them. This is the modern Sorraia horse, by some even communicated to be identical to the zebro and thus a wild horse.
The truth behind it: The claim that the Sorraia is a surviving Iberian wild horse is flawed by the story itself – d’Andrade did not catch any wild horses and started breeding them, but merely collected farm horses he considered to be reminiscent of the horses he spotted. He collected four local stallions and seven mares, and a Criollo stallion was added later on. Therefore, the Sorraia is a descendant of domestic farm horses. But is it possible that is particularly strongly influenced by an optically identical Iberian type of strongly striped wild horses, the zebro? First of all, there are not any references suggesting a survival of wild horses on Iberia into the beginning of the 20th century. C.H. Smith reports free-ranging horses of black dun and bay dun colour with wild markings that ranged from the Camargue, parts of Spain to the Ardennes, Great Britain and Scandinavia (see here), but also describes them as “sturdy mountain-forest ponies”, and it is not clear if those are wild or feral horses anyway. Regarding the actual zebro, it seems that this population of equines vanished in the 16th century [8] and many authors tend to consider them feral donkeys instead of horses. Indeed a genetic test of the skeleton of the supposedly last zebro turned out to be a donkey [9]. The strongly striped ashy grey colour of wildtype coloured donkeys is very reminiscent of the black dun colour scheme in horses.
The allegedly strong stripe pattern of the Sorraia is often purported as its trademark and an indicator of particular primitiveness that links it to the zebro. However, stripes are part of the bay dun and black dun colour scheme and found in many horse breeds. Therefore, it does not give the Sorraia any special status (see a very strongly striped Hucule here, for example).
Ferus-type wild horses are usually assumed to have been comparably small and sturdy in build. The Sorraia, however, is comparably large (140-150cm at the withers) and lanky. As there is no comprehensive archaezoological record of predomestic wild horse skeletons that has been osteometrically examined (only some single fragmentary specimen) it can neither be proven nor ruled out that Iberian wild horses were larger and more gracile in build than other Eurasian wild horse types, but it would be necessary to have evidence at hand for making such a claim.
More importantly, genetic information has revealed the Sorraia as a domestic horse [10].

I am going to come back to genetic studies more extensively in the next part of the wild horse series 2017. A closer look at the respective history of those three breeds that are often supposed to be wild horse relicts, near-wild horses or recreated wild horses alone is sufficient to show that there is actually nothing of substance that suggests that these three breeds deserve a special status among robust landraces of European domestic horses. But this of course provokes the question which horse breeds are best suited to be used as a substitute for the European wild horse in ecologic restoration. Thus, the upcoming post is on this question as much as on the domestication of the horse in general.

Similar but older posts: 

Literature

[1] Cis van Vuure: On the origin of the Polish Konik and its relation to Dutch nature management. 2014.
[2] Tadeusz Jezierski, Zbigniew Jaworski: Das Polnische Konik. 2008.
[3] Baker, Sue, 2008: Exmoor Ponies: Survival of the Fittest – A natural history.
Baker
[4] Peter Green, 2013: The free-living ponies within the Exmoor National Park: their status, welfare and future. A report to the Exmoor moorland landscape partnership. 
[5] Bunzel-Drüke, Finck, Kämmer, Luick, Reisinger, Riecken, Riedl, Scharf & Zimball: „Wilde Weiden: Praxisleitfaden für Ganzjahresbeweidung in Naturschutz und Landschaftsentwicklung“. 2010
[6] Pruvost et al.: Genotypes of predomestic horses match phenotypes painted in paleolithic works of cave art. 2011
[8] Bunzel-Drüke, Finck, Kämmer, Luick, Reisinger, Riecken, Riedl, Scharf & Zimball: „Wilde Weiden: Praxisleitfaden für Ganzjahresbeweidung in Naturschutz und Landschaftsentwicklung“. 2010
[9] L. Orlando et al.: Revising the recent evolutionary history of Equids using ancient DNA. 2009.
[10]  Lira et al.: Ancient DNA reveals traces of Iberian Neolithic and Bronze Age lineages in modern Iberian horses. 2009



13 comments:

  1. Hi Daniel,
    At this point in time, research is still ongoing with regard to the Konik horse. As a scientist myself and equine anatomist, the Konik does not dissect the same as a domesticate horse. The anatomic research suggests unprecedented comparative findings between Konik horses and domesticates. The gene coding for such variations have not yet been identified.

    If such findings are not found in the domesticate, then where does the comparative begin? Hence we have been dissecting Equidae from Donkeys, Przewalskis, Koniks, a Grant's Zebra and of course domesticate breeds (18 breeds).

    However, as we are about to submit our findings on one such variation, I suggest you attend the seminar at Utrecht University in Holland 15th November (equinestudies.nl). Several of the phenotypic findings will be discussed including the soon to be published current research.
    Regards,
    Sharon May-Davis
    PS. A number of the skeletons involved in the research that we as a team have dissected will be on display for public perusal.

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    1. Hi, when comparing the phenotypes, it should perhaps be remembered that the Konik has had introgression from the Przewalski's horse several times after the second world war, particularly in Germany. In some herds/individuals it more apparent than in others. http://www.visualphotos.com/photo/1x9399921/Konik_Horse_V84-1346091.jpg

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  2. Could you please provide a reference for the crossbreeding to the Przewalski that you mentioned. As the Konik was established in Poland in the early part of last century and suffered a genetic bottleneck post WWII, breeding to Przewalskis would also have been difficult as this breed was close to extinct also.

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    1. One of them would be "Der polnische Konik", given in the reference list in the post - basically all horses bred by Lutz Heck had influence from a Przewalski stallion, so all Koniks that descent from the horses of Heck have introgression from Przewalski's horses. Furthermore, there subsequent new incrossings of Przewalskis into German Heck horses after the war (some of them even have an upright mane), and since breeders in Germany often do not distinguish between pure Koniks and Heck horses, it has become a rather intransparent situation in Germany. The reference for that is N.5 in the literature list.

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    2. Interesting food for thought - thank you Daniel.

      I have not been dissecting German Koniks, nor was I aware of this breeding line. However, as I am in Germany twice a year, I will put this discussion to my German counterparts who I converse with. Thank you

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    3. As part of Heck's stock was based in Poland, and some of them were sold back to Polish farmers, his horses might or very likely did influence also the Polish population as far as I know.

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  3. It's off topic...is it known what would happen if a donkey stallion would be crossed to a Przewalski mare ? Would an offspring have 63 or 64 chromosomes (Przewalski has 66) ? Would this be same or different from other mules, regarding fertility ?

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  4. More in general, recent article:
    'Coat colour adaptation of post-glacial horses to increasing forest vegetation'
    Edson Sandoval-Castellanos, Saskia Wutke, Constantino Gonzalez-Salazar and Arne Ludwig.
    https://www.nature.com/articles/s41559-017-0358-5.

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  5. Coat colour adaptation of post-glacial horses to increasing forest vegetation
    Nature Ecology & Evolution (2017)
    doi:10.1038/s41559-017-0358-5

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    1. Thanks, I'm going to cover that paper in an extra post. Thanks for addressing me to that paper.

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  6. The donkey/przewalski cross fertility question is very interesting. Maybe it could be easily answered by a geneticist without the need for a physical attempt. The coat colour adaptation study was very interesting, great that such an obscure topic but relevant to all of us who read this blog would be investigated.

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  7. The donkey/przewalski cross fertility question is very interesting. Maybe it could be easily answered by a geneticist without the need for a physical attempt. The coat colour adaptation study was very interesting, great that such an obscure topic but relevant to all of us who read this blog would be investigated.

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  8. Do you know what the genetics are for falling vs standing manes? I am designing a hypothetical project to create an effigy breed of Equus (ferus) lambei, the Yukon horse, by crossing takhis with cold-adapted domestic breeds like Fjord, Icelandic, and especially Yakut ponies. We know that Yukon horses were bay duns with primitive markings, like takhis, and that they were roughly twelve hands with a very stocky build. Those are all traits I understand and which can be bred for. However, it is also known that Yukon horses had blonde, falling manes. At first I thought that they might have had the silver dapple dilution factor, but I now think that unlikely. I think they were probably blonde in the manner of Fjord horses, which do not have the silver dapple gene. I have been observing pictures of takhis and found that their manes also have a fjord-like colour pattern, with lighter hairs on the sides and black hairs in the middle. The pattern is less pronounced and less noticeable due to the shorter, more rigid conformation of the mane, but the mane is certainly not completely black. Anyway, anything you could tell me about the genetics associated with mane conformation would be very much appreciated. Thank you.

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