Some questions and answers

This post is a kind of Q&A post with questions that I have been asked quite frequently or that simply might be interesting. Note that the answers to the questions represent my personal opinion or interpretations based on the sources that I have.

How many types of European wild horses do you think there were during the Holocene?

The common anecdote of a “forest tarpan” and a “steppe tarpan” is not based on reliable evidence. Rather, genetics suggest that there was a continuum from the Russian steppes to the Pyrenees, and the Iberian peninsular being a separate gene pool. Whether or not there were any morphological differences between these populations or within the continuum is not examined yet. So there is no hard evidence for different geographical horse types. Geologically, however, the populations changed over time according to newest genetic evidence. During the Pleistocene, dun horses were predominant while during the Holocene, black phenotypes became more dominant, which is probably related to the shift from an open to a forested habitat. 

When did the European wild horse die out?

This cannot be ascertained as multiple scenarios are possible. Either the genuine wild populations died out completely and were later replaced by feral horse populations in historic or prehistoric times, or there was a gradual shift by continuous depletion of the genuine wild population and intermixing with feral horses, so that the last free-ranging horses at the end of the 19^th century were completely feral horses with no wild genes. It is also possible that they were hybrids or, perhaps less likely, still pure wild horses – there is simply not enough data for it.  

Why is there so much less on wild horses on the Breeding-back blog? 

Because there is much less to say. First of all, it is not certain when predomestic horses really died out in Europe, there is not a single articulated Holocene wild horse skeleton or at least a cranium that can be found anywhere, the true life appearance of wild horses as much as the historic sources are dubious and not to forget that the difference between wild horses and domestic horses is not as large as between aurochs and cattle. 

Your opinion on the word “Tarpan”? 

My opinion is that this word should not be used in order to avoid confusion. It was not a vernacular term for the European wild horse as often claimed, but rather a local term in the Russian steppes for the free-ranging horses, whatever these were (it is possible that they were feral domestic horses, caballine wild horses, caballine wild horses mixed with feral horses, Przewalski’s horses or Przewalski’s horses mixed with feral horses). The word “Tarpan” is also connected to the unsupported hypothesis of a “forest tarpan” and a “steppe tarpan” as much as myths such as the alleged origin of the Konik. It would be better to abandon the term overall, regardless its widespread use, and simply refer to predomestic horses in Europe as exactly that or simply European wild horses. 

What do you think about water buffaloes for Europe nature systems? 

I am aware of the ecological benefits of water buffaloes in the reserves where they have been used due to the turbation of small water bodies they make, but I don’t think that water buffaloes would be inevitably necessary in European ecosystems. The subfossil record does not document it unambiguously, also the evidence in Austria is dubious. However, I do think that water buffaloes that are suited to European climate would do no harm. A crossbreed of European domestic buffaloes and Asiatic wild buffaloes might be the best option for this job.  

Did the Heck brothers good work or not?

There is an extensive article on this question. I think we owe the Heck brothers something for inventing the idea of breeding-back. Without their initiative, there probably would be none of the projects or cattle that we have today. But yes, their work was sloppy to a certain degree and could have been done better with the possibilities back then, f.e. they could have done more precise research on the actual morphology of the aurochs, they could have made a herd book and more strict selection criteria. And of course, claiming their heterogeneous breeding result with its only vague resemblance to the aurochs is a revived aurochs was a-zoological. 

Hybridization with living wild bovines for “breeding-back” yes or no? 

I tend to say “no” to this idea. It would make breeding back results species hybrids, what would make the academic and public acceptance for the breeding back results even more difficult. However, a small-scale project crossing wild yaks with breeding back results could be interesting and might also be beneficial for the survival rate of the cattle during winter, as wild yaks are way better adapted to surviving cold winters than domestic cattle. 

Which cattle breed that is currently not used would you like to see being used in breeding-back? 

Quite a lot: Maltese, Chillingham, Corriente, Florida Cracker, Turano-Mongolian breeds, Camargue and others. They would add diversity to the gene pool, and have many beneficial traits; Camargue and Maltese have a very slender morphology, Corriente look very good in general, Chillingham and Turano-mongolian cattle are very hardy and suited to cold climate. 

Will the aurochs ever return in its original form? 

As the full genome of one British aurochs bull from the early Holocene has been completely resolved, it is possible – one way would be to edit the genome of a cattle individual with CRISPR-Cas9 and replace the domestic alleles with aurochs alleles and let a large domestic surrogate mother carry the aurochs calf. It would be interesting to see how far epigenetics and “junk” DNA will influence the development of the individual. I wrote an article on what to do with a living aurochs. 

Which is the best breeding-back project? 

I think there is no fair way just to pick one project or breed. All the current projects have advantages. For example, the Auerrind project has really good quality founder individuals and is experimenting with interesting combinations. The Tauros Programme has quantity, they gained areas and herds rather quickly and now they have to breed for quality individuals. Taurus cattle has both considerable quantity (about 100 individuals in the Lippeaue and 400 in Hortobagy alone) and a lot of high quality individuals that are on the top of what “breeding-back” has achieved so far (Lamarck, Lerida, and other Taurus individuals). It would be most beneficial in my opinion if the three major projects would cooperate, and it seems like this is going to happen some time in some form. One large metapopulation of the best breeding-back cattle available would be an ideal scenario. The resulting cattle could simply be summed up under the umbrella term “breeding-back cattle” or “aurochs-like cattle”. 

Which “breeding-back” herd currently has the best animals? 

In my opinion, definitely the Lippeaue Taurus cattle herd in Soest, Germany. Not because it is the herd that I know best but simply it has a lot of quality animals to offer which have not been surpassed or equalled in other herds yet – Lamarck, Lerida, 42 623, Loxia, Lambretta and many others. In Hortobagy, Hungary, there might be some individuals of a similar quality but I do not know those herds thoroughly enough. 

Which one do you consider the most aurochs-like breed? 

This is a question that is very hard to answer. It also depends on what level you compare the cattle. But, as all factors of a living organism are interconnected, most cattle that have a less-derived anatomy also have less derived behaviour and survival capacity. Actually I think the Iberian fighting bull, Lidia, is one of the least-derived cattle breeds on this world. It is one of the very few cattle breeds that truly has a wild cattle-like morphology despite being small and often having too short legs. Its morphology and behaviour suggests to me that its “domestication syndrome” is not as intense as in many other breeds. There are people who do not consider it aurochs-like because of its exaggerated aggression level, but the tame and docile nature of other breeds is not aurochs-like either. The aurochs was probably in between. A breed that I also consider very aurochs-like, but not in the same way, is Maronesa. It is the only primitive breed that has a well-pronounced inwards curve in the horns and a flawless colour setting with, most importantly, a well-marked sexual dimorphism. This breed is, however, short-legged (bulls) and of small body size. Corriente is also a very aurochs-like breed overall, but small as well. The Maltese ox is remarkable for being large, long-legged and long-snouted but the horns are meagre. After all, all breeds have their pro’s and con’s, but I would say that these four are on the top of those breeds that I am aware of. Lidia, however, sticks out to me for the overall very primitive appearance and morphology. 

Saying that Maronesa or Lidia, for example, are very aurochs-like, would you expect those breeds also to be genetically closer to the aurochs than derived breeds? 

Yes, I think it would show in the genetics to some degree. But I still think that the aurochs is so far removed from all living domestic cattle that the difference might not be that noticeable. It should not be forgotten that there are eight millennia of domestication, a rather dramatic process concerning the genetic structure, are between aurochs and cattle, regardless of local hybridization. 

Is recreating the aurochs by selective breeding possible? 

As I explained in a number of recent posts (for a summary, go here), I do not think it is possible to recreate the aurochs by selective breeding with modern domestic cattle. Domestic cattle are too remote (both in evolutional and organismic matter) from their wild ancestor, the domestication process was probably too intense and domestic cattle are too derived so that a lot of the original gene material of the wildtype was probably lost during this process that is lasting for eight millennia now. 

Can we call breeding-back results “new aurochs”?

I think that we should not call any cattle “new aurochs”. It is true that aurochs of the 21^st century would differ a little bit from those of the 16^th century, just as those of the 16^th century differed slightly from those of the late Pleistocene, but domestic cattle bred for optical resemblance would still be a huge step apart from all geological and geographical variants of the predomestic wild aurochs. Calling domestic cattle a new aurochs just provokes associations with the overly simplistic negligence of the Heck brothers, who indeed thought they had revived the aurochs just by crossing a couple of cattle breeds. It also gives the wrong impression that whenever a wild animal disappears, we can “breed it back” anytime anyway. 

Only a totally dedomesticated strain of aurochs-like cattle would be something that I would call a postdomestic wildtype, just as the aurochs was the predomestic wildtype, but I would not call them aurochs, as it is zoological consensus that “aurochs” refers to the predomestic wildtype of cattle. 

What do you think on the relationship of the quagga and the “Rau quagga”? 

I covered this issue in this post. To me, the Rau zebras are normal plains zebras that have been selected for a reduced stripe pattern while the quagga apparently was more distinct – although this topic is perhaps understudied. Regardless of whether it was a distinct subspecies, a geographical cline or just a colour variant, the Rau Zebras share only a superficial resemblance with the Quagga due to the reduced stripe pattern. While the reduction of stripe pattern in Rau zebras is impressive, it is not completely identical to that of the Quagga, and on a genetic basis, the Rau zebras have nothing to do with the Quagga. In the same way Burchell’s zebras would not suddenly become Grant’s zebras when bred for a more extreme stripe pattern, or Timber wolves would not end up as polar wolves when bred for an exclusively white phenotype. Therefore, I think the Rau zebras should not be called “Rau quaggas” as they are not any more related to the quagga in any sense than other Burchell’s zebras. 

If I would do a breeding project, what would it be like? 

I have so many ideas. For once, I would like to try the combination Maronesa x Chianina/Maltese and supplement it cautiously with few doses of Watussi for horn volume. Or, in order to increase genetic diversity in “breeding-back” start a project working with breeds never used in “breeding-back” before, also including Turano-Mongolian breeds (see this post) or Chillingham cattle and Corriente.. It would also be interesting to breed a herd of the best Lidia individuals which resemble the aurochs to a large extent, and supplying them with breeds that add size (f.e. Chianina, Maltese) and horn volume (Watussi, for example). 

Very tempting to me is the idea to take herd of good “breeding-back” results and select them for wildtype-like behaviour (shyness, low agreeableness, more extreme fight/flight reaction) and to see if the morphology also reverts back to a more wildtype-like condition (this idea would be a reverse experiment the Farm fox experiment and has been introduced in this post). 

Also, it has been an idea of mine to breed an aurochs-like zebu herd (see here). 

Selective breeding with horses for a strong stripe pattern would be to see how far selective breeding can drive the stripe pattern in horses would be interesting as well. 

Apart from “breeding-back” herds, what I would really like is to carry out a project that creates a large and healthy wisent herd that was supplemented by cautious hybridization/introgression from American bison as described in this post. 

If I would want to start a breeding herd now, which where would I take the cattle from? 

I would take some good individuals from the Lippeaue plus perhaps some good and promising Auerrind crosses, and would maybe add one or two individuals from breeds not yet used in breeding back, such as Chillingham or Corriente. This is the composition I would take if I want a larger breeding-back herd. If I’d like to breed on a smaller basis for a line focusing on quality only, I would simply take some good Lippeaue Taurus cattle and try to breed them for maximum quality.

If one extinct species could be reconstructed with genetic methods, which one would be of your preference?

Most resources are concentrating on the woolly mammoth at the moment, and I think this is a good choice – the woolly mammoth is spectacular, popular and important enough to be the first extinct species brought back to life. It would also be my whish that the Tasmanian tiger or moas could be recreated, although this is probably impossible due to the lack of genetic information and suitable surrogate animals. And of course, genetically recreated aurochs would also be very delightful. 

Which one is the most wild horse-like: Konik, Exmoor, Sorraia, Dülmen or others? 

In my opinion, none of them is particularly close to the European wild horse. In the case of the Dülmen pony, it is evident that the modern population is a mix of mostly northern ponies and the Konik, and there is no evidence that the original population from the medieval times were true wild horses. For the other three breeds, genetic tests never unambiguously showed a special status for any of those breeds, and the breed history for both the Konik and the Sorraia shows that it was bred using rural horses, and it also seems that the modern Exmoor pony is an invention of the 20^th century. 

If any of those breeds would indeed descend from one of the last remaining wild horse populations, it would definitely show in the genetics; they would be quite set apart from European domestic horses. Also, their documented breed history evidences otherwise as well. Furthermore, their phenotype does not match up. Most recent genetic evidence suggests that Holocene wild horses were mostly of a black phenotype, while none of those breeds above are of that colour. 

Are zebu and taurine cattle different species? 

I think there is definitely no good reason to classify zebuine cattle and taurine cattle as separate species. Surely they are phenotypically far removed from each other, but that is due to artificial selection. Indian and European aurochs, the “natural” state of both clades, were probably not so far removed from each other. There are some gametic processes that show incipient speciation, but subspecies are always incipient species. It is purely a matter of taxonomy that has no relevance for the actual science, but zebuine and taurine cattle and therefore also European and Indian aurochs should be listed as one species in my opinion. 

Heck cattle is a good or bad “breeding-back” breed? 

Heck cattle of course does not meet the initial goal of phenotypically replicating the aurochs, far from it. However, it is an extremely heterogeneous population. While some herds, especially those in zoos and private farms that experienced little selective breeding, are barely useful for breeding back, there are many herds nowadays that are a pretty good basis to work with. Especially regarding the horns, as many of the better Heck cattle have horns that are very good in terms of dimensions and OK in terms of curvature, thanks to lineages such as the Neandertal herd or Walter Frisch’s former herd in Wörth/Steinberg. Not to forget, Heck cattle always have a very good winter coat and are well-suited to Central European climate, which is useful when crossbreeding with southern breeds. 

Was original Europe one big forest or a grassland savannah? 

I believe that as so often, the truth probably was between both extremes. For once, I think the theory that the natural state without any human interference would be forest in Europe is flawed by the fact that we have many indicator species for open land that were present in Europe’s interglacials long before humans arrived, so Europe could not have been just one big forest. Furthermore, bovines were shown to have been pretty common game in the subfossil record, and I do not believe that forest alone would have provided enough suitable space for such large populations to dwell. However, it seems that palinological evidence shows that Europe was not one big grassland, and the faunal utopia of aurochs, wisent, water buffalo, elks, wild horses, Equus hydruntinus and other large game present all over Europe is not backed up by the subfossil evidence either. For example, the European wild horse was much less common in the Holocene than in the Pleistocene, and the record for water buffaloes is dubious. There is solid evidence for wild ass in parts of Austria, but as far as I know only in Austria. Europe probably was not such a large game paradise as Africa, but neither was it a closed canopy forest. Considering that this continent is very multifaceted geologically and geographically, I think it probably was a mosaic of closed, semi-open and open landscapes.